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In regard to the system of diffusion practiced at the Rio Grande sta. tion, and described in Bulletin 18, further experience only leads me to emphasize what was said in that bulletin, viz:
The defects of the system were both mechanical and chemical.
The mechanical difficulty is the same as that which attends all methods of diffusion in which the cane chips are moved instead of the diffusion liquors. From a mechanical point of view it is far easier and more economical to move a liquid in a series of vessels than a mass of chips. in the Hughes system the whole mass of chips under going diffusion, together with adhering liquor, and baskets and suspending apparatusare listed vertically a distance of several feet, varying with the depth of the diffusion, tanks, every few minutes. The mechanical energy required to do this work is enormous, and with large batteries the process would prove almost impossible.
The truth of this view will be further illustrated in the report of the Douglass Sugar Company. For very small batteries working only a few tons a day this system might possibly be employed, but I doubt even then if it could be economically worked. This opinion of mine, as will be seen, is at total variance with that expressed by Mr. Hughes, and those who propose to become practically interested in the matter will have to decide upon the merits of the two systems of diffusion after a personal investigation.
Mr. Hubert Edson, who has had two years' experience with the open system of diffusion, made the following statements relating thereto in the Lousiana Planter and Sugar Manufacturer of December 1, 1888. Ilis report refers to the battery used at Douglass, Kans., during the season of 1888:
The battery was built from plans secured directly from Mr. Hughes, and with one or two slight changes was worked throughout the season. The main battery consisted of ten cells, open at the top to admit the baskets in which the chips were placed for diffusion. These baskets, made of strong boiler-iron, were attached to the arms of a crane, which was raised, rotated, and loweral till the requisite number of inmersions was obtained. Besides these ten cells there was an extra one of the same dimensions placed just outside and within reach of the arms from the large crape. This arrangement was intended to secure a dense diffusion juice, allowing, as the diffusion progressed, the heaviest juice from two of the cells of the main battery to be drawn into the outside cell, and which there received two baskets of fresh chips before being emptied.
This manner of operating the battery will, it is claimed by the inventor, give a juice almost as dense as a corresponding mill juice. In my opinion, however, no greater advantage is secured by the e'eventh cell being outside the main battery than by the same number arranged in regular order. Certainly, at Donglass, the results claimed by the inventor were not even approximated. The ontside cell also entailed an extra amount of labor iu transferring the basket from the small crane, to which it was attached during its immersion, to the large crane of the main battery.
So much for the manner of working the battery. Now for the things that are of actual value to the sugar planters, the results obtained, and the expenses incident to such results.
Machinery of any kind to be effective should require a minimum of human labor. Let us see how the Hughes battery compares with the ordinary form. At Douglass the battery was designed to work 100 tons of cane daily, and to do this at least cight men were necessary to shift the baskets to their different places. Half of this number wonld run a close battery and fiul the work easier, since they would have no baskets weighing 1,000 pounds each to handle.
Besides this manual labor the whole ten baskets had to be raised every timo one was filled or emptied. A large lıydraulic pump is used for this work and ot' itself requires more power than is necessary to run a battery of closed cells. This extra power anıl labor would not necessarily condemn the apparatus if such superior results were obtained as to overcome the expense. But instead of this, exactly the reverse was accomplished. Not much better extraction was secured than is obtained by the ordinary cane-mill of Louisiana, and this only with a dilution of nearly 50 per cent., causing au extra expense of no small aniount for evaporation. Then, also, the quality of the juice obtained was extremely poor. The almost constant exposure to the air and especially in irou vessels blackened it to such a degree that no good sugars could be made from it. Clarification was nearly impossible with any of the ordinary re-agents in the sugar-house. This was extremely unfortunate in Kansas, as the greatest profits are inade on material sold to the home market.
Full reports of the chemical work at Rio Grande are contained in Bulletin 51, New Jersey Experiment Station.
EXPERIMENTS AT KENNER, LA.
