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rather strongly provoked. Its fangs are in

tact.

With the aid of two assistants, Mr. Ledieu, who kept the head out of mischief, and Mr. Bunch, who manipulated the apparatus, it was possible to secure a fairly accurate short time record. A Deprez marker, together with a suitable time indicator, was adjusted to trace upon a smoked drum. With one method of recording a small mesh cap of copper wire was fitted over the rattles and connected with a flexible wire through a battery, the marker, and a curved brass plate. Touching the wire cap to the brass plate completed the circuit. With slight provocation vigorous movement resulted and the writer would hold as far back from the tip of the tail as possible and still be able to direct the tip so that it would strike the plate with each complete vibration. Fearing that the cap might be heavy enough to retard the motion, we tried again using a double strand of very fine copper wire wrapped twice around the rattles bringing this wire in contact with the plate as before. The average time of fifty-three consecutive vibrations, with the first method, was 30☛ (1ơ.001 sec.) with a mean variation of 100. The corresponding result for twenty-five vibrations by the second method, was 28σ, with a mean variation of 3.5σ.

To the writer two surprises are contained in this record, the first being the relatively great variability in rate of movement, the extremes ranging from about 10 to 50σ. After attention was directed to the variations in speed, they become marked even to the unaided ear, although no distinct rhythm can be detected.

The second unexpected result is that the pitch of the tone produced does not depend upon the speed nor upon the constancy of the tail vibration but upon the natural resonance of the rattles themselves. The pitch of this tone, as determined by two musicians with a very keen sense of pitch, and checked with accurately tuned forks, is between C and C#; the tone is expressed, therefore, by about 128 to 135 vibrations per second. Very marked changes in rate of tail, from the fastest that could be produced by marked provocation, to the almost quiescent state, did not cause a

fluctuation of the pitch beyond this approximate half-tone. The tone itself is exceedingly complex however, and it might conceivably vary with the number and size of the rattles. It was possible to detect, but not to identify, certain overtones.

The popular impression that the rattler uses his rattles as a warning that he is about to strike is regarded by Mr. Dill as quite erroneous. This snake, when striking normally does so first and rattles afterward, if at all. It will, for instance, strike at a bird placed in the cage, rattle, then strike again. It appears that the rattle is rather to terrify than to warn. It is also used as a defensive mechanism. The instinct to vibrate the tail is not peculiar to the rattlesnake, but is common to many other species, as, for instance, to the non-venomous king snake and the blue racer. MABEL C. WILLIAMS

STATE UNIVERSITY OF IOWA

A TICKET TO ST. LOUIS

I AM a schoolmaster. I am not earning a living for myself and family, though my position is counted a good one. I shall be a schoolmaster till I die: I have chosen teaching as my service, and am too old to change. My three sons will not be schoolmasters.

Before the war I was able to make ends meet. I could then devote all my time and energies to the duties of my position. Then came increase of passenger rates, and a war tax added, and I and my family have since stayed home. I even bought several liberty bonds and my children bought war savings stamps at the beginning.

Then came also increased freight rates and of cost of food, and I and my boys began gardening. Then came also increase of wages and decrease of competence in artisans, and I and my boys began doing our own repair work -carpentry, plastering, roofing, ditch-digging, etc. But, staying always home, and raising beans, and fixing spouts is not what I am paid for doing, nor does it get the best results from the long training I have had. And ever since the close of the war I have been vainly hoping to be allowed to devote my time again to my

teaching and research; for I am first and last growth of the tissue is different in different a schoolmaster.

The war having ended more than a year ago, I thought I should like to go to the meeting of the American Association for the Advancement of Science at St. Louis, to meet my colleagues from the other universities and to talk over plans for the future. Now at the last the poor old decrepit U. S. Railroad Administration, which, I verily believe, has done more than any other single agency to increase the cost of living, decides that this association is not educational! Therefore, its members are not entitled to the reduced fare previously granted to those attending "meetings of religious, charitable, educational, fraternal, or military character." This, the equivalent of This, the equivalent of 2 cents per mile, which was full fare before the war, may be granted for truly educational gatherings, such as those of public kindergartners; but it is not for such as we are: we pay 3 cents per mile with a war tax added, or we help the railroads by staying at home.

