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Solids in Solution, mg./litre

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DISCUSSION AND CORRESPONDENCE The report also contains the results of anATMOSPHERIC POLLUTION1

alysis of the rainfall at Georgetown, British The Advisory Committee on Atmospheric Guiana, the nearest land in the direction of Pollution has published its fourth report sum

the prevailing east-northeast trade winds beming up the observations in the year 1917–

ing the shore of Morocco, distant 3,000 1918.

nautical miles. There can be little doubt

that the solids contained in the rain waters The full lists showing in detail the monthly deposit figures at various stations are not

collected are those normal to the rains of the reproduced, inasmuch as these have been al- trade winds, with perhaps some derived from

the coastal sea-spray. ready published in the Lancet; but full returns from two stations, Newcastle and Mal

The average results over the two years 1916 vern, are given; and these give the highest

and 1917 were as follows: and lowest deposits. Figures of total solids deposited monthly

Ca

7.95 are given for all stations, 24 in number, the

Mg

3.44 months being on a thirty-day basis.

K

2.77 In many instances the rainfall as measured

Na

16.36 at these stations did not agree with the

AIO,

0.58 amount obtained by the official Meteorological

Fe0g

1.97 Office gauges but this is easily explained when

0.2 it is remembered that the gauges of the com

CL,

33.93 mittee are often on roofs and are thus

SO,

12.02

9.78 elevated. The rainfall is given in millimeters,

NO,

11.57 and it would be well if we in the United

ΝΗ,

0.12 States would follow this example.

100.69 At a given London station the data for the half year, October to March, 1917–1918, were: It is shown that 55 per cent. of the solids Rainfall 43 mm.; tar 0.14 metric ton per

in solution in the rainfall are cyclic sea salts, square kilometer; carbonaceous matter other than while 45 per cent. must have been derived tar 2.18 tons; insoluble ash 3.50; soluble ash 4.15; from atmospheric sources. or total solids 11.41 tons. Of the soluble matter

The report also contains an account of there were 1.46 tons of sulphate, 0.63 tons of certain experiments made to determine the chlorine, and 0.05 of ammonia.

best method of measuring continuously the No relationship can be discovered between suspended impurity in the air. A. M. the deposit of insoluble matter and the

CAROTINOIDS AS FAT-SOLUBLE VITAMINE amount of rainfall. With the soluble matter,

My attention has been called to Steenbock's however, it is different, and in general it may

interesting observation, in SCIENCE of October be said to vary directly as the rainfall. The

10, that yellow corn and the colored roots, relation may be roughly expressed by the

such as carrots and sweet potatoes, are richer formula, S=0.058 R + 2.5, where R is the

in fat-soluble vitamine than white corn and rainfall in mm. and 8 the deposit of soluble

the pigmentless roots and tubers. A number matter in tons per square kilometer. It is

of other instances are noted in which fatnot suggested that this expression can be used

soluble vitamine and carotinoid pigment octo find the soluble deposit when the rainfall

cur simultaneously. The fact that these relais known but gives only the general nature of

tions have led Steenbock to the provisional the relationship.

assumption that the fat-soluble vitamine is 1 Meteorological Office. Report on Observations one of the carotinoid pigments has prompted 1917-18. Advisory Committee on Atmospheric

me to call attention to a number of cases Pollution, London, 1919.

where this relation apparently breaks down.

а

Drummond' has recently tested the pos- like cottonseed oil. Fresh cottonseed oil, after sibility of carotin being the fat-soluble being purified from resinous material, has a vitamine by feeding both crude and crystal- beautiful golden yellow color and is rich in line preparations of the pigment to rats, al- carotinoids. It should also contain an abunthough the question may be raised as to the dance of fat-soluble vitamine to be in keeplogic of testing the relation to fat-soluble ing with Steenbock's assumption. Apparently vitamine of a substance of which is not nat- this is not the case since both bleached and ural to the body of the animal

upon

which the unbleached cottonseed oil has been found to test is performed. Carotin is not found in be free from vitamine. The oil from yellow the body of the rat.