As has been mentioned before, Prof. W. C. Stubbs was placed in charge of the experiments which were arranged for in connection with the Louisiana sugar experiment station at Kenner and the stations at Baton Rouge and Calhoun. For two previous seasons Professor Stubbs had made extensive experiments with sorghun, wbich are fully reported in the bulletins of the Louisiana experiment station and in Bulletin No. 18 of this division. A study of the analytical data of the three years' work in Louisiana shows in an emphatic way the peculiarities of sorghum wiich have rendered so difficult the successful inauguration of sugarmaking from that plant. The great variations in the content of sucrose in the juices of the plant, its susceptibility to injury by storms and other unforeseen causes, are strikingly set forth in the analytical figures which follow. In my opinion the production of a variety of sorghum-cane suitable to the soil and climate of the sugar lands of Louisiana will be a work of no small difficulty. From the results of the work already done, and especially during the last year, an account of which is contained in the appender report of Professor Stubbs, it is clearly seen that a season wbich has produced a sugar cane very rich in sucrose in the State of Louisiana has produced a sorghum crop which is absolutely worthless for sugar-making for cominercial purposes. Another point illustrated by the report is bronglat out in the reference to the past work of the station, in which, although a cane was produced whose juice was reasonably rich in sucrose, its practical working in the sugar factory was found most difficult. In the report this is ascribed to the presence of large quantities of dextrine or dextrine like bodies supposed to be de. rived from the starch originally present in the juice. It is the opinion of Professor Stubbs that starch and sucrose are developed in the sor'ghum pari prosent. In this case it would be found that the direct polari zation of a sorglium juice rich in sugar would show apparently a much higher content of sucrose than was actually present, since dextrine and its allierl boilies are much more strongly dextro gyratory than sucrose. The points developed by the experiments may be summarized as follows:
(1) Sorghum cave develops sometimes in Louisiana a juice containing a very high percentage of sucrose, but combined with other bodies wbich render its separation from the juice difficult.
(2) The occurrence of a wet summer attended by the severe winil. storins which are so common in that locality prevent the development of a high sucrose content in the growing sorglum.
(3) The possible utilization of sugar machinery for a longer manufacturing seasou is one of the chief inducements in the sugar cane regions for the cultivation of sorghum as a sugar-producing plant.
(4) Delay in working the cane after cutting is not as dangerous as has been supposed.
It will be understood that these are conclusions which I have drawn from reading Professor Stubbs's report, and are not formulated in the above manner by himself.
The results of attempts to grow sorghum for sugar-making purposes on the low sugar-lauds of Louisiana, in my opinion, are not highly enconraging to the belief that these lands and their climate are the best suited in the United States for the production of sorghum, as Professor Stubbs says. On the other hand, I beliere there are few localities in the United States, where sorghum grows at all, in which a better crop for sugar-making purposes can not be produced. Experience has shown that the dry climate of southern and western Kansas produces the most uniform crop of sorghum for sugar making purposes, while the data of Pro'essor Stubbs, which follow, sliow that the Louisiana product, for the present year at least, is about the poorest on record. One point, how. ever, should be borne in mind, viz, that the course of experiment pursued by the Louisiana experiment station is the one which is best suited for the rapid development of every possibility of sorghum culture in that State. The experimental trials which are made with sorghum will show both its weak and strong points, and in the wide variation whiclı the plant shows there will doubtless be some variety produced or found which will be best suited to the peculiar conditions which obtain in that locality. The soil and climatic conditions of the northern part of the State, where cotton is now grown, will probably be found better suited to the production of sorghum than those of the present sigar-producing localities. I feel quite sure that the expectation expressed by Professor Stubbs of being able to realize under certain conilitions as much as 120 to 125 pounds of sugar from sorghum cane may be fully met wier favorable circumstances; but it would still remain to be demonstrated that this yield could be reasonably expected from year to year, or even occasionally, on a large scale. The subsequent experiments which are promised by Professor Stubbs at the Louisiana station will doubtless set at rest, in a few years, all these questions, and demonstrate to the sugar makers of Louisiana just what can be expected from sorghum as an adjunct to their great industry.
EXPERIMENTS AT CONWAY SPRINGS.
In the reports of Messrs. Deming and von Schweinitz which follow, together with the analytical tables, much interesting information may be found in regard to the sorghum sugar industry in Kansas.
