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It will be worth while, therefore, in these In the case of the individual cyclone, the notes to give the salient features of the phenomena along this line of discontinuity are Bjerknes papers.

about as follows: That part of the line which The Bjerknes Lines of Discontinuity.--The lies in a general easterly direction from the changes of weather which are associated with center of the cyclone is known as the steeringthe passage of HIGHS and lows in the tem- line. South of it the air is moving from the perate zone are found to depend largely upon south; north of it the air is from the east. a line of discontinuity which marks the Along the line the warm southerly air rises boundary between polar and equatorial air. over the denser easterly air. Passing through In an individual cyclone, this line of discon- the center of the cyclone the line extends off tinuity consists of the steering line and the in a southwesterly direction and forms the squall- or wind-shift, line. Considering as western boundary of the warm tongue of large a portion of the northern hemisphere as southerly air, and the eastern front of an adpossible, this line of discontinuity can be vancing wedge of cooler northwesterly air. traced from one storm to another so that This line is known as the squall line, and its there is little doubt that it is continuous passage is frequently accompanied by consideraround the world. North of this line the air able violence, with thunderstorms and someis that which “ has a low temperature for the times tornadoes, but usually with only a latitude, shows great dryness, distinguishes strong blow, a rise of pressure, a drop of temitself by great visibility, and has a prevailing perature, and, of course, a change of wind motion from east and north. On the southern direction. side of the line, the tropical origin of the air It was on the basis of the advance of these is recognized by the corresponding signs-its lines of discontinuity that Mr. Andrus was generally higher temperature, its greater able to predict the path and advise the balhumidity, its haziness and its prevailing loonists to make as little westerly progress as motion from west and south.” This line is possible during the first night, to stay as far called the polar-front line.

east and north as possible, even if it were necSometimes the undulations of the line are essary to disregard the usual practise in balsuch as to cause loops which may represent looning of staying as low as possible to avoid the cutting off from the parent mass, masses expenditure of ballast early in the race. The of warm or cold air depending upon how far winner followed this advice and had landed north or south the tropical or polar air may in Vermont many hours before the others who extend. If the warm air is cut off, the had reached no greater distance than Illinois cyclone decreases in intensity and disappears; and lower Michigan. This fact demonstrates or, in the case of a new outbreak of polar air very clearly that, as Mr. Upson frankly cona new front is formed behind a too far ad- fesses and as Mr. Andrus emphatically states, vanced one; isolated masses of polar air are it was meteorology that won the race. formed at lower latitudes. This is the forma

C. LEROY MEISINGER tion of great anticyclones, which bring good

WASHINGTON, D. C. weather.

SPECIAL ARTICLES
THE CATALYTIC PROPERTIES OF THE

RESPIRATORY METALS1

4 Bjerknes, J., On the Structure of Moving Cyclones, Monthly Weather Review, February, 1919, pp. 95–99; “The Structure of the Atmosphere when Rain is Falling” (abstract), ibid., July, 1920, p. 401; Bjerknes, V., The Meteorology of the Temperate Zone and the General At. mospheric Circulation,” ibid., January, 1921, pp. 1-3; appeared also in Nature (London), June 24, 1920, pp. 522–524.

The more important physical and chemical properties of the respiratory metals-iron, copper, manganese and vanadium-have long

1 Contributions from the Bermuda Biological Station for Research, No. 123.

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been known. Hitherto, however, the evident manganese without altering the activity of points of similarity which these metals pos- “ laccase."? This latter fact sess have not been offered to explain their striking parallel to the replacement of iron singular activity in respiration.