corn, similarly, should contain the vitamine, The writer has recently reported the fact but the same investigation has reported that it is possible to raise a flock of chickens failure to obtain growth with diets containfrom hatching to maturity on a diet free, or ing the commercial unbleached corn oil. at most containing the merest traces, of It is thus possible to cite a number of carotinoids. Not only did the mature hens instances where the probable relation between lay eggs whose yolks were free from caroti- carotinoids and fat-soluble vitamine breaks noids, but a second generation of carotinoid- down. No doubt others could be found. The free chicks were hatched from them. Only writer regards the instances of a simultaone of two possible conclusions can be drawn neous occurrence of fat-soluble vitamine and from this experiment. Either the fat-soluble plant carotinoids as fortuitous. The similarvitamine and the yellow plant pigments are ity of certain of the properties of the two not related physiologically or the fat-soluble kinds of material admittedly offers a workvitamine requirement of fowls differs from ing basis for the ultimate isolation of the fatthat of mammals. The diet which we used soluble vitamine, and research in this direcfor the successful growth of the chickens con- tion offers many fascinating possibilities. tained an abundance of fat-soluble vitamine, The relation between the vitamine and color however, in the form of carotinoid-free pork in the case of corn may be a genetic one, in liver.

which case it should be possible to transfer Another interesting case of negative rela- the vitamine to white corn. Further attion between carotinoids and fat-soluble tempts, however, to establish an identity of vitamine is seen in the fact that a number of the vitamine with one of the carotinoid pigspecies of animals, such as sheep, swine, dogs, ments is not likely to lead to profitable cats, rats, rabbits, and guinea pigs are free results.

LEROY S. PALMER from carotinoids in blood and adipose tissues, SECTION OF DAIRY CHEMISTRY, and nerve cells. The milk fat of the DIVISION OF AGRICULTURAL BIOCHEMISTRY, mammals of these species is also colorless.

UNIVERSITY OF MINNESOTA How is one to make the successful raising of young on carotinoid-free milk coincide with

SCIENTIFIC ARTICLES the assumption that fat-soluble vitamine is

WOUND HEALING IN EXPERIMENTAL one of the yellow plant pigments ?

(CELLFIBRIN) TISSUE Still another instance of negative relation 1. If we make a defect in the skin, processes between carotinoids and fat-soluble vitamine

of healing set in which in time lead to a is seen in the case of certain vegetable oils, closure of the wound. Primarily, the defect

1J. C. Drummond, Biochem. Jour., XIII., 81, 6 L. S. Palmer and C. H. Eckles, Missouri Agt. 1919.

Exp. Sta. Res. Bull. 10, 361, 1914. 2 L. S. Palmer and H. L. Kempster, Jour. Biol. 6 E. V. McCollum, N. Simmonds and W. Petz, Chem., XXXIX., 299, 1919.

Am. Jour. Physiol., 41, 361, 1916. 3 L. S. Palmer, Jour. Biol. Chem., XXVII., 27, 1 From the Department of Comparative Pathol1916.

ogy, Washington University School of Medicine, 4 D. H. Dolley and Frances Guthrie, SCIENCE, St. Louis and the Marine Biological Laboratory, N. S., L., 190, 1919.

Woods Hole, Mass.

calls forth an emigration of epidermal cells 3. In such experimental “cellfibrin” tissue into the wound. Secondarily, cell prolifera

Secondarily, cell prolifera- the processes of wound healing and tissue tion by mitosis and a contraction of fibrous grafting can be imitated, as far as the pritissue takes place and these three processes mary process in wound healing, namely the contribute to the wound closure. Under cer- formation of layers of regenerating tissue tain conditions the intensity of cell migration through migration, is concerned. A defect in depends upon the size of the wound; and the

this artificial tissue, measuring about 6-8 contraction of the wound, depending in all

square mm. can be closed in the course of two probability on the contraction of the fibrous

to three days, and a piece of tissue grafted tissue and the number of retracting fibers

into a defect can be seen to unite with the being greater in the larger than in the smaller

host tissue through regeneration taking place wound, shows a certain quantitative relation

in the host as well as in the graft. We have to the size of the wound. Essentially and disregarding complicating

every reason to believe that the essential

factors underlying these healing processes in factors, the same stimulus leads to the migra

the skin of a mammal and in such experition of cells and to cell prolification in wound healing. To understand wound healing it is

mental cellfibrin tissue are very similar. In necessary to study experimentally the condi

both cases a tissue which has been in a resttions which influence the migration of the

ing condition is made to migrate into a cells into the wound. The important fact in

wound under the influence of the wound wound healing is that in a tissue which was

stimulus. previously at rest, the making of a defect 4. In order to produce cellfibrin tissue, we calls forth new activities in the cells adjoin

collect in a stender dish a certain quantity of ing the wound.

