Sir: I have the honor to submit to you the following report of the operations of the chemical laboratory of the Department:
The operations have been confined to a period of two months; for although commissioned by you to undertake the duties of chemist to the department as early as August 21, 1862, I was, immediately upon my arrival in Washington, detailed by the President upon special service, and not remanded to your department until the close of October. The organization of the laboratory operated for a further delay.

Major Adlum, the introducer of the Catawba grape, who published, at Washington, in 1823, a treatise upon the cultivation of the vine in America, made the following remarks respecting the Catawba grape, in a letter to Nicholas Longworth:  "In bringing this grape into public notice, I have rendered my country a greater service than I could have done had I paid off the national debt.”

From small beginnings the culture of the wine grape has become a source of great national wealth, with abundant promise for the future. The census returns show the number of gallons of wine made in the United States to have been, in 1840, 124,734; in 1850, 221,249; and in 1860, 1,860,008.

Within the last two years the impetus to the wine manufacture has been such that persons familiar with the subject estimate the actual vintage of the past year at 5,000,000 gallons.

Forty years ago Major Adlum, in his preface to the above-mentioned work, calls attention to the grape and to wine-making as a "valuable but too much neglected branch of agriculture;” and, speaking of this neglect, continues:  "It was to prevent this evil (as far as I could be instrumental in preventing it) that I wished to obtain of the President of the United States, a few years ago, a lease of a portion of the public ground of the city for the purpose of forming a vineyard and of cultivating an experimental farm. It was my intention, had I been successful, to procure cuttings of the different species of the native vine to be found in the United States, to ascertain their growth, soil, and produce, and to exhibit to the nation a new source of wealth which had been too long neglected. My application was, however, rejected, and I have been obliged to prosecute the undertaking myself, without assistance and without patronage; and this I have done to the full extent of my limited means. A desire to be useful to my countrymen has animated all my efforts and given a stimulus to all my exertions.” It is an appropriate tribute to the author of these patriotic sentiments that in Washington, where he labored, the work in the laboratory of the Department of Agriculture should have been inaugurated with a chemical examination of the native grapes of our country.

The operations in the laboratory, as well with sorghum as with grape juice, can only be regarded as preliminary to a more extensive investigation of the subject in the next season. These operations were begun after the period of the harvest of the respective crops, and the time was too brief to procure desirable specimens. The correspondence and communications of the new department were in progress of formation, and much labor in various directions had to be performed. Hence, in respect to grapes, specimens of the most important actually grown for wine, such as the Catawba and Concord, were not accessible. Some of the specimens procured were in too small quantity for proper examination, and some were of varieties useless for wine, while ail were in a condition rendering a very rapid analysis imperative. I adopted the plan, in the present investigation, of analyzing all of the specimens received; determining in each case the specific gravity of the filtered juice and its percentage of dry grape sugar. Where the quality of substance permitted, I obtained the approximate percentage of juice in the grape, the percentage of ash in the juice, and that of acid, estimated as all tartaric acid. The latter results were obtained by titling Otto’s ammonia test solution for vinegar by means of dry tartaric acid, and using this test to determine the amount of acid above neutrality in the grape juice. I also determined the amount of extract left by evaporating the grape juice and drying it at 110° centrigrade, (a datum usually furnished in such analyses;) but I omit these results in the present report, as they are by necessity erroneous. Although pure dry grape sugar will bear the above temperature, it is different in grape juice. In every instance the sugar was strongly caramelized. When evaporated in vacuo, the juice has a pleasant and pure flavor of grapes; but the rapidity of the analysis prevented the adoption of this method.

The sugar was determined by Fehling’s copper test solution, of which the title was obtained by several determinations of its copper. In nearly every case of the sugar determination in this report, at least two were made for each specimen under examination, and none but accordant results were accepted.

The experiments were all performed upon the juice filtered through paper, and in every instance so rapidly that fermentation had no opportunity to impair the accuracy of the results. The grapes examined were derived from four sources: first, from the gardens of the Department; secondly, from the September exhibition of the Fruit Growers’ Society of Eastern Pennsylvania, held at Philadelphia, specimens having been collected by Mr. William Saunders, of the propagating garden of the Department; thirdly, two, specimens from Downingtown, Pa., through Captain I. R. Diller, of Virden, Ill.; fourthly, one specimen (Cuepern, No.9)from Mr. Charles J. Uhlmann, an experienced and scientific grape cultivator of Washington. This grape is interesting as a foreign specimen, having been imported by Mr. Uhlmann three years ago from Sans Souci, near Berlin.

An examination of the table will enable a comparison to be made of the different grapes, and by the aid of Mulder’s work upon the chemistry of wine we may also institute a comparison of these with foreign grapes. Mulder’s remarks relate to the highly cultivated wine grapes of Europe, of the great variety of which an estimate may be formed from his reminding us that Chaptal, when minister of the interior, caused 1,400 different species of vines to be transplanted out of France alone into the garden of the Luxembourg.

Regarding the percentage of juice in the grape, Berthier’s analysis of Chasselas and Pineau, grown in the neighborhood of Paris, shows a percentage, respectively, of 73.81 and 72.43.  Of the specific gravity of grape juice, Chaptal found, in that of the Cher and Loire, from 1.0627 to 1.0825, and Fontenelle, in 1822, from 1.029 to 1.1283. In the juice of the grapes of Stuttgard, 1.066 to 1.099; in that of Marbach, 1809, from 1.054 to 1.047; in 1811, from 1.084 to 1.074; in the Neckar district, 1.050 to 1.090, and near Heidelberg 1.039 to 1.091.  Respecting the percentage of sugar, Mulder gives from 10 to 12 for the percentage of total extract of the juice of fine purple grapes of Holland dried at 110°, which, of course, is not ail sugar. He estimates the sugar percentage of the wine grapes of Europe between 13 and 30, as follows, viz:

It is more important, however, to institute a comparison of the results of the present investigation with those obtained by other chemists upon. our native grapes, using the valuable reports contributed by Dr. C. T. Jackson and Dr. Antisell to the Agricultural Report of the Patent Office for the year 1859. Dr. Jackson analyzed thirty-eight specimens of native grapes collected principally by John F. Weber, who made a tour for that purpose, under the direction of the government, through several of the northern States. The same chemist also determined the amount of tartaric acid in pure native wine. Dr. Antisell examined the juice of the Catawba from the Ohio valley with special reference to the nature and amount of its acid. Dr. Antisell obtained by precipitation about one grain of bitartrate of potassa from each ounce of juice, and a percentage of 19.6 grape sugar. The grapes contained about 62½ per cent. of juice. Dr. Jackson found in the pure wine from 0.6 to 2 per cent. of tartaric acid, while my experiments performed on the juice before fermentation yielded from 0.817 to 1.754 per cent. of this acid. But one specimen of the grapes analyzed by me was of the same variety as those analyzed by the above-mentioned chemist, and the locality of my grapes was different, being of more southern latitude. It may, therefore, be of interest to compare the average percentage of sugar obtained by Dr. Jackson and myself.  The average percentage of sugar in the grapes analyzed by Dr. Jackson is 11.16, and in those analyzed by myself 12.5. I have calculated the percentage of juice in the grapes from Dr. Jackson’s report, and find the average to be 67.23, while in the grapes analyzed by me it is 79.11. Dr. Jackson measured the amount of juice obtained by pressing a pound of grapes, while I pressed variable weights, and calculated the percentage of juice from the weight of the moist residue.  The difference of method cannot account for a difference of 12 per cent. in the juice determination; consequently I infer that the grapes of the present report were richer in juice, which juice was richer in sugar tfian the grapes analyzed by Dr. Jackson. Whether this difference is due to a difference of climate, to a superiority of 1862 over 1859 as a grape year, or to such a difference in the grapes analyzed as could render a comparison by averages unfair, may be a matter for consideration.

In interpreting the results of such analyses, care should be taken to avoid drawing erroneous conclusions. One of the difficulties in analyses of this character is to obtain average specimens.  If a cluster of grapes is dryer or riper, if it has had the advantage of position upon the vine, its analysis would yield a result which could not be applied to the rest of the grapes upon the vine, much less to those of other vines. If the chemist could analyze specimens of the large quantity of must as it is prepared in actual vintage, the results would be certain for the average percentage of sugar; but as this cannot be done, he must content himself by multiplying the analyses and averaging the results. Care, therefore, must be taken not to draw more than general conclusions from the table of analysis. The numbers are accurate for the specimens examined, since they result from two accordant analyses of each specimen.