Such is the judgment of a high official in that administration (Mr. Gerrit Fort, assistant director), who is doubtless provided with a salary adequate to support him and his family while he renders such decisions. Hear him: "The term 'educational' taken in its broad sense could be construed to cover a very large number of conventions. It was necessary, therefore, to restrict its definition, and this was done by confining it to those conventions having to do with elementary education, such as meetings of school-teachers." This is the last straw!

SCHOOLMASTER

SPECIAL ARTICLES

THE PROTECTIVE INFLUENCE OF BLOOD
SERUM ON THE EXPERIMENTAL CELL-
FIBRIN TISSUE OF LIMULUS1

In the preceding communication we showed that the solutions of different salts, which are constituents of blood serum or seawater, differ in their effect on the cellfibrin tissue and that the amount of regenerative out1 From the Department of Comparative Pathology, Washington University School of Medicine, St. Louis, Mo.

solutions. If we cover a wound with 5/8 m NaCl healing may take place; a small piece of excised placed on a cover-glass and surrounded by a drop of NaCl solution may show a good outgrowth under the conditions of our experiment in which usually a small amount of blood serum was adherent to the piece. However, all of these solutions are inferior to the blood serum of Limulus. It was of interest to determine which constituent or combination of substances in the blood serum was responsible for the superiority of the serum, whether it was caused by the balancing action of salts or by another constituent.

Addition of calcium chloride in various quantities to the sodium chloride solution did not improve the latter and usually made it less favorable for the tissue. The addition of seawater in which the inorganic constituents are present in proportions similar to those found in blood serum, prevented an active outgrowth altogether. Inasmuch as it was possible that the alkalinity of the seawater was injurious to the tissue, we used seawater with a hydrogen ion concentration which corresponded to an approximately neutral solution. This did not improve the effect of seawater. The Van't Hoff solution mixture of salts was likewise much inferior to an isotonic NaCl solution. These results made it improbable that the beneficial effect of blood serum was due to inorganic constituents.

This conclusion was corroborated by the effect of the heating of blood serum. Heating the blood serum to 85° for a short time sufficient to coagulate a certain amount of its proteid destroyed the greater part of the beneficial effect of blood serum. Heating this filtered fraction still further to 100° for a short time, and thus producing an additional coagulation, made the blood serum as unfavorable as seawater; such heated and filtered blood serum had still the blue color of normal oxygenated Limulus blood. However, how far a proportionality exists between the intensity of heating and of loss of beneficial properties of the serum needs further investigation.

At present we may conclude that the specifically protective effect of blood serum is due not to the combination or inorganic constituents but to the proteid constituents of the blood. This may perhaps explain the fact that different blood sera may differ in their beneficial effect. We even found that the blood sera of diseased, anemic Limuli may become as ineffective or as injurious as seawater. Whether the action of microorganisms enters as a factor in the case of blood sera of anemic Limuli remains still to be determined.

LEO LOEB

A PRELIMINARY NOTE ON SOIL ACIDITY

WHATEVER may be the cause and nature of soil acidity, apparently part of this acidity is due to some of the materials which constitute the soil itself. This gives rise to the question as to whether the minerals from which the soils are derived are acid; and if not, what changes occur in these minerals to make them acid and what factors cause these changes. Therefore in some work on soil acidity that has recently been done in this laboratory, the problem was attacked along a line somewhat different from that usually followed. Instead of working with acid soils entirely, neutral and basic soils were also chosen and the one factor which probably, more than any other, has to do with the natural changes produced in the soil forming minerals—namely, water leaching through the soil-was investigated. After working with a few soils, it seemed advisable to experiment with the more abundant minerals which constitute certain types of soils, and with a few of their decomposition products.

Such materials as the following were taken for the experiments: soils, rocks, miscellaneous gravel, pure minerals such as quartz, hornblende, microcline and garnet, and some of the decomposition products of the above mentioned minerals and rocks such as silicic acid, kaolin, silica, etc. Nearly all of the rocks, gravel and pure minerals were found to be either neutral or slightly basic. The materials were leached with water containing

carbon dioxide, and analyses were made to determine what changes had occurred, both in the samples and in the percolated water.

The results from this work show that of all the samples that were leached, no matter whether the original material was basic or acid, the resulting material was acid; and that with the exception of the decomposition products such as silicic acid, kaolin, etc., nearly all of the samples became more acid. The fact should be emphasized here that all of the materials, with the exception of the soils themselves, were minerals or rocks which contained no organic matter. Hence the acidity was not due to organic matter.