blood of a large Limulus under conditions 2. In earlier investigations we have shown which preserve the blood cells as much as that after the shedding of the blood of possible. The latter form several layers on Limulus the amobocytes agglutinate and thus the bottom of the dish. The cells are glued to produce a tissue-like organization which under each other as well as to the bottom of the certain experimental conditions bears a cer- dish and thus form a compact even layer of tain resemblance to epithelial, under others to tissue. With a scalpel we can make wounds connective tissue. This agglutination of cells of various sizes in this tissue and then readily is not accompanied by a transformation of follow with a low power of the microscope fibrinogen into fibrin. Subsequently we ob- the different stages of wound healing. At the served that an emigration of cells takes place border of the wound we may recognize the from such tissue if pieces of this “cellfibrin outgrowth of the regenerated tissue even with are put on a slide and kept under suitable

the naked eye. In this defect we can transconditions.4

plant tissue of the same kind and follow the We have recently resumed these experi

union between host and graft. ments, and have succeeded in working out

We may furthermore cut out a very small methods which permit us within certain

piece of tissue, place it on a cover glass, add limits to imitate in an experimental tissue

a drop of blood serum or other fluid, and fix composed of agglutinated blood cells processes

it with vaselin on a hollow slide, in the same which are characteristic of normal tissues.

way as in the case of other tissues growing in 2 A more detailed discussion of these conditions

vitro. We can thus follow the radial outwill be given in a forthcoming paper on wound

growth of the tissue. The pictures obtained healing in the Journal of Medical Research. 3 Leo Loeb, Biological Bulletin, 1903, IV., 301;

correspond closely to those seen in the vitro Virchow's Archiv, 1903, Vol. 173, 35.

culture of other tissues. 4 Leo Loeb, Biochem. Zeitschrift, 1909, XVI.,

5. We have begun an analysis of the con157.

ditions determining wound healing in this

cesses.

experimental cellfibrin tissue; we shall men- certain cells which induce the cells to become tion here a few of the results obtained so far. active and to leave the position in which they (a) The influence of the temperature is

had been at rest. very marked. The temperature coefficient (e) By using our method it is possible to seems to be such as might be expected, if alter experimentally the base on which the wound healing depended upon chemical pro- tissue moves. Thus we can substitute a sur

While regeneration takes place stead- face of paraffin, vaselin, coagulated egg or ily even in the ice chest at a temperature of agar for glass or cellfibrin tissue. It is of from 6–10°, the outgrowth is much more considerable theoretical interest to determine rapid at a temperature of about 20°. Here the character of ameloid movements on subhowever also secondary changes take place stances like paraffin. We find that even on much more rapidly in the outgrowing cells. paraffin and vaselin an excellent outgrowth

(b) The depth of the layer of blood serum of tissue can take place, although the physical covering the wound or piece of cellfibrin properties of these substances modify in some does not seem to influence the rapidity of the respects the behavior of the tissue cells. On healing process. This seems to indicate that coagulated egg and agar outgrowth takes the quantity of oxygen supplied is sufficient, place likewise but secondarily osmotic or even if a layer of serum about 10 mm. deep chemical factors may come into play and separates the tissue from the oxygen of the injure the cells. atmosphere. The amount of free oxygen was (f) We have begun the study of the effect still further diminished in experiments made of various inorganic substances, particularly by Miss Clinton. Hydrogen passed through of constituents of the blood and seawater on the blood serum for one hour previous to the the movement of cellfibrin tissue in wound introduction of the tissue into the serum. healing, and on ameboid movement in genThis was followed by a second period lasting eral, According to their effect on the tissue fifteen minutes in which again hydrogen was movements, we can arrange the various subcarried through the serum. Even under these stances in the following order: (1) 2/3-1/2 conditions outgrowth took place from pieces m NaCl, (2) 2/3-1/2 m KCI, (3) 1/2 m CaCl,, of cellfibrin previously placed on cover glasses. (4) m/3 Na, HPO4, (5) 5/8 m N H.CI, (6)

(c) In a third set of experiments we com- m/3 Na H, P 04, (7) H,O. NaCl is the pared the intensity of tissue movements in least and N H.CI, Na H, P 0.4 and 1,0 are tissue growing in or against the direction of

most injurious. In the latter solutions no gravity. The tissue was held in a vertical distinct outgrowth takes place. How far cerposition on the cover glass. We found that tain variable factors as the amount of blood the tissues can grow out against the direction serum adherent to the tissue or bacterial inof gravity as well or almost as well as in the

fection may modify the results will have to opposite direction. The average intensity of be determined in further experiments. outgrowth is probably somewhat greater in Dilution of the solution within certain the direction of gravity than in the opposite limits is not incompatible with outgrowth. direction.