Analysis No. 14 gives a percentage of sugar 8.40 for the Montgomery grape. The portion analyzed was the lower half of a fine large bunch in good condition. The upper half was analyzed by the method of fermentation, and the percentage of sugar inferred from the alcohol produced was 12.12—showing a larger amount of sugar in the upper than in the lower half of the bunch. While the aid to be derived from chemistry by the vine-dresser, striving to introduce the most desirable vine, is great, the labor of such chemical investigation is also extensive. There is so much to be ascertained with respect to the constituents of the juice, and the methods of analysis are so imperfect, even with regard to important constituents, that . practical results can only be obtained by a systematic concert of action among chemists who shall confine themselves to the observation of certain points. What Mulder says respecting wine applies equally to the juice of the grape, viz: A chemical monograph on wine is at present impossible; in any age a single life would be insufficient for such a work.”

In continuing this subject next fall, I would suggest, first, that attention be confined at that time to the data of the table of analyses of grape juice in this report, with the exception, perhaps, of the percentage of ash in the juice, which involves delay in a long series of rapidly made analyses, and with the addition of such other examination as to ferment, nature of acids, &c., as time may permit after the establishment of the above-mentioned data; secondly, that attention be confined to the following grapes: Catawba, Norton’s Virginia, Delaware, Concord, and Mottled, seeking to analyze as many specimens of each from as many different localities as possible, obtaining average specimens from different vine-dressers who may be willing to communicate to your department their experience as to the cultivation, soil, climate, &c., influencing the crop, and subsequently as to the wine manufactured from the grape, which may also then be examined chemically and compared with the original juice; thirdly, I would invite the co-operation of all chemists residing in or near the wine regions, and who feel sufficiently interested in the subject, to analyze the juice of the above-mentioned grapes as to the named data, and to communicate their results to your chemist either before or after publication by themselves, when they will receive due credit, in your chemist’s report, for their scientific labors. And since the filtering of pure grape juice through paper is a very tedious operation, impeding very much the rapidity desirable in a research where many specimens of grapes should be examined immediately on their reception, I would suggest that in the proposed examination the juice be zot filtered but strained, and suffered to stand in large tubes for an hour or two until the gross matter in suspension shall have settled. The finer particles left in the liquid would probably affect the result less than the possible change by exposure to the air while filtering, and at the same time the liquid examined would more closely approach the character of the must actually fermented in practice.

The determination of sugar in grape juice affords, other things being equal, a criterion for the alcoholic strength of the resulting wine. As 180 parts of grape sugar are equivalent to 92 parts of alcohol, a larger percentage of alcohol in the wine than half the percentage of sugar in the juice is impossible, unless either sugar has been added or the must concentrated by evaporation. Wine must be not only sufficiently strong in alcohol to keep well, but of such a character, in respect to acid and aroma, as not to be unpalatable. It results from the analyses, given and quoted in this report, that in general the grapes examined have too little sugar and too much acid in the juice for a desirable wine. Though good wine is made in some sections of our country from the pure juice of the grape, in other localities the addition of sugar to the must is extensively practiced. Hence the problem which the American vine-dresser has to solve is, to produce a healthy vine which shall bear fruit improved in these particulars.

There is no doubt that we have the climate in our extensive country to produce any given class of wines, and the climate of any given locality will necessarily influence the nature of the wine which may be made profitably in that locality. It cannot be long before the classes of vines suitable to our different climates shall be established; consequently chemical investigations of the juice of the fruit of those promising most for wine purposes is at the present time of great importance.

While this investigation is in progress, Dr. Gall’s method of improving wine possesses a peculiar interest. Many years ago Liebig was much blamed (as countenancing adulteration) for suggesting to a society of vintners in Germany the addition of grape sugar to their must of a year very unfavorable for wine.  Even now Mulder places himself "unconditionally on the side of those who consider everything added to or taken from the fermented grape juice (even the clearing it with albumen or isinglass, or the addition of substances containing tannic acid, in order to supply a deficiency of that acid) as adulteration.” This would seem to be a refinement of purity; for if the wine contains nothing deleterious, keeps sufficiently well, and is of satisfactory flavor, it would appear to be immaterial whether it received its original sugar by the hand of man directly, or by being placed by man (in the vine) in such a condition that it could secure its saccharine matter indirectly by aid of the sun. While vine-dressers are improving the grapes of our country, vintners may surely be urged to seek to improve the available wine by methods which promise as well as that of Dr. Gall. Since in many sections the custom is prevalent of adding sugar to the must, it would be better, in this addition, to employ a systematic plan of operations.

To employ this method of improving wines, it is necessary to learn the percentage of acid and sugar in the must, so as te bring it, by the addition of grape sugar and water, up to the constitution of a standard must, containing 9.65 per cent. of acid and from 26 to 28 per cent. of sugar. This involves an analysis to be made by the wine-maker. It is probable that the instruments for these operations may be so improved as to place the analysis within the ability of vintners, and this subject ought to receive attention. It would be much more difficult, perhaps, to bring such instruments into use; but this difficulty might be obviated by the Department placing a certain number of such instruments in the hands of experienced vintners whose operations are extensive, upon the condition of employing them and furnishing to the Department the results of their operations, together with the wine, for analysis. By this means not only would reliable information be gained as to the practical working of Dr. Gall’s method upon American musts, but the instruments themselves would be subjected to a test, in the hands of those who are to use them, which would show what was needed for their farther improvement.

Finally, in employing Dr. Gall’s method, pure grape sugar and not cane sugar should be used. There is no difficulty in manufacturing this article in our country, and it will be made if found useful for wine purposes. Until such manufacture shall be established, the article in question may be imported from Germany.

About twelve years ago Count de Montigny sent from China to the Geographical Society of Paris a collection of seeds, among which were those of the sorghum. Of these seeds a single one germinated; its product was distributed, and the next year a gardener who had received some of them sold his crop of eight hundred seeds to Vilmorin, Andrienx & Co., of Paris, for a franc apiece. Through care and attention the new plant rapidly acquired notoriety, and many experiments upon it were instituted in Europe, both by scientific and practical men.

In the United States Patent Office Agricultural Report for 1854, page 219, the new cane is introduced to our country in the following words:
“Researches on the Sorgho Sucré—A new graminaceous plant, which seems to be destined to take an important position among our commercial products, was sent, some four years since, from the north of China by M. de Montigny to the Geographical Society of Paris. From the cursory examination of a small field of it, growing at Verrières, in France, in autumn last, I was led to infer that, from the peculiarity of the climate, and its resemblance in appearance and habit to Indian corn, it would flourish in any region where that plant would thrive. But how far it will subserve the purposes ascribed to it in France, should it even succeed in any part-of the United States, can only be determined by extended experiments.”

The writer of the above, Mr. Browne, brought with him to the United States some of the seed of Mr. Vilmorin, which was distributed by the Patent Office to numerous persons throughout the country. In 1850 Mr. Leonard Wray, a practical sugar-planter, visited Kaffir-land from the East Indies, and found the imphee, around the huts of the natives, cultivated for chewing. Having become satisfied that the plant was valuable from its saccharine properties, he returned to Europe and planted it in England, France, and Belgium.  He memorialized the French minister of war upon the subject, and exhibited the plant and its sugar to Mr. Buchanan, then American minister in London. He subsequently cultivated the imphee in Turkey, Egypt, the West Indies, the Brazils, the Mauritius, Australia, and finally in this country. Instead of one variety, as we have, of the Chinese sugar-cane, he has discovered among the Kaffirs no less than sixteen distinct kinds of imphee, of various degrees of saccharine richness, and differing very widely in the time required for their maturity.  In 1856 Mr, Wray obtained the silver medal of the Paris exhibition for his imphee sugar, alcohol, seeds, and plants, and the French government granted him twenty-five hundred acres of land in Algiers for the prosecution of his investigations in the cultivation of this plant. (Olcott, pp. 26, 27.)

At the Rockford (Illinois) sorgho convention it was resolved that, in the estimation of the convention, there are only three kinds of cane, viz: Chinese sugar-cane, having black seeds growing in prongs from two to seven inches long; the second or tufted variety, to be known as African; and the third variety, lately introduced, known as the Otaheitan, having long heads from seven to twelve inches in length and from one to two in thickness.

