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oxidation of organic substances. The occurrence of catalase is so general in plant and animal tissues that its existence certainly must have a significance. Loew conceived the idea that peroxides are formed in the cells in the process of respiration, and that the catalase saves the protoplasm from being injured by these peroxides by decomposing them as fast as they are being formed. Usher and Priestly have shown that in plants at any rate hydrogen peroxide is actually one of the substances formed under the action of light and, if not immediately destroyed by catalase, will bleach the chlorophyl and thus interfere with the photosynthetic reaction. In the last few years the work of Appleman, Zaleski and Rosenberg, Loevenhart and Kastle, Alvarez and Starkweather, McArthur and notably of Burge have drawn attention to the probable function of catalase as an index of metabolic activity. Our interest in catalase originated with this fundamental problem of the relation of catalase to tissue metabolism. It may be mentioned that since our research has been in progress a number of papers appeared by Becht, Stehle," Reimann and Becher which not merely challenge the interpretation which Burge and others place on catalases, but also their experimental findings.

The observations of which this is a preliminary report, although not bearing directly upon the fundamental problem of the catalase function, throw nevertheless interesting light on the subject. The literature contains many instances of inorganic substances, such as colloidal platinum and several others which possess remarkable catalytic power, and bring about reactions characteristic of enzymes. Thus Sjolleman' found that colloidal manganous oxide gives all the typical reactions for oxidases. Again Wolffs showed that certain

3 Usher and Priestly, Proc. Roy. Soc. London, 77B, 369, 1906.

Becht, Am. J. Physiol., 48, 171-191, 1919.
Stehle, J. Biol. Chem., 39, 403, 1919.
Reimann and Becker, Am. J. Physiol., 50, 54,

1919.

7 Sjolleman, Chem. Weeklad, 6, 287–294, 1909. 8 Wolff, C. r. Ac. Sc., 146, 142–144, 781-783, 1908.

iron salts can play the part of peroxidases, while Bredig's "inorganic ferment"-a colloidal platinum-is capable of decomposing hydrogen peroxide as vigorously as catalase. There is, however, no record of organic substances simulating a biological process. We have discovered a group of aromatic hydrocarbons and their derivatives which give the typical catalase reaction. Such substances may undoubtedly help to throw light on the chemical structure and characteristics of the enzyme itself.

Our numerous experiments which we will report in detail later arose from the accidental observation that an enzyme preparation preserved with toluol had acquired a remarkably increased capacity for decomposing hydrogen peroxide. It was at that time also that a paper appeared by Euler and Blix10 on yeast catalase in which these authors state that the catalase is activated by several substances, toluol among them. The idea of an activation of the enzyme by toluol seemed entirely improbable from our experience, because we found that even such minute quantities of toluol as 0.05 or 0.1 ccm. can decompose hydrogen peroxide. We undertook therefore to examine a number of related organic compounds in the hope of finding whether this non specific catalase reaction is in any way associated with the chemical structure of the organic catalysts. Starting with benzene we studied a number of its homologues and some of its derivatives. Benzene was found to react most vigorously, 0.2 ccm. liberating about 20 ccm. of oxygen from hydrogen peroxide in a manner so closely resembling the effect of an active enzyme preparation that one could not tell the difference unless informed as to the material used in the test.

The aromatic hydrocarbons of the benzene group form a series according to the number of methyl radicles attached to the ring with a gradually decreasing power to decompose hydrogen peroxide, thus:

Benzene>Toluol>Xylol>Mesitylene

• Bredig, "Anorganische Fermente," 1901. 10 Euler und Blix, Ztschr. physiol. Chem., 105, 83-114, 1919.

The reaction is not general for the aromatic hydrocarbons, but is specific for those of the benzene series. Hydrocarbons with more than one benzene ring, like diphenyl and triphenyl methane, benzidine, naphthalene and anthracene all proved to be inert. Heterocyclic compounds also gave negative results.