The successful continuation of the work at Fort Scott has encourged the be. lief in the possibility of a speedy establishment of a sorghum sugar industry in Kansas on a large scale. The unfortunate financial outcome of the work at Conway Springs shows that much is yet to be learned by those entering upon this ivdustry before success can be confidently predicted. A discussion of the cbemical data collected at Conway Springs will be found in connection with the analytical tables. It is proper to say here, however, that the sorghum juces of the crop growu at Conway Springs show a higher content of sucrose than any large crop which has ever before been produced in the United States. This higli content of sucrose which appeareil in the crop after the middle of September, as indicated by the analysis of the juices, was continued until the close of the working season in November. The sam: ples of chips taken from the cells of the battery showed in their juices a high content of sucrose uniformly; much higher, in fact, than would be indicated by the output of sugar. One reasou, doubtless, for this was the exceptionally dry season diminishing the content of water in the cane and thus increasing the percentage of sucrose in the juice. This fact, though not established by the determination of the fiber in the
cane, is plainly indicated by two other facts developed by the analyt. ical work, viz, the diminished extraction when using the small mill at the same pressure as the season progressed and the bigli content of total solids in the juices. The output of sugar was evidently diminished by the character of the water used in diffusion, but that would be unable to account for the small yield of crystallizable sugar obtained with juices of the ricbness of those worked. Experiments made by boiling a solution of pure sugar with the water used in diffusion at Conray Springs proved that the presence of a large amount of gypsum did not tend to increase the inversion of sucrose; that it may, however, have interfered with the crystallization of the sucrose is a fact wbich can scarcely be denied. The actual output of sugar at Conway Springs, in my opinion, would have been considerably larger had pure water been employed in the diffusion battery; nevertheless, the important fact remains that the yield of crystallizable sugar was wholly disproportional to the richness of the juices worked, showing that the high ratio of sucrose was not obtained at the expense of the solids not sugar in the juices. In other words, it appears that a cane whose juice is normal in quantity, say about 90 per cent. of the total weight, and having a content of sugar equal to 10 per cent., with total solids at 16 per cent., will yielil fully as much, if not more, sugar than a cane whose juice is abuormal, say not more than 80 per cent. of the total weight, with 12 per cent. of sucrose and 18 or 20 per cent. of total solids. Another impor.
tant fact developed by a study of the data obtained at Conway Springs is the persistence of the sugar content in the juice after the carie was fully ripened. In localities where considerable moisture may be expected in the soil as a result of frequent rains during the manufacturing season it has been noticed that there is a rapid deterioration of the juices, beginning a short time after complete maturation. This has been especially noticed in the experience at the Rio Grande station. It has also been noticed by all careful observers of sorghum grown in ordinary localities. The inspissation of the juices by the natural causes of an extremely dry climate appears to protect the sugar from this destruction. This is a point of the greatest interest to sorghum-growers, to whom the preservation of the sugar in the juice for a reasonable length of time is a matter of the greatest consideration. In the process of diffusion this thickening of the juice entails no loss, although if milling were used for expressing the juice the loss would be a most serious one. The above explanation of the character of the juice at Conway Springs is offered with some degree of hesitation, since I am fully aware of the danger of drawing conclusions in sorghum work from a too limited number of observations.
The manufacturing operations at Conway Springs were greatly hin. dered by faults in the machinery, which could scarcely be avoided when the short time allowed for the manuacture and erection of the same is considered. Justead of taking three months for the erection of a sugar factory, a whole year is none too long a time, and disaster, for at least one year, is certain to attend attempts to erect such machinery in the time allowed at Conway Springs.
What is needed now in the sorg bum-sugar industry is the manufacture of sugar at a rate which will enable the manufacturer to compete with sugar from other parts of the world. A great step in this direction will be secured when the kind of machinery which has been pointed out by the investigations of the Department as necessary to success shall be constructed by skilled machinists and erected by skilled engineers, with time enough at their disposal to finish their work before the manufacturing season begins. Some further remarks on this subject will be made in another place.
From a commercial point of view, the results of the work at Conway Springs are wholly disappointing. To the person, however, who will take pains to inform himself in regard to the conditions which there obtained, many points of encouragement will be found in spite of the financial failure of the first season's work.
EXPERIMENTS AT DOUGLASS, KANS. The practical experiments carried on at Douglass consisted in a thorough trial of the open system of diffusion (the Hughes system) to test its fitness for working on a large scale. For the details of the con