Mr. M. Day, jr, has communicated to me the following account of the Otaleitan cane:
The seed was received from the Patent Office, in the year 1859, by P. Heaveland, of southern Illinois, and passed from him to R. Hooper, of Schuyler county, Illinois, who cultivated the plant, and distributed the seed principally in his neighborhood; but last year gave it a more extended circulation. In the hands of those boiling down the juice of this cane, the sugar crystallizes a few hours after the strike is made. Mr. Cory, of Lima, Indiana, has obtained ten gallons of sirup from 1,200 pounds of cane, and nine pounds of crude crystallized sugar from twelve pounds of sirup. The seed is rather flat than round, the husk or outside of the seed being of a very dark purple.  The joints of the cane are closer than in sorghum, and the stalk is tall. The stalk does not tiller out, but each seed produces one stalk. The general impression is that this plant is of the variety of imphee called Oom-se-a-na, or a derivative of the same, as it differs somewhat in appearance from that cane.  Others, acquainted practically with this cane, believe it to be not imphee, but a different cane derived from the island whose name it bears.  No specimens of this cane have been received at the laboratory, although its sugar has been analyzed.

In the United States the question of the new sugar cane, before the rebellion, received considerable attention, both from the government and from private individuals. In the Patent Office agricultural reports from 1854 to 1861, and in the present report of the Department of Agriculture, there are several articles from scientific and practical men, by which the progress in our sorghum experience may be followed. Drs. Jackson, Hayes, and Lawrence Smith have there examined the subject chemically, while several farmers have recorded their valuable practical experience upon the culture of the canes and yield of sirup. Whoever may desire to possess the information upon this subject in a connected form, may do so by means of the excellent work upon sorgho and imphee, by Henry S. Olcott. The increase of prosperity and population due to a continued peace, together with the gradual relative decline of the beet sugar manufacture in France since the dynasty of Louis Philippe, with other causes, affected. the relations of sugar supply and demand in such a manner as to concentrate much attention upon the new canes everywhere.  Upon this came the rebellion to intensify, in the United States, this attention.  Extensive areas in different sections of the northern States were planted, machinery was proeured for crushing the cane and boiling down the juice; conventions of sorghum planters and sugar manufacturers were held, and newspapers, devoted to the specialty of the new canes, were established. In the west the interest taken in the sorghum question has been especially great. In this section of our country the demand for molasses has always been large, and the farmers, observing in the new cane a means of supplying this demand by their individual labor, did not hesitate to plant lurgely.  Letters received by the department state that in the localities of the writers the wholesale grocers purchased no sugar-cane molasses last fall.

Under these circumstances an examination of the sorghum and imphee became a matter of paramount importance in the laboratory of the new department.  The same causes which operated for delay in receiving specimens, and for a rapid analysis of the specimens when received, in the case of the grapes, obtained with the sorghum and imphee.  I cannot regard the examination, of which this is a report, in any other light than a preliminary one to more extensive operations next fall, and I would suggest that the department take early measures for procuring proper specimens for examination.  It well then to determine the ash of the plant and the constituents of its juice— cane sugar, grape sugar, gum, &c. Some of the specimens received for the present investigation were packed without ventilation, and thereby were lost by fermentation. I have to regret the loss in this manner of a valuable box from Isaac A. Hedges. Two other boxes were unavailable from having had no labels upon them or upon the specimens, or any other means of identifying them. In preparing specimens of cane for the laboratory they should be cut off close to the ground, and topped o as to leave them one joint longer than is usual when they are to be pressed for sugar boiling. They should be distinctly labelled with the owner’s name and residence, kind of soil upon which the crop grew, nature of the seed, and a statement as to the origin of the seed.  With each different specimen of cane a specimen of the seed should be sent, securely tied to the specimen. Some of the specimens of cane received were cut into short pieces, in the ends of which fermentation had commenced, so that only the middle joint of each could be analyzed.  Some of the specimens were completely valueless on this ground. Others had to be rejected front the broom corn deterioration as shown by their seed. The subjects of analysis in this report were the juice of the fresh sorghum and imphee, the manufactured sirup, and the manufactured sugar.

The lower portion of the cane was used for the extraction of the juice, which was obtained by a hydraulic press capable of effecting a pressure of 10 tons. The cane was cut into lengths of eight inches with a tobacconist’s knife, and every piece was minutely inspected, so that none but unfermented cane should be employed. To the juice milk of lime was at once added, until a weak alkaline reaction was manifested; it was then raised to the boiling point, and at once filtered and cooled down to 20° centigrade, when the specific gravity was determined. One specific gravity bottleful was immediately operated upon for the determination of grape or uncrystallizable sugar by Fehling’s copper test; while another bottleful was exposed to a temperature of 100° centigrade for two hours, with the addition of 9 drops of pure oil of vitriol, to convert the cane sugar to grape sugar. At the expiration of this time the acid was neutralized by carbonate of soda, and the grape or uncrystallizable sugar was again determined. From these data the percentage of the two sugars was obtained by calculation. The juice presented a similar appearance in the different canes. It was colored more or less of a yellowish green color, and had more or less of whitish sediment. This sediment, by the microscope under polarized light, showed small globules, which did not exhibit the black cross peculiar to starch. The sediment was, after boiling, rendered blue or light violet by tincture of iodine. In some cases the sediment did not react with iodine like starch. Lime, when boiled with the juice, separates a greenish feculent matter. The fresh juice of the cane, without addition of lime or heat, filtered through paper very slowly. It reduced the copper of Fehling’s test when boiled with it. In these analyses the cane sugar percentage may be subject to a small reduction from matters in the defecated juice capable of being converted into grape or fruit sugar by sulphuric acid. The same result would obtain employing the optical analysis. On the other hand, this error would be diminished by the slowness with which the last portions of cane sugar are transformed by acid, (see Fehling’s experiments,) so that a small part of the cane sugar escapes determination. Without taking into consideration this loss of cane sugar by incomplete action of the acid, I have estimated by the result of a particular experiment, (to be described in its proper place,) that the excess of cane sugar in my analysis is probably not more than one half per cent. In future experiments this point should receive attention, as it is important, in the practical questions arising from the sugar manufacture, not only to know exactly how much cane sugar is really present, but what is the nature and amount of the gum-like bodies accompanying the sugar.  I regret that circumstances made it impossible for me to bestow more attention than I have done upon this portion of the subject at the present time. The specimens of cane, sirup and sugar have been numbered in the order in which they have been received in the laboratory.

When pressed the cane emitted a whitish green, turbulent liquid of acid reaction to litmus, and which reduced Fehling’s copper test solution when boiled with it. The juice appeared under the microscope as a transparent liquid with small, irregular, but roundish, cells floating in it, which cells did not exhibit the black cross of starch with polarized light. This juice could not be filtered readily as many of the cells passed through Swedish filtering paper. The juice was coagulated by heat, and the cells broken up, which permitted a slow filtration through paper of a loose texture. With tincture of iodine the following reactions were observed. The fresh unfiltered juice gave a blue color.  The white sediment, boiled with tincture of iodine, gave also a blue color.  The boiled filtered juice gave, with the same reagent, a violet color. When boiled, with the addition of milk of lime, the juice acquires a yellowish color, a green, slimy, feculent matter is separated, and the juice filters rapidly. The filtered liquid exhibits no bluish color with tincture of iodine; the greenish sediment on the filter becomes brown with that reagent. When thin horizontal sections of the fresh cane werp observed by the microscope, numerous cells, filled with a transparent liquid, were observed. Scattered over the field were points which are sections of the long fibres which pass from joint to joint.  Sections of the cane dried in vacuo exhibited the same appearance, the cells being shrivelled and empty, and the section of the fibres with yellowish matter encrusting them. No crystals were observed. When water was added to the specimen, the section of the long fibres presented the appearance of a section of four tubes, thus: . Sulphuric acid, added to the slice, gave a brown color, which was more intense around the fibres. Tincture of iodine gave a blue color intenser about the fibres. When a slice was boiled with Fehling’s solution, it was colored red. When examined with the microscope, the color appeared yellowish, and was more concentrated around the tubular fibres.  Pieces of the cane, boiled with Fehling’s solution in a test tube, reduced the copper solution with a red deposition of suboxide of copper. As but few microscopic examinations of the cane were made, they may be all reported in connexion with analysis No. 1.