From the above statements, the conclusion may be drawn that the compounds formed from some of the soil-forming minerals due to leaching, are an important factor in making soils acid.

Having shown then that some of the materials of which soils are composed, on being leached with water containing carbon dioxide, make soils acid, the next logical step in this research was to try to determine how these compounds give rise to this acidity.

This problem was attacked by determining the hydrogen ion concentration of neutral water extracts of the materials in question; and by determining the hydrogen ion concentration of similar extracts after different known quantities of standard calcium hydroxide had been added. A curve plotted from the results of these determinations should show (1) any excess of hydrogen ions in the solution; (2) the presence of any compound that is capable of taking up calcium hydroxide as a result of adsorption, by the formation of addition products, or by true chemical action; and (3) any excess of free hydroxyl ions. To illustrate, let the following figure represent the relation between the hydrogen ion concentration (expressed as P1) in a solution and the amount of calcium hydroxide that has been added. Then line ab shows a decreasing excess of hydrogen ions in the solution; bc that the hydroxyl ions are being removed from the field of action as fast as they are added; and cd, an increasing excess of hydroxyl ions.

The curves plotted from the results of the determinations made on acid soils and on the decomposition products of the soil-forming minerals are similar to the one described above, while those made on neutral or alkaline soils are similar to lines bc and cd of that curve. This apparently indicates that there are some dissociated acids or acid salts present in the solutions of acid soils, and of the decomposition products; and that with all of the materials some of the calcium hydroxide is entirely removed from the field of action. These statements are interesting, especially when compared with the conclusions drawn in regard to soil acidity from results obtained by the freezing point method. The conclusions

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by that method are contrary to the former of the above statements, but agree with the latter. Some other interesting facts concerning these curves are that where they first reach the neutral line, they show a lime requirement as determined by the so-called Jones2 method; and that where they leave the neutral line, they may indicate what Sharp3 and Hoagland term "potential acidity" or what Bouyoucos terms "maximum lime requirement." It is also interesting to note that the curves vary somewhat when bases other than calcium hydroxide are added to soils. Barium hydroxide gives rise to curves similar to calcium hydroxide, while sodium and ammonium hydroxides gives curves represented by lines ab and ed in the above figure.

1 Mich. Agric. Col. Exp. Sta. Technical Bul., No. 27.

2 Jour. A. O. A. C., Vol. I., p. 43.

Jour. Agric. Research, Vol. VII., p. 123. Mich. Agric. Col. Exp. Sta. Technical Bul. No. 27, p. 37.

This work is being continued with the hope that within a short time sufficient data will be obtained to warrant a more complete discussion of the subject. O. B. WINTER MICHIGAN AGRICULTURAL COLLEGE, EXPERIMENT STATION

ALABAMA MEETING OF THE ASSOCIATION OF AMERICAN STATE

GEOLOGISTS

ONE of the most successful and profitable annual field meetings of the Association of American State Geologists was held in Alabama, September 1 to 6, 1919, on invitation and under the able guidance of the state geologist, Dr. Eugene A. Smith. Headquarters were at the Tutwiler Hotel, Birmingham.

An instructive printed guide of 14 pages briefly summarizing the essential geologic features to be observed at each place visited in the state was prepared by Dr. Smith and associates. As originally planned, the program called for a division of the party into two sections (Highland and Coastal Plain), to be together only on the first and last days. This plan was later modified to exclude the Coastal Plain section, but was closely adhered to for the Highland section, which closed with a visit to the University of Alabama, so long and well known to geologists as the home of the distinguished host, Dr. Smith.

Much of the Highland region of the state, long known for its varied and complex geology, was covered by excursions, and many of the interesting features of physiography, structure, stratigraphy and economic geology, were reviewed. Among some of the more important localities visited were the famous Birmingham district, where opportunity was afforded for observing some of its more important geologic features, including visits to iron and coal mines, limestone quarries and industrial plants; the extensive productive graphite area between Lineville and Goodwater, the largest domestic producer of graphite; the marble quarries near Sylacauga; and Sheffield and Florence where are located the government nitrate plant and prospective water-power developments at Mussel Shoals on Tennessee River.

The geologists participating in a part or all of the excursions were: Eugene A. Smith and W. F. Prouty (Alabama), J. A. Bownocker (Ohio), G. F. Kay (Iowa), H. B. Kümmel (New Jersey), I. C. White (West Virginia), W. N. Logan (Indiana), S. W. McCallie and J. P. D. Hull (Georgia), W.

