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sugars, starch, gums, pectin bodies, pentosans, lignin, and the various modifications of the hemicelluloses and oxycelluloses, especially when they constitute such a large part of the feed under examination, varying from 26 per cent in cotton-seed meal to 80 per cent in rice. The meaninglessness of this term has been recognized by all, and in recent years much excellent, and in some cases conclusive, work has been done toward the separation and determination of many of these carbohydrate bodies. Recent work of my own in a study of the carbohydrates of dried beet pulp has convinced me that this matter is important not only from an analytical point of view, but also in that its solution would shed much light on many of the problems of animal feeding. The sugars and starches are by common consent rated as the most assimilable forms of the carbohydrates, and yet feeding experiments have shown that beet pulp, which contains these forms in minimum quantities, was more efficacious than hominy meal, a typical starchy feed. Does not this surprising result indicate either that our methods of feed analysis are misleading, or that certain of the carbohydrates generally classed as inferior for feeding purposes are, in certain feeds at least, of superior quality and of high digestibility?

By subjecting beet pulp successively to a series of solvents, as originally suggested by Dragendorff, and further developed by Parsons, Frear, Browne, Sherman, and others, and analyzing the various residues and solutions, I secured some very interesting and suggestive results. Large amounts of araban, galactan, lignin acids, and lignin were found, with smaller quantities of pectin, parapectin, and reducing and invert sugars; while nearly one-quarter, or 16 per cent, of the carbohydrates existed as unidentified hemicelluloses, which were dissolved by dilute sulphuric acid and were present in an incompletely hydrolysed state. It was shown that the galactan was present in three forms; one fraction was soluble in 80 per cent alcohol, one was soluble in cold water, and the balance was hydrolysed by dilute sulphuric acid. The pentosan arabans in this case were even more complex, and varied greatly in their resistance to solvents. Varying portions were soluble in cold water, in dilute acid, in warm water, in diastase solution, and in dilute alkali, and still another portion was removed by chlorination. The chlorination process gave a percentage of cellulose 6.5 per cent lower than the official method, the residue being entirely free of pentosans and proteids, but still containing one-fourth of the original ash.

Time does not permit me to go into further details as to the results of this investigation. My experience with this material, however, leads me to the conclusion that for a rational basis of scientific feeding we must not be content with the determination of the total of any ingredient, but must differentiate its various forms as indicated by their behavior with a series of solvents. The fact that we have in beet pulp apparently at least six different modifications of araban and three of galactan would encourage the assumption that a determination of total araban and total galactan in a feed conveys as little useful information as one of total phosphoric acid in a fertilizer.

On reading the constitution of this association I note that its objects are twofold, not only to secure uniform and accurate methods of analysis, as already mentioned, but also “to afford opportunity for the discussion of matters of interest to agricultural chemists." It would seem that this second and very important object of the association had been to a great extent neglected. We have increased the scope of the association without a corresponding increase in the length of our meeting, with the result that practically all of our time has been occupied in the presentation of reports, too often presented in an undigested form, which because the necessary data are not before us, are unin

telligible to all except the few who have taken part in the work on the particular subject in question. Discussion of the reports has been reduced to a minimum; in fact, it has been discouraged. As a result, our meetings have lost some of their interest, and the benefits resulting from them have somewhat diminished. No member of this association, I am confident, will deny that one of the greatest advantages derived from attendance at these meetings is the opportunity for the exchange of ideas, whereby we learn the experience of others in the lines of work that have presented difficulties to us ourselves. This information we have been forced to obtain outside the formal meetings of the association, and the benefits accruing therefrom have therefore been limited to those whose intimate acquaintance has permitted questions a stranger would not feel at liberty to ask. It would seem that these benefits derived from experience should be open to all our members, and that the proper place for their discussion is the floor of this convention.

It is impossible for us all to take an equal interest in all the ramified work of this association, and a general meeting for papers and discussion might not meet with unqualified success. I would urge, therefore, that one day be devoted entirely to the reading of papers and their discussion, and that for this purpose the convention be divided into three sections covering the same subjects as our present committees on recommendations. All papers to be read in these

sectional meetings should be referred to the proper committee with full power to reject the same, or assign places to them in the programme, which should be sent to all members prior to the convention. I believe in this way, gentlemen, that the interest in our meetings would be greatly intensified, and an immediate as well as lasting benefit conferred upon our members.

The constantly changing personnel of this association is an element of weakness and gives to it a character of impermanency. This fact has been particularly impressed upon me during the past two years in my work with the committee on revision of methods. We were confronted by a great mass of methods couched in as many forms of English as there had been referees, with varying nomenclature and with no fixed or systematic method of treatment. Under the conditions attending the origin of our methods no other result could have been expected. Your committee has attempted, and I trust with a considerable degree of success, to bring order out of this chaos and has rewritten the methods with the idea of clearness and uniformity of statement constantly in mind. And yet all this labor will go for naught and our methods in a few years will return to their previous state of indefiniteness unless our present system is corrected.

The one permanent office in this association has been that of secretary. There seems to be an unwritten law that during his natural life Doctor Wiley shall be our secretary, his occupancy of that office being conditioned only by his good behavior. The benefits accruing to the association by this, its one permanent feature, are undoubted, and any effort to insure further permanency in other departments of the association would seem worthy of encouragement. In order, therefore, to launch the association upon a settled policy in the matter of methods the primal reason for our existence as an association I strongly recommend the appointment of a permanent committee on methods, consisting of nine members, who shall hold office until disqualified by the provisions of the constitution; this committee to consist of three subcommittees corresponding to our present committees A, B, and C. This committee shall receive all reports of referees at least three weeks before the annual meeting of the association, should edit them for presentation to the convention, and after the adoption of new methods or modifications of the old ones, should incorporate

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them in our official methods in harmony with our newly established system of treatment. In this way the policy of the association as regards methods would continue unaltered year after year, and the committees would not labor under the disadvantage, so often evidenced in the past, of unfamiliarity with the work of their predecessors.