A specimen from analysis No. 13, which had been kept in a cool, damp room until fermentation had set in, gave the following results: It broke very readily at the joints; freed from bark it appeared somewhat translucent, like a frosted potato; the juice was very acid; a cross section, under the microscope, presented the same appearance as specimen No. 1, except that the cells were filled with liquid; no starch reaction was afforded by the use of iodine. A slice boiled with Fehling’s solution became red from reduction of copper, some of which was deposited on the watch-glass. This slice, examined under the microscope, showed an intense reddish yellow color about the longitudinal fibres which pass from joint to joint. The brown color given by sulphuric acid was also concentrated around these filaments.

A cane, from those used in analysis No. 5, was placed in a warm dry room; when examined, it was found to be perfectly dry in the extreme joints, and partially dry in the middle joints. The central joint had changed to a deep red color on the bark, which color had penetrated the pith of the cane, leaving a small portion along the axis white. The outer joints had almost the whole pith white. By the microscope, cross and vertical sections of an inner joint showed the color concentrated along and in the longitudinal fibres, which were of this appearance—

Nos. 2, 3, and 4 were received October 22 from H. D. Emory, Dixon, Illinois, and analysed Nevember 17 and 18.

No. 2, grown from pure black sorghum seed, at Jacksonville, Illinois, upon a sandy soil two feet deep, over blue clay. The expressed juice, treated with a few drops of milk of lime to a slight alkaline reaction, then boiled and filtered from the coagulum, yielded a clear, slightly brown liquid, appearing, by the addition of the tincture of iodine, of a deeper brown color. In almost all of these experiments two analyses were made of the defecated juice, and none hut accordant results were accepted. This juice had a density of 1.068, and contained 8.02 per cent. of uncrystallizable, or grape, sugar, and 5.75 cane sugar.

Carbonic acid gas was passed through the juice remaining after the analysis; it was then filtered through bone black, and evaporated in vacuo; yielded a lemon-colored, sticky mass, which had a most agreeable flavor.  This experiment was instituted for obtaining the taste of the sirup; and notwithstanding the degrec to which the evaporation had been carried, on December 20 it had granulated in minute crystals, which, under the microscope (with a power of 500 diameters) exhibited clearly the form of cane sugar.

No. 3. Sorghum grown upon a sandy soil over shaly limestone. These canes yielded to pressure a reddish juice, in which, by the microscope, could be seen a few small cells floating.  The addition of tincture of iodine gave no blue color when added to the juice.

An experiment upon this juice showed that the percentage of uncrystallizable sugar was not increased by keeping, the expressed and limed juice twenty-four hours. Like all cane juice this had an acid reaction. The cane was very red on the outside.

No. 4. Red imphee, two or three weeks earlier than Nos. 2 and 3. This specimen was examined before 2 and 3, and before the arrival of my hydraulic press. The juice was obtained by wringing four, stalks containing three joints each. It was a green turbulent liquid of slight acid reaction, giving a greenish brown precipitate with iodine; specific gravity, 1.062. By evaporating the juice at a temperature of 100° centigrade, 15.96 percentage of residue was left; but it was difficult to obtain a perfectly dry residue. The percentage of uncrystallizable sugar was 12.24 by Fehling’s test.  It contained no cane sugar whatever.  Though sensible of no error, I repeated the analysis of this cane a few weeks later, when I obtained, as might be expected from evaporation having taken place, a juice richer in saccharine matter, but containing no cane sugar. The latter analysis gave: specific gravity, 1.072; uncrystallizable sugar, 15.71 per cent. I repeated this analysis a day later upon another portion of the same juice, and obtained the same percentage of uncrystallizable sugar. Sections of this cane were perfectly fresh-looking, and could not be distinguished in appearance from those sections of canes which were rich in cane sugar.

Nos. 5 and 6, from J. H. Smith, Quincy, Illinois; grown upon black prairie soil. (?) Mr. Smith states in a letter to the Department that he imported his seed from France last spring, and that he has been successful with the cultivation of the cane, especially with the Nee-az-a-na. I have received in the laboritory the following seeds from Mr. Smith:
Specimen No. 1, labelled Chinese cane seed.
Specimen No. 2, labelled Imphee Nee-az-a-na.
Specimen No. 3, labelled Boom-a-wa-na.
Specimen No. 4, labelled Oom-see-a-na.
Specimen No. 5, labelled E-éng-ha.
Specimen No. 6, labelled Boom-ee-a-na.
Specimen No. 7, labelled Koom-ba-na.
Specimen No. 8, labelled Zum-ba-ya-na.

A portion of the juice, defecated by lime and filtered, was concentrated in vacuo. In nineteen days it had crystallized.  By the microscope, the crystals were transparent and colorless, polarizing the light with beautiful colors (exhibiting the colored rings in some crystals) and distinctly of the form of cane sugar. It is important to note that the purified juice of this cane yielded a sirup of very pleasant flavor, so pronounced by many of the visitors to the laboratory.

Nos. 7, 8, and 9, were received from H. M. Carter, Lafayette, Tippecanoe county, Indiana. Another specimen, grown by Mr. Pfromer, was received in this lot, but it was spoiled, and had to be rejected.

The two following specimens were received from W. W. Corbett, editor of the Prairie Farmer, Chicago, Illinois.

No. 10, of the variety known as White Imphee, was grown by Knox Taylor, of McLean county, Illinois, upon common high prairie soil. It was planted in hills, and cultivated like corn. It yielded a rather clear juice of a lemon color, which gave a very slight coagulum when defecated by lime. Tannic acid gave a slight precipitate with the defecated juice.

I added to twenty-five cubic centimetres of the defecated juice an equal volume of ninety-four per cent. alcohol. No precipitate took place. On the addition of another equal volume of alcohol, a white precipitate fell, which, on being washed with a mixture of two volumes of alcohol of the above strength and one volume of distilled water, diminished to a slight residue. The residue blackened by heat and left an ash. Heated with sulphuric acid and subjected to Fehling’s sugar test, it gave no precipitate of suboxide of copper. There was not enough juice at my disposal to pursue the subject, any further.

No. 11, grown by K.H. Fell, upon similar soil with similar cultivation, and in the same county as in the case of No. 10. Neither of these specimens presented a good appearance externally, but the inner joints appeared perfectly sound. Notwithstanding their appearance, it will be seen that their relative proportion of cane sugar is large.

A particular experiment was performed upon the juice of this cane, to ascertain what effect the gum in it would have upon the accuracy of the determination of the cane sugar. Five times as much of the juice (purified by lime) as was employed for analysis was precipitated by two volumes of 94 per cent. alcohol and washed with undiluted 94 per cent. alcohol.  The precipitate was mostly soluble in warm water, and a portion, burned to ash, left much lime. One-fifth of it was dissolved in water and treated with sulphuric acid at the temperature of boiling water, being subjected to the same operations as the sorghum juice when tested for cane sugar. The precipitate by the boiling Fehling’s solution, though red, had not the distinct character of suboxide of copper, being flocculent. I therefore determined the amount of suboxide present in the precipitate by analysis, and obtained a result showing that 0.08 per cent. must be deducted from the percentage of cane sugar as found by ordinary process. 6.678 was found, which was corrected above to 6.60.

The juices of Nos. 14 and 15 were fermented for the production of alcohol. The juices of the two varieties of cane were mixed and contained about 12 per cent. of uncrystallizable and cane sugar together.  Five pints were fermented with brewer's yeast.  The fermentation proceeded regularly and speedily to the end, when the wash was distilled and rectified, yielding nine and three-fourths fluid ounces of 60 per cent. alcohol and seven and one-fifth fluid ounces of 5 per cent. alcohol. The alcohol had a very pleasant flavor and aroma, and has met with the warm approval of judges of the article.

In this connexion the alcohol of Rev. A. Myers, of Springfield, Ohio, may be noted. The specimen was received December 30, 1862—was colorless and of good flavor, with the exception of being somewhat still-burned. It contained 50 per cent. of alcohol by volume.

Some of the specimens of sirup sent to the department were lost for analysis from having no labels upon them by which they could be identified. In almost all of the specimens received there was a deposition of cane sugar in the vessels. Since I could not tell from any information at hand whether the sirup was placed in the vessels in an uncrystallized condition, I did not endeaver to estimate the proportion of crystals to sirup; but was contented with an examination of the crystals by the microscope, and, with an analysis of the clear sirup, to determine the amount of uncrystallizable sugar and cane sugar in solution. The analysis was performed as upon the cane juice.

