bread from the pure yeast had a volume of 2,820 cc, while the corn-starch yeast mixture bread had a volume of 2,650 cc.

As in the action of yeast on sugar solutions, the actual baking tests show that the carbon dioxid value is always greater in the case of pure yeast. By comparison it will be found, however, that the average percentage difference in the size of the loaves is less than the average difference in loss of weight of the sugar solutions for the same periods. This is due to the fact that in the case of the bread it is only the final volumes that are compared, whereas to make the results comparable with those obtained by the action of yeast on sugar solutions it would be necessary to determine the difference in volume (for 2 grams of yeast) between the freshly mixed bread and the final volume of the loaf. There is much work to be done before the action of starch in yeast will be known in all its details. The writer feels, however, that the results here given are sufficient to justify the statement that starch in compressed yeast is an adulteration. The advantage to the manufacturer is easily seen when we consider that he sells starch which costs less than 3 cents per pound at the price of yeast which costs 15 cents per pound. A standard for compressed yeast that will exclude the use of added starch is therefore most desirable. Next to the quality of the flour the quality of the yeast is of prime importance to the 70,000,000 people of this country in the preparation of their bread.

TABLE I.-Average loss in weight of sugar solution containing pure yeast and yeast-starch mixtures, September 19 to October 2, 1907.

TABLE II.-Carbon dioxid gas produced in sugar solutions containing yeaststarch mixtures as compared with those containing pure yeast, rated at 100.

Vice-President Snyder took the chair at this point and Mr. J. P. Street delivered the annual presidential address.

PRESIDENT'S ADDRESS.

By J. P. STREET.

Gentlemen of the Association: An unfortunate unwritten law, supported by the custom of many years, demands an address from your presiding officer. My 23 predecessors have covered the ground so well, and have appreciated the merits and the failings of this association so thoroughly, that there is but little left for me to do save to repeat their congratulations and emphasize their warnings.

That the original object of this association was to secure uniform and accurate methods for the analysis of fertilizers is known to you all. Likewise you are all familiar with our steady growth, until now we include within the province of our study and control practically all materials connected with agricultural industry. This widening of the association's activities has limited in some degree the interest of the members in its work as a whole. This is an inevitable result of our expansion, and, deplorable as it is from certain points of view, it could not be expected that either time, inclination, or immediate interest would lead all the members to take part in all the work. This is no reason, however. why every member should not take part in some of the cooperative work each year, and by his careful work help in the solution of the numerous problems that still confront the agricultural chemist. In the association's earlier days it was the custom for practically every institution represented in its membership to share in the cooperative work, and this was easily possible when fertilizers alone were the subject of study. It was also the custom then that this work should be performed by the experienced men of the staff, so that when the results were presented to the referee for comparison and study they would furnish a reasonable test of the method's accuracy, and not of the capability of the analysts. But in later years this condition to a great extent changed; the official samples all too often were used to check the younger assistants rather than the method itself. This resulted in certain cases in injustice to methods which proved later to be thoroughly dependable, and it would seem that the publication of certain of the comparative results must have had a harmful effect on our standing as an association. It is a matter of deep gratification,

therefore, to observe that as a result of recent agitation of this subject the pendulum is swinging back, and we find that a large proportion of our association work is again intrusted to those best qualified to handle it. While the privilege of assisting in our work should be denied to none of our members, still greater efficiency would be secured if even wider latitude were permitted the referees in the selection of their associates. These associates should be not only skilled manipulators, but should have given particular attention to the subject under investigation. While general cooperation, as I shall point out later, is most desirable, it would be far better for the skilled chemist to decline to take part in an investigation than to intrust the details to an inexperienced assistant. Surely there is no member of this association who is not expert in at least one branch of agricultural analysis and whose work would not be of great value if properly directed.

