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We also circulate among the officials here about twenty of the journals, which are carried out and brought in daily after three days' use.

Special library service in The Barrett Company: E. C. BUCK.

Library service in the chemical department and chemical department laboratories of the E. I. du Pont de Nemours & Company: F. I. GALLUP. The paper outlined the du Pont Chemical Department Library organization, covering especially the following points: (1) Informing the librarians of new work to be undertaken, (2) a monthly exchange of accession reports, (3) the monthly abstract, (4) the patent files and patent catalogue, (5) special research catalogue of references, (6) classification and index of information in chemical department reports, (7) bibliographical work, (8) personal.

Symposium on the Future of Certain Americanmade Chemicals

Some present-day problems of chemical industry: R. F. BACON and W. A. HAMOR.

A possible menace to American chemical independence: W. D. COLLINS. This paper noted a few instances of unsatisfactory deliveries of chemicals and apparatus for regular analytical work. In some lines American-made products are so superior to the foreign supplies that very few analysts would care to use the foreign articles at any price. In other lines there is some doubt as to the inferiority of American products available at the present time. Many buyers of supplies for analytical, industrial and educational laboratories would pay higher prices for satisfactory American products, but may not be willing to sacrifice time and reliability of results by using inferior products if supplies formerly used again become available. It is suggested that the industrial section or the society either appoint a new committee or enlarge the field of some committee already in existence to canvass the situation in regard to the quality of chemicals and apparatus for regular laboratory work. Such a committee, working, should be able to secure cooperation between buy. ers, sellers and manufacturers which would remove any lingering desire on the part of chemists for foreign-made reagents and apparatus for everyday use in the laboratories of schools, universities and industries.

Quality first to insure increased success of the chemical industry of the United States: JOKICHI TAKAMINE, JR.

Phenol: ALBERT G. PETERKIN. Cellulose acetate: H. S. MORK. Unusual organic chemicals: HANS T. CLARKE. Also W. J. HALE, L. M. TOLMAN, H. A. METZ and General Information Discussion.

General Papers

Tactical uses of smoke (lantern): BYRON €. Goss.

Chemical work in the canning industry: W. D. BIGELOW.

Corrosion tests on commercial calcium chloride used in automobile anti-freeze solutions (lantern): PAUL RUDNICK. Three proprietary products were tested for their effect on aluminum, copper and cast iron. Polished plates of these metals were immersed in solutions of the concentration directed by the manufacturers. The plates were suspended in pairs of copper and aluminum, copper and cast iron, and aluminum and cast iron, and also a set of all three, by means of copper wire attached to the emergent ends of the respective plates. The tests were continued for thirty days, the loss or gain in weight of the plates being noted every other day. The curves plotted from these results show not only that aluminum is attacked most severely, iron next, and copper least, as would be expected, but also that the rate of corrosion increases sharply on the eighteenth to twentieth day of immersion.

Oxidation in the manufacture of T.N.T.: A. S. EASTMAN. The final stage of the nitration of toluene in the manufacture of T.N.T. is carried out at such a high temperature that there is considerable oxidation of the nitrotoluenes, by the mixed acid. The extent of this oxidation is indicated by the presence of 15 to 20 per cent., of HNOSO, in the spent acids. This represents the reduction product, and it was desired to identify a corresponding quantity of oxidation products. 2-4-dinitrobenzoic acid was isolated. cent. of the toluene is lost by oxidation to organic acids. The gas evolved during nitration contained CO2, CO, N, and O, in quantities sufficient to lower the yield of T.N.T. by 4.9 per cent. This gas varies in composition, but may contain sufficient CO to be explosive, causing the top of a nitrator to be blown off, without detonating the T.N.T.

1.24 per

A new bomb calorimeter for industrial laboratories: W. L. BADGER. The only feature of this bomb that is radically different from other well

known types is that it is made of Monel metal and is not lined. The sulphuric and nitric acids formed during the combustion of the coal sample attack the bomb very slightly. Gravimetric sulphur determinations give the sulphur correction directly. Since some of the acids are neutralized by the metal of the bomb, the nitric acid correction can not be determined, but is ordinarily too small to affect the accuracy of determinations for industrial purposes. The result is a bomb which gives results agreeing with the standard types much closer than the ordinary errors in sampling and which can be made for a small fraction of the cost of any lined calorimeter.

Non-metallic inclusions in steel: E. G. MAHIN. In this paper the origin and nature of inclusions is briefly discussed and the general effects upon the properties of the steel are noted. The principal effects are of two classes: (1) They produce the same kind of weakness as would result from cavities of similar size and form. (2) Ferrite segregation usually occurs in such a manner as that inclusions are found as nuclei of ferrite grains. If the steel is forged or rolled these grains and their inclusions become elongated and ordinary thermal treatment fails to destroy the resulting banded structure. The various theories that have been advanced to account for these facts are discussed, particular attention being devoted to the idea of Stead, to the effect that iron phosphide is entirely responsible for ferrite segregation and that inclusions have a purely incidental connection with this phenomenon. Experimental work is described, illustrated by lantern slides, as a result of which the conclusion is reached that the persistence of ferrite bands is, in fact, largely or entirely due to phosphorus, but that inclusions exert an effect upon the crystallization of ferrite which is independent of the presence of phosphorus. Certain hypotheses are advanced to account for the observed facts.