Nine specimens of sirup were received from L. Bollman, of Bloomington, Indiana.  The cane was grown in Munroe county of that State, upon soil bearing the general character of a clay loam, with more or less sand in it, and resting upon a limestone formation.  On page 140 of this Agricultural Report will be found Mr. Bollman’s article to which reference may be made for a more particular description of the specimens of sirup analyzed.

Numbers 1 and 2.—Sirup by L. Bollman from two separate crops of mixed sorghum and imphee cane, cut towards the end of October, the sugar having been made in the beginning of November. The sugar sediment occupied one-third the length of the bottle.  Mr. Bollman states that granulation commenced in four days. All of the simps sent by Mr. Bollman were manufactured upon Cook’s evaporators, except No 3, in which a common sheet-iron pan was employed. The crystallized cane sugar sediment was examined by the microscope, to determine its form of crystallization. I expended several days upon this work of comparison, having prepared grape and fruit sugars from raisins, having selected fine specimens of crystals from rock candy, and having procured raw sugar of the Louisiana cane. By careful examination of the crystals under the microscope, causing them to rotate in different directions by moving the glass cover of the microscope slide, and by comparing the results with the forms exhibited by known crystals of grape and cane sugar, and with those delineated by Rammelsberg in his crystallographic chemistry, I became satisfied as to the nature of the sugar.

Cane sugar and grape sugar crystallize in different forms, the former plainly in an oblique prism, modified in different ways according to the laws of crystallography; the latter crystallizes with difficulty in wart-like masses, which are composed of needles or laminæ.  Wherever crystallized, sugar is mentioned in this report as having been observed, whether the article was prepared by myself from the juice, or furnished to the Department as raw sugar or floating in sirup, I recognized the form of cane sugar. In nearly all of the sirups examined I detected crystals of cane sugar by the microscope. These crystals appear under the microscope colorless by white lights, and colored by polarized light, showing beautifully in many cases the colored rings belonging to cane sugar. In the following experiments on sirups the clear sirup was taken from the top of the bottle, and its freedom from crystals of cane sugar ascertained by the microscope. Where crystals were observed the sirup was filtered by the aid of atmospheric pressure, using the air-pump. The results, therefore, of percentage of sugar refer to sugar in a state of solution. I refer to the table on page 526 for the results of the analyses of the different sirups.

Number 3—Mr. Craig’s Chinese cane contained a flocculent sediment mixed with crystallized sugar, occupying one-half the length of the bottle. The seed was planted on the last day of April, on moderately good soil, with sand and gravel beneath. The cane was cut towards the end of October.

Number 4―Sirup of Chinese cane, grown by Charles Wier, upon land of which the brush had been burned, yielding a soil abounding in potash.  Planted on the 15th of May, and cut at the end of September. A few scattered crystals of cane sugar were found in the bottom of the bottle.

Number 5—By Charles Swearingen. Chinese cane sirup with crystals of cane sugar scattered through it. The cane was planted 1st of May, and was cut a few days later than No. 4.

Number 6.—Sirup from white seed imphee cane, planted by A. Wier upon good soil which had produced only four crops. The seed was planted 1st of May, and harvested when the cane was red. One-quarter of the length of the bottle contained a sediment of crystallized cane sugar mingled with some vegetable tissue. This sirup did not exhibit any crystallization before leaving Mr. Bollman’s possession.

Number 7—Same seed, by A. Wilson. This is a light sirup, and contains a sediment of light-colored crystals of cane sugar, extending half the length of the bottle.

Number 8—By Mrs. Sharpe, same seed; crystals of cane sugar, occupying not quite one-third the length of the bottle. The sirup is of a fine color.

Number 9—From Mrs. Sharpe. The bottle is labelled Chinese, and is the mixed product of several lots of canes. Crystals of cane sugar occupied one-third the length of the bottle.

Number 10.—Sorghum sirup, from S. O. Stephens, Oneida, Knox county, Ill.  This specimen exhibited, by the microscope, one or two crystals of cane sugar.

Number 11—From J. H. Smith, Quincy, Illinois; sirup from imphee, (Nee-az-a-na.) A sediment of crystallized cane sugar occupied half the length of the bottle.

Number 12.—From the same. Sorghum sirup, containing a few crystals of sugar at the bottom of the bottle.

Number 13.—Sorghum sirup, from Mr. Reily Root, of Galesburg, Illinois, and grown upon clay soil. Defecated by the use of clay, and purified by charcoal. The sirup had a slight flocculent precipitate in it; was of clear amber color, and solidified to crystals of cane sugar when a drop was exposed to the air.

Number 14—Sorghum sirup, from S. W. Arnold, Cortland, Illinois. A clear sirup of good color and flavor.

Numbers 15—18.—Four specimens from the Chicago Steam Sugar Refinery, comprising first and second qualities of Illinois raw sorghum sirup, and first and second qualities of the refined sirup. The improvement in color and flavor is very marked in the refined specimens.

Number 19.—New Orleans molasses, bought in Washington, and analyzed for the purpose of comparison.

The sugars from sorghum and imphee were analyzed by the same methods pursued with the juice of the cane and with the sirup. They all possessed most distinctly the crystal form of cane sugar.

No. 1.—Imphee sugar, extracted by myself from the sediment of bottle No. 7 of sirup, (see analysis of syrup.) This sugar was drained from the sirup, boiled once with 94 per cent. alcohol, drained, pressed, and dried.

No. 2—Sorghum sugar, from John L. Gill and son, Columbus, Ohio. Of fine color, large grains, and appeared to have been washed.

No. 3.—Imphee sugar of dark color, made by J.H. Smith, Quincy, Illinois, in ten days from the strike. This sugar was the same as in the sediment of sirup No. 11, and was made from the juice of Nee-az-a-na, No. 6, of my analysis of sorghum cane.

No. 4.—This specimen was made by the same person from the same cane.  It was of fair color. The specimen analyzed was furnished by the Illinois State Agricultural Society, No. 1 of their convention, as a sample of 100 pounds received by them from the maker. No chemicals were used in the manufacture.

No. 5—Presented by James Whitehill, Zanesville, Ohio, sorghum. sugar, well crystalized, and of a good color for raw sugar. When boiled with 94 per cent. alcohol, and submitted to the microscope, the grains were shown to be composed of smaller crystals of the form of care sugar.

No. 6.—Sugar from the so-called Otaheitan cane, presented by Isaac A. Hedges, Chicago, Illinois. A very fine article of raw sugar, and well granulated, the crystals appearing as No. 5.

No. 7.—Sorghum sugar, made by Joseph H. Steed, and presented by Mr. Day, jr.; of Mansfield, Ohio, as sugar No. 29 of the Ohio State Sorghum Convention. A dark sugar, but well crystallized, and not to be distinguished under the microscope from the New Orleans sugar, No. 9.

No. 8.—Presented by the above as No. 18 of the above convention, sorghum sugar, made by C. Cory, Lima, Indiana. The specimen was of good color, and well crystallized.

No. 9.—New Orleans sugar, presented by M. Day, jr., of Mansfield, Ohio, and submitted to analysis for the purpose of comparison with the sorghum and imphee sugars. It was rather dark and sticky.

No. 10.—This sugar, together with Nos. 11, 12, and 13, was presented by the Illinois State Agricultural Society for examination as specimens of imphee sugar. No. 10 was made by David Brown, of Rushville, Illinois. A little soda had been added to the juice in boiling. The sample was part of a lot of seventy-five pounds of sugar. It was of very fair color.

No. 11.—A sample of twenty pounds of imphee sugar, which was manufactured by H.R. Smith, of Quincy, Illinois, without the use of any chemicals.

No. 12—By C. D. Roberts, of Jacksonville, Illinois, made without the use of chemicals; of very fair color.

No. 13.—Was made by D.S. Pardee, of Rockford, Illinois. Rather dark sugar, but of good grain.  Lime water was poured upon the sugar while dripping.

No. 14.—This specimen of sugar was interesting as a sample of that made by Mrs. Hooker, of Schuyler county, Illinois, from the Otaheitan cane. It was of excellent grain, color, and general appearance.

No. 15—Another specimen of Otaheitan sugar, from the maker, C. Cory, of Lima, Indiana. This sugar was by far the finest in appearance of any received by the Department, and its analysis justified its fair appearance.