One more presidential suggestion, and I am through. Our constitution provides in definite terms who are eligible to membership in this association. Section 2 reads as follows: "Analytical chemists connected with the United States Department of Agriculture, or with any State or National agricultural experiment station or agricultural college, or with any State or National institution or body charged with official control of the materials named in section 1, shall alone be eligible to membership." And later in the same section we read: “All analytical chemists and others interested in the objects of the association may attend its meetings and take part in its discussions, but shall not be entitled to enter motions or vote." It is not entirely clear in my mind just what the words "any State or National" mean. I had supposed that our memberhsip was limited to agricultural chemists in this country, but the above wording, according to my interpretation, might include those connected with agricultural institutions in any State or country. It hardly seems possible that this could have been the meaning of the framers of our constitution, and but for the fact that our Canadian confrères have always enjoyed all the privileges of the association, I would not raise the point at this time. We all appreciate the valuable contributions to our methods from our Canadian friends, and I think no one would deny to them the privileges of membership, and yet I believe we should maintain this as a North American association. I would suggest, therefore, that this ambiguity in the constitution be considered at this meeting by a special committee, and would recommend that the constitution be so amended as to include Canada and Mexico as the only foreign countries entitled to representation.

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The constitution provides that unofficial analytical chemists are not titled to enter motions or vote." Surely the more important duty of acting as referee should also be denied them, and yet they are not specifically barred from this privilege by the constitution. Unofficial chemists have frequently acted as our referees in the past, and in many cases the association has benefited by their labors; and yet, with all respect to these gentlemen, the precedent established is a dangerous one and can not be too speedily corrected. We should heed Virgil's warning: “Timeo Danaos et dona ferentes."

I would not have the members of the association assume from the somewhat critical tone of my remarks that I am unmindful of the excellent work of the past, of the authoritative position the association now occupies in scientific and legal circles, and of the patient, self-denying, self-effacing work of many of our members in advancing agricultural analysis to its present high plane, But self-complacency and self-congratulation are not incentives to determined, progressive action. Much of our work in the past has had to do with the comparatively simple problems of agricultural analysis; the work of the future will demand effort of an even higher grade, based on careful, painstaking, intelligently directed research. Every station owes it to the public to do some work of original investigation. The analytical methods employed are in a sense the tools by which any agricultural chemical investigation is made possible. The perfection of these tools alone makes possible successful investigation with them. It is certainly, then, no unworthy or unimportant work for a station to spend time in the careful study and perfection of methods.

APPOINTMENT OF COMMITTEES.

At the close of the president's address, which was received with marked approval by the association, the following committees were announced:

Committee on resolutions: Messrs. Van Slyke, Hopkins, and Withers. Committee on nominations: Messrs. Hartwell, Bartlett, and Cathcart. Committee on amendments to the constitution: Messrs. Frear, Kilgore, and Lipman.

On motion by Doctor Wiley the recommendations offered in the president's address were referred to the committee on resolutions. The report of the referee on nitrogen was then presented by the secretary as follows:

REPORT ON THE DETERMINATION OF NITROGEN.

By CHARLES L. PENNY, Referee.

The following circular letter, together with samples of corn meal and cottonseed meal, was sent to members of the association:

The referee and associate referee on nitrogen request you to determine the nitrogen and moisture in a sample of corn meal and one of cotton-seed meal sent to you by mail.

It is requested that nitrogen be determined by the Kjeldahl method and also, if convenient, by the soda-lime method or the absolute method. As a comparison of analytical figures is contemplated, with a view to repetition in cases of wide variation from the average, it is hoped that the work may be done promptly.

Please state in reference to the moisture and the Kjeldahl method—

(1) Temperature at which moisture is determined, and also whether in air or hydrogen.

(2) Duplicates of nitrogen separately, not merely the average.

(3) Whether at end of digestion the hot sulphuric acid was quite colorless.

(4) Whether permanganate of potash was used or not; and if used, whether to the point of permanent coloration.

(5) Any other reagents used in the digestion.

(6) The quantity of substance taken for a determination, the amount of sulphuric acid used, and the size of digestion flasks.

(7) The approximate time of digestion and of distillation.

(8) Whether blanks were digested and distilled; and if so, the amount of correction; also whether the distillation was proved to be complete by the collection of a second portion of distillate.

(9) Method of standardizing acid and the indicator used.

It is hoped that all chemists will cooperate in this work, as it is believed that no single determination interests so many as does that of nitrogen, that few are so important, and that unfortunately variations in analytical results have been unreasonably wide.

Address replies to the referee

FEBRUARY 16, 1907.

C. L. PENNY,

Agricultural Experiment Station, Newark, Del.

Fifty-three analysts took part in the work, contributing a valuable collection of opinions and experiments. The generous portion of time and labor given by them shows a deep interest in every attempt at the improvement of our analytical methods. Over 420 separate determinations of nitrogen and about 120 of moisture were made, some according to strictly prescribed methods and others according to methods deviating in several respects from these. The list of analysts participating in this work may be found in the table of moisture

determinations. The samples were taken from a quantity of material thoroughly mixed, bottled, and sealed; it is believed that they were as nearly uniform as they could be made, and fully secured from change in moisture content or other change. The following table shows the percentage of moisture found by the several analysts and the methods pursued by each:

TABLE I.-Results of cooperative work on the determination of moisture in corn meal and cotton-seed meal.

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