As a matter of interest, I have tabulated the work of the past ten years, to determine the amount of cooperation of the various State laboratories. In preparing this summary I have naturally left entirely out of consideration the Bureau of Chemistry, and it is only just that attention should be called to the valuable work done by the Bureau each year in the study of our methods. With five referees and eight associates included in its organization this year, besides doubtless many others assisting in the work of other referees, the interest of its controlling officers in this association is manifest, and we are under deep obligation to them for the liberal policy which they have fathered. When we consider the results of my tabulation, and learn what the attitude of the various State institutions has been toward this association, a different story is told. I find that two of the States took part in the work in each of the ten years, thirteen in from seven to nine years, fourteen in from four to six years, three in from one to three years, and four States gave no assistance whatever. Four States, three of them distinctively agricultural, showed not the slightest practical interest in the work of the association during a period of ten years. By further subdividing the time under consideration into two periods of five years each, it is seen that there has been an increased activity in all the groups of States during the past five years, with the exception of the Middle West, this activity being specially marked in the Central and Pacific States. The encouragement furnished by this second classification is somewhat diminished, however, by the fact that from 1901 to 1906, inclusive, six States cooperated but twice, thirteen but once, and nine not at all. Do not these facts, which can be easily verified by a study of our reports, show either that there is a lack of sympathy with the association and its work on the part of those in control of many of our experiment stations, or that there is a willingness to cast the burden of this work on others, and enjoy the fruits of their labors. Efficient and accurate methods of analysis are the groundwork of all agricultural research, and any station which fails to aid in their development and application shirks a manifest duty and plays the rôle of a parasite on this association.

There is another subject which I feel many of our members do not approach with a keen sense of the duty involved. In 1896, when acting as referee on nitrogen, I made a recommendation, which after much discussion by the committee was distorted to read as follows: Resolved, That it is the sense of this association that the forms of the nitrogen in commercial fertilizers should be reported, where it is possible to do so." The clause" where it is possible to do so" cast the resolution, as far as its effect was concerned, into

"A limbo large and broad, since called

The paradise of fools."

In 1902, as chairman of Committee A on Recommendations, I was able to rescue the matter in a measure from its undeserved oblivion by urging the association to take a somewhat more decided stand by the adoption of the following resolution: "That it be earnestly urged that, in reporting the analyses of complete fertilizers, the amounts of nitrogen existing in the form of nitrates, ammonia salts, and organic nitrogen be specifically stated." And there the matter rests to-day.

In spite of this specific recommendation from what should be considered the court of last resort in matters pertaining to agricultural chemistry, what has been the attitude of those having charge of the thirty-one different fertilizer controls? Five controls report the three forms of nitrogen, three report nitrogen soluble and insoluble in water, or total nitrogen and nitrates, and one reports total and available nitrogen; twenty-two report only total nitrogen. Fifteen of these delinquents report phosphoric acid in three forms, and four of them separate the potash, as from chlorid and sulphates. Is not this a glaring inconsistency? The form of the nitrogen, the most important and most expensive ingredient of the fertilizer, is absolutely ignored by 70 per cent of the inspection officials, while insoluble phosphoric acid is carefully determined by most of them by a method whose accuracy is universally discredited. Surely there is no excuse for this careless, I will not say ignorant, attitude. Excellent, exact, and rapid methods for the determination of nitrates and ammonia salts are at the disposal of every inspection official, and the resulting benefits would more than compensate for the slight additional time consumed.