No. 16.—This was a specimen of the beet root sugar now being manufactured in the west.  The name Marshall was written upon the bottle, and the sample was accompanied by a copy of the New York Times of January 23, giving an account of the operations of Mr. Belcher, of Chicago, and the Illinois Central Railroad Company in introducing the culture of the sugar beet along the line of the above mentioned railroad. It is supposed that No. 16 was a specimen of the sugar alluded to in the Times.

No. 17.—Sorghum sirup, made by Rev. A. Myers, of Springfield, Ohio. This specimen was one of the most remarkable I have examined, from the fact of its containing a large proportion of crystallized grape sugar. Mr. Myers states that no addition was made to the juice of the cane, but that it was defecated by long boiling and by careful skimming. The canes were select, perfectly ripe, and had been cut two weeks before pressing. They grew upon a rich, sandy, limestone soil. The sirup was of clear amber color, with six or eight crystals of cane sugar at the bottom of the bottle, very distinctly characterized by the microscope. After standing for several days a precipitate began to form at the top of the bottle, and gradually extended downwards until the whole mass of liquid was solid, and could be turned upside down without displacement. The microscope revealed the crystal form of grape sugar. A portion of it was spread upon a brick to dry, and this dried portion was analyzed, yielding 64.11 per cent. of grape sugar, thus confirming the microscopic results.  This is the only specimen of crystallized grape sugar that I have found in the sirup from the new canes. It was readily detected by the microscope, and no doubt was derived from the cane and fruit sugar in the juice by the mode of manufacture.

No. 18—This specimen was pure white refined cane sugar, purchased in Washington, and analyzed for the purpose of comparison. I found it almost perfectly pure; it left no ash whatever when burned, and contained no hygroscopic moisture. It yielded the small amount of 0.84 unecrystallizable sugar, from which may be inferred that its organic analysis would have given the percentages of carbon, hydrogen, and oxygen belonging to pure cane sugar.

Having given in the preceding pages the results obtained in the laboratory of the Department by an examination of the juice, sirup, and crystallized sugar of the new canes; let us now compare these results with those obtained by others, for the purpose of eliciting what practical information we may upon the subject of sorghum and imphee. If any such were needed, the experiments establish beyond a doubt the existence of crystallizable cane sugar in the juices of sorghum and imphee; but I consider the question settled by the experiments of others before those of the Department were instituted, and allude to the subject only because it was seriously and strongly asserted, at the Ohio State Sorgho Convention, that the crystals obtained by treating these juices are those of grape and not cane sugar. It may be well, therefore, for the benefit of practical farmers to st forth, in as plain language as the subject permits, wherein cane, grape, and fruit sugars differ. Among the many sugars known to chemists, these three are by far the most employed in common life.

1. Cane sugar occurs in the ordinary sugar-cane, in the sap of the maple, and the juice of the beet, without the admixture of any other kind of sugar.  It crystallizes readily from a pure solution, in large oblique prisms. It rotates the plane of polarization to the rights It does not precipitate suboxide of copper from an alkaline solution of that metal (Fehling’s test) at the boiling temperature. By being heated with acids, or by being boiled for a long time with water, it is converted into a mixture of grape and fruit sugar.

2. Grape sugar, or glucose, constitutes the white powder seen upon the outside of old raisins; it also forms the sediment arising in old honey. It is found in connexion with cane and fruit sugars in many fruits, and may be made artificially by the action of acids upon cane sugar, starch, or wood.  Made thus it is used in Europe for adding to wine musts which are weak in sugar. It crystallizes with difficulty, forming cauliflower-like masses which, under the microscope, appear like fine needles or blades, and in some conditions as six-sided tablets—(Gmelin.) It also polarizes to the right, but to a less degree than cane sugar. It is less sweet than cane sugar, one pound of the latter producing the same degree of sensation of sweetness as from two to two and a half pounds of grape sugar. At the boiling temperature it precipitates the copper of Fehling’s test. While cane sugar has to pass into grape and fruit sugars before fermentation takes place, grape sugar ferments without further change.

3. Fruit sugar occurs, as its name partly implies, in acidulous fruits with grape and-cane sugars. It occurs also in molasses, as before stated. It is not capable of crystallization, but exists as a sirup, or, when dried, as a transparent candy. It is as sweet as cane sugar. It rotates the plane of polarization to the left. At the boiling temperature it removes the copper from Felling’s test solution, like grape sugar. It ferments without passing into any other kind of sugar. These are the most prominent differences between the three sugars.

As “polarization to the right or left” cannot be sufficiently explained without many words, the unscientific reader is requested to accept, in the above description, that “cane, grape, and fruit sugars behave differently towards polarized light.”

A great want of clearness rests in the public mind as to grape and fruit sugars, arising from the carelessness with which scientific men use the terms, employing the words “grape sugar” or “uncrystallizable sugar” either to pure grape sugar, to pure fruit sugar, or to a mixture of the two. The mixture of grape and fruit sugars arising from the action of acids, ferment, or water upon cane sugar is called “inverted” sugar, “grape” sugar, and “uncrystallizable” sugar; being thus named differently by different persons.  "Inverted sugar” is the proper name, which is derived from the change of action upon polarized light from right to left. I have called the grape or fruit sugar of the sorghum “uncrystallizable sugar” in this report, since, whether it be pure fruit sugar, or whether mixed with a little crystallizable grape sugar, it is uncrystallizable to all the practical purposes of the sugar-maker.

The practical results of our present chemical knowledge of the sugars may be briefly stated, as follows: Grape sugar is practically uncrystallizable in the manufacture of cane sugar, as it remains in the molasses; it is also much less sweet than cane sugar. Fruit sugar is as sweet as cane sugar, but does not crystallize. Cane sugar may be transformed into inverted sugar (which is a mixture of grape and fruit sugars) by means of acids, long boiling with water, and fermentation, &c.; but neither of these last sugars can be changed again into cane sugar by any process known in chemistry. For practical purposes the difference of composition of the three sugars, as shown by their organic analyses, need not be discussed here; it is, however, important to note that they form compounds with salts, and that these combinations with the salts naturally in the vegetable juices associated with the sugars do not crystallize. In the compound of came sugar with lime the cane sugar is not destroyed or “inverted” by boiling, but grape or fruit sugar in combination with lime are rapidly destroyed by boiling.—(Souleiran.)

Let us now proceed to an examination of the results of the chemical investigations upon sorghum and imphee, commencing with the sugars, and proceeding through the sirups to the juice of the cane.

The sugars were analyzed without having been first dried.  As will be seen by reference to the table on page 528, they contain a large percentage of cane sugar, some uncrystallizable sugar and water. They vary in color from dark to quite light, and do not contain, as far as my experiments go, any substances preventing a proper refining process to be effected upon them. The following table of the analyses of 50 (dry?) specimens of raw sugar by Pelouze and Fremy (Cours de Chémie Générale, vol. 3, page 359) may be interesting in this connexion.

By comparing the table of my analyses of sugars (page 528) with the results obtained by Pelouze and Fremy (page 530) it will be seen how well the analyses of sorghum and imphee sugars agree with those performed upon the raw sugars of the sugar-cane. In Pelouze and Fremy’s analyses, white New Orleans sugar was taken as the standard, and placed at 100 per cent. In my analyses white refined sugar was made the standard of comparison. In the table on page 528 the first column of percentages indicates the "uncrystallizable sugar” obtained by means of Fehling’s copper test solution. I have labored under the difficulty of not being able to obtain pure grape sugar for determining the strength of the test solution. The sulphate of copper employed in making the solution was twice crystallized, and then analyzed te determine its purity, by taking two specimens from different parts of the bottle. These analyses gave exactly the same results, and a difference of only 0.09 per cent. oxide of copper when compared with the theoretical percentage. This would involve an error of only 0.001 per cent. of sugar, by operating with-ten grammes of saccharine substances and ten cubic centimetres of the Fehling solution.

It will be seen, by the table upon page 526, that the specimens of sirup generally contain a larger proportion of cane sugar than uncrystallizable sugar.  This cane sugar is held in solution by combination with the salts natural to the juices of the cane, by the viscous character of the molasses, (which in all molasses impedes a free motion of the molecules of cane sugar seeking crystallization,) and by the presence of gums and other impurities.  Doubtless a portion of this cane sugar could be extracted from the molasses. Professor McCullough obtained, in the research before cited, the following results of the optical analyses of the molasses of the sugar-cane:

My analysis (No. 19) of New Orleans molasses yields 25.41 per cent. of uncrystallizable sugar, 40.06 of cane sugar, and 34.53 of water, which agrees with the analysis by outliers. The sirup from sorghum and imphee bears, as may be seen from the analyses, a very strong resemblance to that from the sugar-cane. The peculiar taste or flavor of the sirup called “sorghum taste" is due to imperfect methods of purification during the manufacture, and may be chiefly obviated by proper management.