Thus outgrowth can be readily obtained in a (d) If we observe tissue growing towards solution of 5 c.c. 5/8 m NaCl + 3 c.c. 1,0; ad

H each other from different parts of a wound, dition of as much as 0.5 c.c. of a m/100 HCI or from two separate pieces of cellfibrin placed or NaOH solution to 5 c.c. 5/8 m NaCl likenear each other, we find that the cells coming wise permits frequently the outgrowth of from opposite directions intermingle quito tissue. freely with each other. There is apparently We wish to express our thanks to Mr. no repellent action exerted by one sheet of Julian P. Scott, who assisted us in these tissue upon the movements of the others. It experiments. is evidently not the products of metabolism of

LEO LOEB

2

Bureau of Mines as a result of economic issues brought up during the war. In the present process of manufacture carbon black is made by burning natural gas with a smoky flame against a metal surface and collecting the liberated carbon. The yield is from 2 per cent. to 7 per cent. of the total carbon in the gas. Other possible methods of making carbon black are considered. The uses of carbon black are discussed with particular attention to the ink and rubber industries. Testing methods are described and results of chemical and microscopic analyses of blacks making “long” and “short” inks are given. An explanation for the difference in working qualities of blacks made by different processes is proposed.

THE AMERICAN CHEMICAL SOCIETY.

IV Symposium on annual patent renewal fees with the Division of Pharmaceutical Chemistry and Section of Dye Industry. E. J. PRINDLE, chairman. The symposium discussed various features of the proposal that a system of annual patent renewal fees shall be adopted for the United States. There were verbal or written discussions by: T. H. Anderson, L. H. Baekeland, J. M. Francis, Edwin A. Hill, A. D. Little, John Uri Lloyd, L. V. Redman, Mr. Stinchfield, Elihu Thomson, W. R. Whitney and others, including members of the Patent and Related Legislation Committee of the American Chemical Society, and members of the Patent Committee of the National Research Coun. cil. The chief ideas brought out in this discussion were found in the October, 1919, issue of the Jour. Ind. and Eng. Chemistry.

The use of crystallizers in cane sugar manufacture: CHARLES E. COATES.

The centrifugal method for the rapid determination of potash: L. 8. CONVERSE. For control work, the common methods too long. Description of centrifugal method. Calibration of tubes, effect of speed and time on centrifuge effect of other salts, etc. Comparison of centrifuge and other methods. Usefulness and accuracy of method. It is impossible to obtain results accurate to 0.1 per cent. if the sample contains more than 12 per cent. potassium nitrate. Because of rapidity-20 minutes—it is useful for control work.

Comparison of methods for determining ammonium nitrate: J. T. Grissom. Need of rapid method for estimating ammonium nitrate. Comparison of nitrometer, kjeldahl and formaldehyde methods.

Effects of chlorides on nitrometer determinations of nitrates: M. T. SANDERS. It is not possible to determine nitrates in the presence of larger amounts of chlorides. Determinations with known quantities of chloride are given, results are discussed and reasons for abnormal results suggested. It is impossible to obtain results accurate to 0.1 per cent. if more than 15 to 17 per cent. sodium chloride is present in the dried sample.

The oxidation of methane. Quartz combustion apparatus: F. C. VILBRANDT and JAMES R. WITHROW.

Carbon blackits properties and uses: G. ST. J. PERROTT. An investigation of the carbon black industry has been undertaken by the United States

Adherent rust as an accelerator in the corrosion of iron and steel: W. D. RICHARDSON.

Some properties of commercial silicate of soda: J. G. VAIL.

The leaching of zinc chloride from treated wood: ERNEST BATEMAN. As the result of experimental work and analyses of ties which have seen several years' service, the following conclusions have been drawn: (1) In laboratory experiments as well as service tests the chlorine radical was drawn from the wood by leaching faster than the zinc radical. (2) The amount of each component leached can be calculated with fair accuracy from the diffusion constants of the hydrochloric acid and zinc chloride and the amount of each component present in the solution. (3) From the above it fol. lows that the relative rate of leaching of any other salt from wood can be calculated if we know the amount injected and the diffusion constants of the salt. (4) The presence of comparatively large amounts of zinc in treated material does not insure that the wood is protected against decay unless a sufficient amount of acid be also shown to be present. (5) The basic chlorides of zinc seem to have little or no toxic effect.

Tensile strength of glue: G. HOPP. The paper describes a method for testing glue, by determining its exact tensile strength and elasticity. Hitherto all methods used were more or less arbitrary and entirely comparative. It was shown conclusively that the method is exact and opens a wide field for research and scientific standardization not only of methods of testing glue but also of selecting the right glue for a particular purpose.

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