The only excuse that I have ever heard offered for failure to make these determinations was lack of time to do more than the law required. I can not believe this an honest excuse. Is it not time that the fertilizer appropriation or the income from fertilizer fees should cease to be considered as a financial aid to carry on more interesting investigations in other lines of work? Is it not our official duty, not simply to make a perfunctory examination to satisfy the requirements of the law, but also to impart to the consumer all the information possible from our present methods of analysis as to the sources of the materials used in compounding the mixtures offered to him for purchase? And what has been the result of this indifference, this neglect of duty, this shirking of responsibility? The fertilizer manufacturer has watched us, gentlemen; he has learned the weak points in our armor, and he has always kept a decade in advance of us. The commercial instinct is not dormant in his heart. The high price of nitrogenous fertilizing materials has tempted him to use any and all materials, often inert and valueless, for he knew that with few exceptions the inspection officials would not differentiate these from higher grade materials, but would by their analysis classify them with the best and most available forms, and give them a correspondingly high commercial valuation. Is it any wonder, then, and are we entirely blameless, that the use of these inert materials is continually increasing, until now we are forced in defense of the interests confided to our care to attempt some laboratory method for distinguishing available and inert organic nitrogen? For several years the association has been studying methods with this end in view, but the progress has been slow and the cooperative work has been slight. It is a subject which merits the earnest thought and the patient study of every fertilizer control official, and without this concentrated effort the problem will long remain unsolved. Our obligation to the manufacturer who continues to use only high-grade materials in his fertilizers is as well defined as is our duty toward our constituents, the agricultural public, who

have a right to know the nature of the materials offered them as possessing high fertilizing value.

A review of the history of this association clearly indicates that it is a conservative organization. This conservatism has always been an element of strength, and the wisdom of our attitude toward the adoption of new methods can not be questioned. When we have been confronted by new agricultural problems, however, it must be confessed that in some cases at least our conservatism has degenerated into a sort of artful dodging. Two queries well illustrate my contention: How shall we measure the availability of basic slag? And is there such a thing as "available" potash as distinguished from watersoluble potash? Our attitude toward these problems is known by you all. Basic slag has been the shuttlecock of this association for a number of years, and, as far as any official pronunciamento as to its status and methods to determine its worth is concerned, we are just about where we started. The importance of this material as a phosphatic fertilizer will increase with the years, and the time is not far distant when we shall be obliged to decide the question by some other method than skillful side stepping. The question of "available" potash is being forced on our attention by the manufacturers, who make the twofold claim that our present methods do not credit them with all the watersoluble potash they supply in their mixtures and do not recognize the agricultural value of certain forms of potash which are insoluble in water. The work of our referee on potash for the past two years seems to support the contention that not all the water-soluble potash added appears in the analysis when made by the official methods. It is true that we may have serious doubts as to the wisdom of adopting any modification of the method which permits the use of a solvent, which might bring inert potash into solution, and I believe the association made no mistake. in rejecting the recommendation of the referee for the adoption of this modification. Nevertheless the manufacturer, who surely is entitled to justice and protection quite as much as the consumer, makes a claim which our own work seems to justify, and the obligation rests upon us to seek some modification of our methods which will remove from them even the slightest stigma of injustice. And the same holds true with the question of "available potash." We are not in a position to affirm or deny the manufacturer's claim that the potash which he adds in an organic or mineral form, and which is not soluble in water, possesses an agricultural value approximately the same as the water-soluble form. The claim, however, demands our consideration and is worthy of our careful study.

We must not deceive ourselves into the comforting belief that the labors of this association are at an end. In spite of the remarkable progress made by our very efficient referees in the last few years in perfecting our methods for food analysis, every food chemist realizes the gaps which still exist in these methods and the new problems that are constantly being presented. The analysis of drugs is almost an unexplored field. Your attention has just been called to some of the unsolved problems in fertilizer analysis. A brief glance at the subject of cattle foods will show that here is another unexhausted territory. It is hardly necessary to call attention to the fact that no one of the ordinary determinations in cattle foods, with the possible exception of ash, is scientifically accurate. These inaccuracies are, however, in themselves of minor importance from a feeding standpoint, except that the algebraic sum of all the errors involved, by our present method of calculation by difference, falls upon the "nitrogen-free extract." Not only is the aggregate percentage conceded to "nitrogen-free extract" usually inexact, but it is manifestly unscientific to group together under one heading such dissimilar substances as