We mentioned already that the increase in the number of methyl groups in the benzene ring results in a corresponding decrease of the catalytic activity of the compound. The introduction into the ring of a carboxyl group, an NHNH, group or of phenol groups renders the hydrocarbon incapable of decomposing hydrogen peroxide. On the other hand, the presence of nitro, amino and aldehyde groups, or of a halogen atom does not prevent the

compound from breaking up of hydrogen peroxide, though its power is much less than that of the unsubstituted hydrocarbon. Aniline, nitrobenzene, benzaldehyde and chlorbenzene decompose hydrogen peroxide, but dichlorbenzene, benzylchloride or benzoylchloride, were found inactive. Adrenalin, both the base and the hydrochloride, decompose hydrogen peroxide though very feebly.

A more detailed discussion of the catalaselike reaction of benzene and its homologues is reserved for the near future. Suffice it to say that we have satisfied ourselves that this decomposition is not caused by changes in surface tension. SERGIUS MORGULIS, VICTOR E. LEVINE

CREIGHTON MEDICAL COLLEGE

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A SIMPLE DEVICE FOR SHOWING BY A
HYDRAULIC ANALOGUE THE EFFECT
ON THE POTENTIAL

PRODUCED

DIFFERENCE BETWEEN THE
TERMINALS OF AN ELEC-
TRIC CELL WHEN THE
CIRCUIT IS CLOSED

THE Lodge theoretical paddle wheel device shown by Professor Kimball in Figs. 336 and 337 of his "College Physics" (ed. 1917) suggested to the writer an arrangement which would render possible an actual lecture demonstration.

Into the glass U-tube of Fig. 1 a stream of water is injected at P. The water is removed at the exits E and E', the sizes of which may be controlled by adjustable pinchcocks C and C' on the rubber tubes T and T'. The "current" is controlled by the pinchcock C" or one's fingers on the rubber tube T." The inflow at I may be controlled by the faucet to which the apparatus is attached. When C" is closed, h represents the potential difference on open circuit. Upon opening C," level B falls and A rises: h'<h or the potential difference decreases when the circuit is closed.

My friend, Professor F. A. Saunders, has modified the arrangement by placing the water-spout at P' (Fig 2). This is an improvement from the pedagogic standpoint as the source of gross energy in an electric cell lies at the surface of separation between one plate and the electrolyte. He also suggests removing the injected water at but one point, E" (Fig. 2).

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205

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*Temperature scales and thermometer scales: E. W. WOOLARD. (May.)

Shall we adopt a half-degree absolute centigrade scale instead of the Fahrenheit? CHARLES F. MARVIN. (Not published.)

The physics of the aurora: W. J. HUMPHREYS. (Abstract to be published.)

*The auroras of March 22-25, 1920: HERBERT LY(July (1).)

MAN.

The most intense rainfall on record: B. C. KADEL. (May.)

*New aerological apparatus: S. P. FERGUSON. (June.)

Temperatures versus pressures as determinants of

winds aloft: W. R. GREGG. (Abstract, May.) *Daily wind charts for stated levels: C. LEROY MEISINGER. (May.)

Cloud base altitudes as shown by disappearance of balloons and kites: O. L. LEWIS. (July (9).) *Cloud nomenclature: CHARLES F. BROOKS. (July (1).)

*Some meteorological observations of a bombing pilot in France: THOMAS R. REED. (April.) Project for local forecast studies: R. H. WEIGHTMAN. (March.) (By title.)

Climatic conditions in a greenhouse as measured by plant growth: EARL S. JOHNSTON. (Abstract, April.)

Modifying factors in effective temperature: ANDREW D. HOPKINS. (April.) Relation of rainfall to the grazing capacity of ranges: J. WARREN SMITH. (June.) Separates have been or are to be made of those starred, and may be obtained from the U. S. Weather Bureau, Washington, D. C.