Mineral rubber: GUSTAV EGLOFF.

Manufacture of castor oil: J. H. SHRADER. A description of the technology of castor oil manufacture as practised by the castor oil manufacturers, together with that of the government plant at Gainesville.

Possibility of commercial utilization of oil from cherry pits, tomato seed and grape seed: J. H. SHRADER. The possibility of the commercial utilization of the canning house by-products of cherry pits, tomato seed and grape pomace is considered in the light of the economic question involved in

assembling the raw material before manufacturing the finished product, together with a brief description of the technical questions involved.

Sugar saving by home-grown sugar beets: JOHN M. ORT and JAMES P. WITHROW. This work was undertaken as a war help, though interest in the subject in rural communities and state institutions has existed for years. In the ordinary manufac ture of beet sugar, the sugar is separated from the syrup by crystallization and the sugar then refined. This leaves most of the salts and strongly flavored organic impurities in the residual impoverished syrup of molasses so that it is fit only for cattle food or fertilizer. It is this material also which has rendered difficult the elimination of the beet flavor from the syrup from sugar beets. Otherwise the making of this syrup for home consumption would long ago have been an important rural home industry. Home cultivated sugar beets properly trimmed, peeled, decored and sliced were found to yield a bright syrup with good taste upon treatment with hot water after a preliminary wash and then boiling down. This gives a sweetening available for many culinary purposes and in which, with ordinary care, the characteristic beet flavor is nearly eliminated or not too prominent for use as syrup. Contrary to the published statements no simple treatment has been found which will consistently render this syrup entirely palatable but it can be used in all cases with as little real basis for objection as the sorghum syrup so much made in rural districts. It is hoped that more resourceful investigators will succeed in the entire elimination of this disagreeable flavor, and in every case. We have but dipped into the subject.

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SCIENCE

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GROWTH IN ORGANISMS1

THE main proposals discussed in this address were as follows:

1. The development of an organism from the spore or embryonic stage includes the two processes of auxesis or enlargement and of differentiation both in the single cells or elements and in the organs.

2. The present studies are based upon the conception that living matter is composed mainly of pentosans and albumins or albumin derivatives with lipins as a minor component. The proportion of the main components may vary from nearly a hundred per cent. to nearly zero.

3. The principal and characteristic substances of the two groups are practically nondiffusible and hence come together only as an intimate mixture in a colloidal condition, with varying arrangement.

4. Growth of living matter consists of hydration with accompanying swelling and of accretion of solid matter, the two processes being actually independent.

5. The hydration of the substances belonging to the two main components is affected in an opposite manner by hydrogen ions, and is variously modified by temperature and other conditions: the rate and amount of growth is a resultant of several reactions.

6. Accretions of new material include the absorption of salts which tend to restrict hydration and the incorporation of amino-compounds. So-called nutrient salts do not constitute food but may act as catalysts or releasers of energy in other substances and as controls.

7. The enlargement of cells is almost entirely by the swelling which results from hy

1 Presidential address, Pacific Division of the American Association for the Advancement of Science meeting at Pasadena, June 19, 1919. Manuscript abbreviated by the author.

dration in their earlier stages, and later the enlargement of the syneretic cavities in the colloidal structure is followed by the distending or stretching action of osmostic pressures in the vacuoles thus formed.

8. Illustrations by records of growth of leafy stems, joints of cacti, fruits of Solanum and trunks of trees.

The development of an organism from the single- or few-celled stage to the stature of the adult individual is generally characterized as growth. One of the first facts that comes to the notice of the observer who follows the life history of an animal or plant from the egg or the spore or from the resting stage in a seed to maturity is that all parts of the individual do not enlarge at the same rate, and that if attention be fixed upon the most readily available object for such a study, the root or shoot of any plant, it will be seen that the power of expansion seems to reside only in the region of the tip in the case of the root and in the tip and in certain regions in the younger internodes of stems, while such organs as the leaves of grass elongate by the action of a growing zone at the bases. There are of course many specializations of this action such as those displayed by simple organisms in which a single cell is the inidvidual and when this reaches full size all possible growth is accomplished. As our principal purpose in the present discussion is to present the action of the protoplasm in growth it has been found most convenient to use facts discovered by the measurement and analyses of plants consisting of many millions of cells.