By the sorghum mean we do not get much more than ten per cent. of sugar in the juice, of which the cane sugar is to the uncrystallizable sugar as 2 to 3.  The first mean of the imphee analysis shows about the same actual percentage of cane sugar, but proportionally more.  I do not think this mean gives as fair a representation of imphee juice asethe second mean, in calculating which analyses Nos. 4 and 4 bis have been omitted. These analyses, showing a large percentage of uncrystallizable sugar and no cane sugar whatever, have a marked influence upon the mean. In the second mean there is about ten per cent. of total sugar, of which the cane sugar is to the uncrystallizable sugar in the proportion of 2 to 1, (more correctly 2 to 1.17.)

It follows, from the experiments thus quoted and reported, that the largest proportion of cane sugar to uncrystallizable sugar is afforded by the juice analyzed by Lawrence Smith, to wit, as 10 to 2. My average results fall far below this; yet if the analyses of my best canes are taken, their juice will compare favorably with that of the analysis of Smith. For example, by the analyses numbered 8, 10, 11, for every 10 parts of cane sugar found, we have respectively 2.1, 1.8, and 1.8 per cents. of uncrystallizable sugar. It is remarkable that in analyses 10 and 11, the juices differing so much in actual saccharine richness should contain the same relative proportion of cane sugar to uncrystallizable sugar. When my mean results are compared with the results afforded by the practical experiment of Mr. Lovering, who grew the sorghum, analyzed its juice, and converted the same into cane sugar and molasses, it appears that my mean of sorghum analyses gives very nearly the same proportion of cane sugar to uncrystallizable sugar, and that my imphee mean gives a larger proportion of cane sugar.  I think that my analyses and their means will give a moderately accurate reflection of the present state of the sorghum and imphee culture in our country.

There are, doubtless, finer canes grown than I have examined, and richer, both in sirup-making quality and in the proportion of cane sugar present; but the analyses probably represent the present condition of the cane as planted.

The country suffers from the deterioration of the seed by hybridization, in the first place. Secondly, we have to learn by practical experiments of planting, (interpreted by chemical analyses,) the best plant to adopt from the sorghum and the fifteen different varieties of the imphee. Lastly, having the plant, we must learn the best soil and mode of cultivation to produce the purest juice and the richest in cane sugar. From present knowledge no certain information can be given as to the relative merits of sorghum and imphee, or as to the soil best calculated for the plant. Among the many practical men who have visited the Department while these experiments were in progress, there is much difference of opinion upon both of these points.  It appears to be the fact, however, from the analyses, that the imphee contains the largest proportion of cane or crystallizable sugar. The analyses of the ash of the plant shows that a light sandy calcareous soil is best adapted to the plant, which is confirmed by the experience of most farmers.

In all sugar-making plants, the heat and light of the sun play a very important part in the formation of the sugar. The beneficial influence of a favorable soil might therefore be overcome by unfavorable conditions as regards the sun, as the presence of certain salts interferes very much with the crystallization of sugar. Any soil or culture increasing the proportion of such salts in the juice is prejudicial. Avequin asserts for the ordinary sugar-cane, that the larger the percentage of sugar in the juice the smaller is found to be the percentage of the above-mentioned salts.

Time and space in the report are insufficient for more than a mere enumeration of those uses of the sorghum and imphee which are established upon a sound scientific basis. With regard to the value of these plants as forage crops, the reader may be referred to the practical results already given in the Agricultural Reports of the government. It appears that the seed of the plant as an article of food is coming into more general favor than hitherto:  W. F. Breck, of Grove City, Franklin county, Ohio, furnished to the State Sorgho Convention of January 6th, flour, bread, rusk, doughnuts, and cake.  The latter were sweetened with the sorgho sirup, and are said to have been very palatable.  The flour was of a purplish color, from imperfect hulling of the seed. The alcoholization of the sorghum is a fact well established, and from this the vinegar making quality of the material follows as a natural consequence. Both alcohol and vinegar of a good quality have been made in the laboratory.

A specimen of sorghum wine, made by a process patented by the Rev. Mr. A. Myers, has been presented for analysis. is wine has the aroma of sherry, and is of acidulous taste. Several methods are given in Olcott’s works on the sorghum and imphee for the manufacture of a wine from this plant. The fibres of the plant would, doubtless, make an article of paper when treated according to the method of Welsbach.

The plant is also susceptible of affording a red dye, which may, by the usual tin mordants, be applied to fabrics of silk and wool. The following is the method of preparing it given by A. Winters—(Liebig’s Jahresbericht, 1859, page 754.) The pressed canes are left to ferment in heaps until the color changes to a red or reddish brown. They are then cut up, dried, and washed.  The color is extracted by a weak lye of caustic potash.  By neutralizing the alkaline solution by a weak solution of oil of vitriol [sulfuric acid -ASC], the color falls in the form of red flakes, which are easily soluble in alcohol, alkalies, and diluted acids.

Johnston (Chemistry of Common Life, page 209) gives the following schedule of the loss of sugar in the practice of the West India islands, compiled from the results of several observers.

The improvements in the machinery and chemical -process of sugar have enabled the attainment of more favorable results than the above, both in the West India islands and in the United States. These improvements have been, for the most part, borrowed from the beet-sugar manufacture of Europe, which is a model of chemical and mechanical skill.  In the earlier period of the beet-root sugar manufacture, from six to seven per cent. of raw sugar and from two to three per cent. of molasses were obtained from the 10-10½ per cent. of saccharine matter in the root. At the present time from seven to eight (and even more) per cent. of sugar are obtained, of which—
   From three to five per cent. are best sugar.
   From two to four per cent. are second quality.
   From one to two per cent. are molasses.

1. Extraction of the juice
2. Its defecation or clarification
3. Filtration through animal charcoal
4. The evaporation by boiling the filtered juice
5. Second filtration through animal charcoal
6. Boiling down the juice to the point of crystallization

Before entering upon the explanation of the chemistry of the process, it will be necessary to inquire into the nature of the vegetable juices under treatment.

This juice contains, first, water; second, cane sugar; third, cellular matter from the veg table cells; fourth, albuminous (nitrogenous) matter of several kinds, as follows: (a) pure vegetable albumen, coagulable by heat; (b) a matter becoming successively red, brown, and black by the oxidation of the air, (this substance is contained only in certain cells of the beet;) (c) another substance containing nitrogen and resembling gelatine, and which may be precipitated by lime; (d) several other nitrogenous bodies the nature of which is not yet well known: these nitrogenous substances decompose with the greatest case, having a tendency to convert the cane sugar to grape sugar, and also to yield products of decomposition which hinder crystallization; fifth, pectine, a substance not containing nitrogen, which, under certain circumstances, takes the form of jelly; sixth, gummy matter; seventh, fatty matter; eighth, coloring matters, odorous and aromatic; ninth, mineral salts; tenth, free acid.  In beet-root that has sprouted, the acid reaction of the juice is stronger, and in such roots some of the cane sugar has been converted into grape sugar.

The sugar-cane contains from two to three times as much woody fibre as the beet; the juice is, however, very much purer, being generally a pure solution of cane sugar in water, with traces of mineral salts, albumen, an nitrogenous matter, coloring matters, &c. The nature of the ingredients is very similar to that described for the beet-root; small as the deleterious matters are in comparison with the juice of the beet, they are abundant enough in quantity to bring about all the injurious cffects of fermentation, formation of grape sugar, &c., during the manufacture.

This juice being new, has been much less studied than that of the beet or cane, and now offers a rich field for investigation as to the proportion and nature of the albuminous and gummy matters contained therein. I have noted one experiment in the present investigation showing a very small amount of gum in the defecated juice of one specimen. The probability is that we shall find matters of the same nature as are found in the beet and cane juice, though varying in amount, (and even in certain instances in kind,) according to seed, soil, cultivation, and climate or season.

The success of the beet sugar turns upon the agricultural treatment of the vegetable. It is easier, by a proper course of agriculture, to keep substances injurious to the manufacture of crystallized sugar out of the juice, than when once present to take them out by the manufacture. In this case a loss of sugar is always involved. The sorghum and imphee juices are much purer for sugar manufacture than beet juice; their molasses is as valuable as sugar-cane molasses, (which is a subject of popular use in this country,) while the beet sugar molasses, on account of its bad taste, cannot be eaten, and is used only for the manufacture of alcohol.