O. Hotchkiss (Wisconsin), Collier Cobb (North Carolina), H. F. Cleland (Massachusetts), Herman Gunter (Florida), W. A. Nelson (Tennessee), George Otis Smith, E. O. Ulrich and Charles Butts (Washington, D. C.).

THOMAS L. WATSON, Secretary

THE AMERICAN CHEMICAL SOCIETY.

VII

DIVISION OF BIOLOGICAL CHEMISTRY

I. K. Phelps, Chairman

R. A. Gortner, Vice-chairman and Secretary Chemotherapy of organic arsenicals: C. N. MEYERS. A discussion of the transitions of arsenic therapy leading up to the production of salvarsan. A chart showing the methods of approaching the mother substance is presented. The reduction process is briefly discussed, followed by a consideration of the chemical and physical properties, the toxicology, the impurities, and the preservation of salvarsan. The chemical and physical factors as related to the administration of the drug are discussed based upon clinical observations as a result of an extensive investigation of the methods used by leading dermatologists. Standard methods are recommended in order to eliminate reactions which unnecessarily result from faulty technique and improper use of chemical laws when salvarsan is used in organotherapy.

The chemical composition of arsphenamine (salvarsan): G. W. RAIZISS.

A comparative study of the trypanocidal activity of arsphenamine and neo-arsphenamine: J. F. SCHAMBERG, J. A. KOLMER AND G. W. RAIZISS.

Chemotherapeutic studies with ethylhydrocuprein and mercurophen in experimental pneumococcus meningitis of rabbits: J. A. KOLMER AND GORO IDZUMI.

Coordination of the principles of chemo-therapy with the laws of immunity and the successful application in the treatment of tuberculosis: BENJAMIN S. PASCHALL. The tubercle bacillus is protected by waxy substances consisting chiefly of unsaturated highly complex alcohols and equal quantities of phosphatides with which they form a colloidal complex and which in turn exists in close union, possibly physical, more probably chemical, with the protoplasmic substances of the tubercle bacillus, both proteid and carbohydrate in nature. Saponification breaks up this complex without destruction of the important immunizing substances and makes

possible separation by solvents. By this means toxic and caseating substances of the Cholin Muscarin group are eliminated as well as the ordinary poisons elaborated by the tubercle bacillus proteins and protein derivatives. Esterification of the fatty acids with ethyl alcohol forms a valuable immunizing substance as these fatty acids have so far been found not to conform to those found in our common food products. Esterification of the higher alcohols with salicylic benzoic, acetic or other suitable acids establishes a new side chain or anchoring group which greatly enhances the reactivity between the antigens themselves and the receptors of the tissue cells so that absorption of these alcoholic esters takes place in the tissues in a few days without producing caseation and tissue necrosis even when given in doses of from 3 to 5 c.c., and following these injections of the mixed esters specific wax digesting ferments form in sufficient concentration to split the protective waxes from the tubercle bacillus living within the host whereby disorganization and destruction of the organism ensues and the patient absolutely recovers and remains well. Thus combining the principles of chemico-therapy with the laws of immunity, a new substance was found for the treatment of all forms of tuberculosis which was successfully used in our own practise and named by us Mycoleum.

The chlorinated antiseptics: Chloramine-T and dichloramine-T: ISAAC F. HARRIS, Ph.D., Research Laboratories, E. R. Squibb & Sons, New York. Toluene-p-sodium-sulfonchloramine (chloramine-T) when prepared in state of high chemical purity is an extremely stable compound, both in crystalline form and in solution. Toluene-p-sulfondichloramine (dichloramine-T) is quite stable when prepared in very high purity chemically dry and protected from dust, organic matter and sunlight. Pure dichloramine-T can be kept in pure, anhydrous chlorcosane, without appreciable decomposition, for several months, if protected from continuous action of direct sunlight. In the reactions between the proteins of the tissues and Dakin's solution, chloramines of the proteins and free sodium hydroxide are formed. The latter furnishes the solvent power attributed to Dakin's solution. When the chloramines react with bacteria and necrotic protein matter, chloramines of the proteins are formed and toluene-p-sulfonamide is set free. The latter is inert and innocuous. The chloramines can be employed with more precision and in greater concentration than Dakin's solution.

An agent for the destruction of vermin-method of application: ALBERT A. EPSTEIN. (By title.)

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