With magnifications of much less than a hundred, we readily see that the embryonic cells of a plant which may be imagined as of a cubical or prismatic form and consisting of a dense mass of colloidal matter, become larger, that they also change form, show new structures in the mass and that the enclosing wall takes on a variety of forms. These changes determine the final part which the maturing cell may play in the complex processes of the organism. The architecture of the plant includes many beautiful mechanical designs and it would be well to guard against

the error of considering it as simply a set of sacs, test tubes, and bits of jelly by recalling the fact that it is, like all living things, an engine which not only picks up its fuel, manufactures it into briquettes, or their physiological equivalent, burns this fuel, the derived energy being used in a variety of ways. but while this is going on the machine is also adding to, repairing and altering its own parts. This, however, does not imply that any special or mysterious "life forces" are concerned. The physiologist may in fact identify a large number of the things that may happen in the cell and he may imitate many of them and the progress of science will be marked by the successive subjugation of others, but to assemble the material in a way to obtain the complexity and the sequences of reactions of living matter is beyond our capacity for manipulation, and our failure may not be ascribed to the lack of any elusive vital spark.

The taste for polysyllabic definitions of protoplasm has waned and we are not so much concerned with inclusive descriptions as with an understanding of the nature of the substances which enter into its composition and how these react when subjected to conditions which may prevail in the cell. Protoplasm when viewed with a low power microscope appears to be a silvery translucent mass of material like a highly hydrated jelly, which, in fact it really is, being composed of about one to two parts of solid matter to about two hundred of water. The constituency of the solid part, or the residue which is obtained by driving off all of the water is a matter of no little interest, since it is upon this physical basis that all of the properties of the organism

rest.

The proteins or albumins are invariably present, and the transformations in the highly complex molecules of the nitrogenous compounds in living matter offer some tremendous difficulties in interpretation and at the same time yield the material for some of the most romantic chapters in biological science. Present in every cell, these substances may not move from one protoplast to another ex

cept in the highly hydrated state known as peptones, or when broken apart into comparatively simple amino-compounds. Gelatine, a substance of an albuminous character, has been widely used in experimental work which had for its purpose the determination of the properties of living matter, but we are now so far advanced as to know that it may represent the qualities of the protoplast only in so far as these may be identical with amphoteric compounds. In other words, the behavior of gelatine may be used to some extent to simulate the reactions of protoplasm which consists largely of albuminous substances. This is not a universal condition and in fact is the exception in plants.

Lipins or fatty substances form an important part of the living matter of animals and in their growing cells may constitute as much as two per cent. of the solid matter, amounting to one part in a thousand of the total weight. The lipins may unite with phosphoric acid, with carbohydrates, or with nitrogenous substances such as the aminoacids; giving diverse materials, the action of which in the life processes is but dimly comprehended.

The physiologist who devotes himself to the study of life as exemplified by animal forms deals with a protoplasm in which the proteins

and lipins predominate, and is excusably apt to believe in the universality of the properties he uncovers by a study of their reactions. The presence of mucin, gums and mucilages in living matter has long been known, but the determination of their definite occurrence as a component part of the mechanism of the cell was first acomplished at the Desert Laboratory. Numerous analyses show that the pentoses and their condensation products the pentosans are abundant in plant cells, and that they may form a larger proportion of its dry weight than do the proteins or nitrogenous substances.

Here however, we must avoid the mistakes of our predecessors by assuming a universal condition. Specialized organs or cells, eggs, spores, pollen cells, etc., may have a protoplasm in which the protein material may make up almost the entire solid matter, and

at the same time it is not to be assumed that the main components are evenly distributed throughout the mass of the protoplast, as it is very well known that the nucleus and other special organs of the cell are high in albumins. Consultation of available information on this point shows that in bacteria for example over 90 per cent. of the solid matter may be albuminous. The analyses of cacti made by Dr. H. A. Spoehr at the Desert Laboratory show that not more than a tenth of the living matter is proteinaceous, and that the greater part of the cell content is carbohydrate, pentosans, of which gum arabic, tragacanth, mucilage and agar are common examples, these being in fact combinations of the simpler pentose and hexose sugars.

Miss Stewart of Barnard College has recently described the manner in which pentosans formed in the cytoplasm accumulate in a layer next the wall leading some observers to believe mistakenly that they were formd by the hydrolysis of wall material. In other cases masses were formed in cavities in the protoplasm. Gross chemical analyses determine the presence of such substances in material in which they occur only in finely divided form in the colloidal mixture and may not be detected by microchemical methods. At present our knowledge of these substances is confined chiefly to their action as a part of the hydration or growth mechanism, and it is by no means clear that they are not more or less included in the metabolic cycle.

These statements are not to be taken as implying a simple composition for protoplasm: The different and various pentosans on the one hand and the amino-compounds built up by the plant or derived from albumins have various special characters although the first agree in being weak acids, and the second are amphoteric, capable of acting as either acids or bases according to conditions. As an example of these differences there has been much discussion as to whether or not protoplasm was soluble or miscible in water. It is obvious that living matter in which the pentosan was a mucilage like gum arabic would be miscible with water, while a pentosan like

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