The problem of sorghum sugar at this period presents more hope of solution than did that of beet sugar in the beginning of that industry; but for success, those working upon it must take account of the chemical nature of the juice.  This juice differs from sugar-cane juice in the important particular that a portion of its sugar is in the condition of grape or fruit sugar. In estimating the value of such juice, we should be governed by the percentage of cane sugar in it; for not only can no crystals be obtained from the uncrystallizable sugar, but the products of decomposition of the fruit or grape sugar by lime, heat, or fermentation, afford obstacles to the formation of the crystals of cane sugar.

There are generally present in saccharine juices: water, cane sugar, mineral salts, gum, albuminous and other nitrogenized bodies, together with free acid, or acid salts. In sorghum and imphee juice there is, in addition to the above, fruit or grape sugar. The nitrogenized ingredients and acid of the cane, with the aid of the oxygen of the air, have a tendency, to introduce fermentation, which converts cane sugar to uncrystallizable sugar, besides adding other substances inimical to crystallization.

1. In pressing the juice, therefore, methods must be adopted which perform the work quickly, and the juice should be immediately subjected to the next process, which is—
2. Defecation or clarification.—Several modes have been adopted or proposed at different, times for effecting defecation; that usually employed is lime. The temperature of the juice is raised, milk of lime (whitewash) is added until the reaction is faintly alkaline to litmus paper, and the juice is then boiled for a short time. The heat is then shut off, when clarification rapidly takes place.  A thick green scum rests on the top of the pan, while heavier matters sink to the bottom. This treatment separates all matters capable of precipitation by lime at the boiling temperature. The lime protects the cane sugar, but decomposes a portion of the uncrystallizable sugar if it be present. Avequin found the scum of the striped sugar-cane of Louisiana, arising from this treatment, to have the following composition:

This treatment does not remove all of the nitrogenized matters so injurious to crystallization, all of the gum, nor all of the salts.

3. The juice is then (by the improved process) filtered through animal charcoal. This removes a portion of the lime, all of the coloring matters, and certain of the salts, without materially lessening the amount of sugar. Of course all of the solid matters in suspension are removed by the filter.

4. The juice is then again subjected to a boiling temperature, care being taken that enough lime is present to react faintly alkaline. The water is, of course, driven off and the lime acts upon the nitrogenized substances at the boiling temperature 50 as to decompose them, which fact is proved by the ammonia given off at this stage of the process. Other substances are at the same time separated, as the scum, which is removed. It is very important to observe that when grape sugar is present the lime decomposes it, and that this action is stronger the higher the temperature of the boiling liquid. Brown compound of lime with the products of decomposition of the grape sugar are thus formed. I believe that this is the source of the difficulty which farmers have had with the sorghum juice, even when lime has been employed for defecation. The juices operated upon have been rich in grape sugar. If no lime has been used, the nitrogenized substances are not sufficiently separated; while if lime has been used, it has acted upon the grape sugar to produce an abundance of deleterious substances. In cither case there are present at the close of the process substances which stand in the way of crystallization. The best remedy consists in obtaining a cane which produces a juice as free from grape sugar as possible; but at all events care must be taken during the manufacture that the grape sugar shall not be materially increased and the deleterious substances should be as much as possible removed by the use of animal charcoal.

5. The juice must be freed from all matter capable of being removed by animal charcoal, at some point between the evaporation and crystallization.  This point is fixed by the degree of concentration which the sirup must have to permit it to flow freely through the charcoal filters. The limit lies between 20° Beaume, (specific gravity 1.16,) as usual in the beet sugar-factories of Germany, and 33° Beaume, (specific gravity 1.295,) which is the practice in France. The second filtration through animal charcoal removes coloring matter, a large portion of the lime, nitrogenized matters, and small quantities of certain salts. It leaves on the juice some organic matter (gum ?) and certain mineral salts. The juice is not subjected to any further purification, but is rapidly boiled down to the point of crystallization.

6. Boiling down.—The temperature of the sirup at the commencement of this part of the process is 220½° Fahrenheit, and at the close 266° Fahrenheit.  Since the higher the temperature of the boiling sugar the more rapid is the formation of substances injurious to crystallization, according to the improved sugar process, this boiling is effected in vacuum pans, in which the sirup boils at a very low temperature.  The time when the boiling shall cease is determined by the temperature, or by certain tests which sugar boilers have discovered.  These are: (a) The string tests, which consists in rubbing a portion of the sirup between the fingers and thumb and drawing out the sirup between them. The thread must attain a certain length without breaking, and the separated parts must stick together uniformly. A moderate thread corresponds to 78 per cent. sugar, and boiling point of 226° Fahrenheit. (b) The bubble test consists in dipping a perforated ladle in the sirup, allowing the excess to run off, and then blowing forcibly through the holes, by which bubbles, separating in the form of air balloons, are produced. A well-defined bubble test corresponds to 86 per cent, of sugar, and a boiling point of 248° Fahrenheit. (c) In the water test, a drop of sirup is suffered to fall and cool in cold water. It ought to flatten by its own weight, and not adhere to the fingers. When the sirup has been boiled down to the proper consistency, it is removed and placed in coolers, the contents of which are stirred several times. When the temperature has fallen to from 180° to 185° Fahrenheit, the sirup (s removed to conical moulds having apertures at the bottom, which are at first closed and then opened so as to permit the molasses to drain from the crystallized sugar. These moulds are kept in a warm room to facilitate the draining, which takes place from beet sugar in twelve or fourteen days. The sugar may be further purified from molasses by the process of claying. This is performed by mixing clay with water, and pouring it on the sugar in the mould. The water from the clay becomes saturated with sugar aud drips through the mass of crystals, washing out the greater portion of the molasses. Liquoring is an improvement upon the claying process. It consists in pouring upon the sugar in the mould a saturated solution of refined sugar. The effect is the same in washing out the molasses. Knapp, in describing the beet sugar manufacture, states that “a mould containing from thirty to forty pounds of sugar sirup yields, after liquoring, a solution of sugar at the expiration of ten or twelve days, or when clay is used, in twenty or thirty days, from twelve to fifteen pounds of lump sugar.”  I have thus set forth, in general terms, the theory of the sugar manufacture from cane and beets, The sorghum sugar manufacture will require at least as much skill and care as that of the sugar-cane, and probably as much as that of the beet, in order to make it a profitable investment for general use. That these principles are applicable to the new canes is abundantly established by the experiments of that able sugar refiner and scientific man, Joseph S. Lovering. The present high price of sugar enables this skillful treatment of the new canes to be tested practically by men in the west who are investing money in the erection of suitable sugar-houses, containing the proper machinery for manufacturing pure sugar.

Those who treat the juice of the cane upon a small scale, whether for sugar or sirup, will meet with greater success the more closely they adhere to the principles laid down above. The greatest difficulty in their way, as the analyses of the sorghum and imphee canes show very distinctly, arises from the uncertain composition of the juices obtained from the different canes which are grown.  Hence we find men who are very successful with cerain kinds of cane. These canes, as far as I have been able to test them, do really contain a larger proportion of cane sugar over grape sugar. The great desideratum at present is the best cane. Experiments to be tried by the farmers, in connexion with the analyses of the cane thus grown, will establish this desirable point.  In these agricultural experiments care must be taken to prevent hybridization, so that the seed produced will yield a plant like that analyzed.

Farmers who care o make sirup only may use those evaporators which enable a rapid evaporation of the juice combined with an effective separation of the impurities by skimming.  If this evaporation can be preceded by a defecation with lime and heat, in a separate vessel, so much the better; but such defecation shoulil be followed at some time subsequently during the evaporation by a filtration through animal charcoal.  If the juice is rich in grape sugar and weak in cane sugar, the addition of lime will give a poorer sirup than to omit it.  Careful boiling and skimming is then the best plan to adopt.  If, on the other hand, the juice is rich in cane sugar and poor in grape sugar, a defecation by lime and once (or better twice, as directed above) filtration through animal charcoal cannot fail to reward the farmer with a crop of crystals and with good sirup.

In closing my report, I would remark that the collection in the laboratory of such soils, manures, plants, wines, &c., &c., the analyses of which might prove of general interest to farmers, is gradually increasing, and that I have arranged plans for such analyses.