The American Meteorological Society, the project of which was announced in SCIENCE, just a year ago (August 22, 1919, pp. 180-181), and of which progress was reported (December 12, 1919, pp. 546547) and organization in December announced (March 12, 1920, pp. 275–276), has grown with unexpected rapidity to a membership of nearly 1,000. Plans are being made for the organization of a Brazilian division of the society, and it is probable that a Pacific division will be organized when the Pacific section of the American Association for the Advancement of Science meets next summer.

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The Kaufler-Cain formula for diphenyl derivatives: OLIVER KAMM and C. S. PALMER.

BB'-dichlorodiethyl ether: the oxygen analogue of mustard gas: OLIVER KAMM and J. H. WALDO. The chlorination of acetone: A. W. HOMBERGER and M. BORRIES. Technical acetone was purified and treated with dry chlorine in sunlight. During the chlorination three distinct steps were noted. The first step was completed at the close of the first half hour. No hydrochloric acid was liberated during this stage. The second step lasted two hours. The heat of reaction was much higher than in the preceding step and whenever the temperature rose over 80 degrees violent reaction, resulting in flames, took place. A third step took place after this second reaction with no violent action and a temperature maintained itself below 80 degrees, and no tendency to burst into flames. During the second and third step hydrochloric acid was liberated, much more during the second than the third step. The resulting liquid of chlorination was submitted to distillation under diminished pressure and three distinct fractions obtained. The three fractions, when redistilled, showed definite and well-defined boiling points and properties. Each of these products is being investigated at present.

The use of a chart in the study of organic chemistry: CHAS. W. CUNO. The studies are divided into three great divisions, the memory studies, the reasoning studies, and the constructive studies. The two great memory studies are history and the languages. History concerns itself with data and dates, or to put it abstractly, with sequence and facts. Language concerns itself with interpretation. If we examine the reasoning studies such as chemistry we find they have a language and sequence and data that need to be made a part of the memory before the student can very well reason intelligently. In organic chemistry the language is exceedingly difficult and the data and sequence very voluminous. The use of a chart such as the one published by the author has its use, therefore, to help the student in acquiring the

data, sequence and language of organic chemistry.

The mechanism of some reactions involving the Grignard reagent: HENRY GILMAN. It has been conclusively proved that the reactions of ketenes are not restricted to primary addition to the ethylenic linkage. The benzoate of triphenylvinyl-alcohol was obtained when the addition compound of diphenyl ketene and phenyl magnesium bromide was treated with benzoyl chloride. The Grignard reagent, therefore, has added to the carbonyl group. Preliminary experiments on the mode of reaction of the Grignard reagent and phenyl isocyanate (and phenyl iso-thiocyanate), indicate the following: first, but one molecule of phenyl magnesium bromide adds; second, addition takes place on the carbonyl (and thio-carbonyl) linkage; and, third, addition is probably restricted to this linkage, as with the ketenes.

The nitration of certain halogenated phenols: L. CHAS. RAIFORD. In preparing halogenated o-aminophenols with which to test further the migration of acyl from nitrogen to oxygen (J. A. C. S., 41, 2068 (1919)), several of the brominated cresols were nitrated according to the method used by Zincke (J. pr. Chem. (2), 61, 561 (1900)), who found that in the meta series the halogen atom para to hydroxyl was replaced by the nitro group, while in the ortho and para series the atom ortho to hydroxyl was replaced. In none of these cases did he report the formation of isomeric nitro compounds in a single experiment. In the present work it has been found that the dibromo and tribromo-ortho cresols, to which Zincke has assigned the structures

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both give isomers when they are nitrated as indicated above. The structures of the isomers, as well as the mother substances, are under consideration.

Action of aromatic alcohols on phenols in the presence of aluminum chloride: RALPH C. HUSTON. Earlier work has shown that aromatic alcohols (primary or secondary) are readily condensed with aromatic hydrocarbons such as benzene, toluene, etc., to form diphenyl methane or derivatives thereof. In the present work benzyl alcohol was allowed to react at relatively low temperatures with phenol in

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A new color reaction for phenols based upon the use of selenious acid: VICTOR E. LEVINE. Phenols in contact with a solution of 0.5 per cent. selenium dioxide or 0.75 per cent. sodium selenite in concentrated sulphuric acid give rise to a pale green, olive green, emerald green, blue-green or purplish blue color. Often several colors are observed simultaneously. On standing, on heating or on the addition of water the characteristic color or play of colors disappears, giving way to a dark brown, reddish brown or brick red. The reactions is of great sensitivity and of wide applicability. following types of phenols respond to the test: Mono-, di- and triphenols, phenolic ethers, aldehydes, alcohols and acids, glycosides yielding phenols on hydrolyses, dyes and alkaloids possessing phenolic groups. Nitrating the phenol abolishes the reaction, for o-nitrophenol, p-nitrophenol, diand trinitrophenol yield negative results. Phenolic aldehydes and acids give extremely faint reactions. The following compounds tested prove the general value of the reaction: phenol, amidol, anisole, phenetole, phenacetine, the cresols, salicylic aldehyde, salicylic acid, acetyl salicylic acid, methyl and phenyl salicylates; pyrocatechol, guaiacol, vanilin, vanillic acid, piperonal, resorcin, hydroquinone, pyrogallol, phloroglucine; eugenol, thymol, carvacrol, a- and B-naphthol, chrysarobin; the glucosides, arbutin, phloridzin; the opium alkaloids, morphin, heroin, dionin, narcotine, narceine, papaverin; the dyes, orcein, alizarin, purpurin. The reaction proves very useful in detecting phenols in solid or liquid state. Phenols dissolved in water or in an organic solvent should first be evaporated in a porcelain crucible and the test made on the dry residue. A beautiful ring test may be obtained by the addition of a chloroform or amyl alcohol solution of the phenol to the selenium reagent. A bright emerald green is observed at the point of junction of the two liquids.

The green compound remains with the sulphuric acid and does not dissolve in the organic liquid. The course of the reaction may be explained on the ground that the phenol decomposes the selenous acid with the formation of free selenium. This dissolves with a green color in concentrated sulphuric acid to form selenosulphur trioxide.

A

A note on the differentiation of acetic anhydride from glacial acetic acid: VICTOR E. LEVINE. differentiation based upon chemical tests may be made as follows: (1) A few drops of 0.5 per cent. selenium dioxide in concentrated sulphuric acid added to acetic anhydride results in the formation of elemental selenium, which appears as brick-red colloidal solution or precipitate. Glacial acetic acid is not affected by the selenious acid reagent. (2) Ten drops of acetic anhydride are shaken with 2 c.c. chloroform in which a few crystals of cholesterol have been dissolved. On the addition of 20 drops of concentrated sulphuric acid a fleeting purple is developed changing to blue and finally to deep green. With or without glacial acetic acid a lemon yellow color forms, which quickly goes over to deep orange, cherry red or burgundy red.

The poly-phenyl ethers: HILTON IRA JONES. The decomposition of amines at high temperatures: FRED W. UPSON.

Oxalyl chloride in the synthesis of the triphenylmethane dyes: HARPER F. ZOLLER. Oxalyl chloride may be used in the place of phosgene or Michle's ketone in the condensing of aniline and its derivatives for the production of dye stuffs of the magenta type. The use of fused zinc chloride increases the yield of the colored base just as was found true in the case of phosgene. The calculated molecular quantities of aniline or its derivatives are mixed with a corresponding amount of oxalyl chloride necessary to produce a given dye. This mixture is heated in a flask bearing a reflux condenser and suspended in a hot water bath. Crystal violet (hexa methyl tri amino triphenylmethane) para rosaniline (tri amino triphenylmethane) have been prepared using oxalyl chloride in their synthesis. No accurate study has been made of the yields of the dyes using these synthesis. quantity obtained using the above method amounted to about 50 per cent. of the theoretical. The synthesis is described as a very convenient laboratory method of producing the dyes in small and very pure quantities.

The

The benzoic acid ester of trichlorotertiary butylalcohol or chloretone benzoic acid ester: T. B.

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