by copper and manganese in certain of the In the first place, as Griffiths has pointed respiratory pigments. But this parallel may out, the atomic weights of these metals differ be pushed still further. When acting upon very slightly from one another: Mn=55; peroxides, these metals are serving in the Cu=53; Fe=55.9; V=51.3 Is such a capacity of catalysts. Now, it is not wholly condition purely accidental, or does it indi- impossible that the respiratory metals serve in cate something concerning the chemical the same way. affinities of the proteins with which these Alsberg and Clarks believe that the copper metals are associated ? It should be noted of hæmocyanin acts as a catalyst for oxygen, also that the valences of the elements in ques- and if this be the case, the oxygen would be tion are variable to an unusual degree (Cu, more readily given off to such acceptors as 1-2; Mn, 2–7; Fe, 2–3; V, 3–5). So marked are present in the tissues, thus making a degree of variation may be without theoret- hæmocyanin in reality analogous to a perical significance, yet it is an interesting coin- oxide-peroxidase system. As for vanadium, cidence. These metals also closely approxi- Hechto holds (on the grounds of the relatively mate one another in specific gravity. In ad- low binding power for oxygen which Winterdition they all form oxides with great facility. stein10 reports for ascidian blood) that vanaBut perhaps the most suggestive property dium, too, probably serves the role of catalyst which they have in common is that of in the blood of tunicates. Also, from the catalysis.

description which Griffiths11 gives of his pinIt is a commonplace of inorganic chemistry naglobin,12 it is not at all impossible that the that minute amounts of iron and of man- manganese of this pigment serves in a simganese hasten many reactions. This is like- ilar capacity. The fact that the metals are wise true of both copper and vanadium. But always present in very small quantities furit is much more significant that these same ther strengthens the catalyst hypothesis. elements also have a very profound catalytic Hæmocyanin, which has a molecular weight effect upon many physiological processes. of 18.762 (Griffiths), has in its molecule only One part of manganese in one million greatly 63.6 gram molecules of copper. Furtheraccelerates the growth rate of Aspergillus more, one should recall that in certain slugniger.4 Moreover, the salts of copper, iron gish animals respiratory pigments are present and manganese serve as powerful catalaysers

which are not associated with any oxidizing for peroxides, and will in some cases replace metals. These have been investigated extenthe enzyme peroxidase. Bertrand believed

sively by Griffiths, 13 and are called by him that his enzyme " laccase" owed its activity achroglobins. An a-achroglobin is found in a to manganese, but it was subsequently shown limpet, Patella vulgata, and a ß-achroglobin by Bach® that iron could take the place of

in chitons. A y-achroblobin was described for 2 “Respiratory Proteids,” London, 1877, p. 60. 7 Bayliss, “Principles of Gen. Physiol.,” 1918, 3 Since Griffith's work, vanadium has been de

London, p. 585. scribed by Henze (1911-12, Zeits. physiol. Chem., 8 Jour. Biol. Chem., 1914, 19, 503. 72, 494; 79, 215) for the blood of ascidians. The

9 Amer. Jour. Physiol., 1918, 40, 165. writer includes it, therefore, with the list of 10 Biochem. Zeits., 1909, 19, 384. Griffiths.

11“Respiratory Proteids,” London, 1897. 4 Bertrand, C. R., Acad. Sci., Paris, 1912, 154, 12 A respiratory protein containing manganese. 381.

It was first isolated from Pinna squamosa, from OC. R. Acad. Sci., Paris, 1897, 124, 1032.

which it derives its name. 6 Chem. Berichte, 1910, 43, 364.

13“ Respiratory Proteids," London, 1897.

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ascidians, but the presence of vanadium in practically equal, in nutritive properties, to association with the proteid escaped Griffith's the unheated raw milk. The pasteurized observation. Whether non-metallic respiratory milk, heated at 145° F. for 30 minutes, propigments represent degeneration, or whether duced scurvy very quickly and all of the they are phylogenetic predecessors of metal- animals died in a very short time. Examinalic pigments, is difficult to decide; but their tion revealed the fact that the pasteurized presence in the animal kingdom shows that milks had been stirred rather violentiy with the function of oxygenation is not dependent motor-driven propellors, while the boiled milk upon the presence of a metal in the pigment had not been stirred mechanically. This led molecule-a fact which gives strong indica- us to believe that oxidation had occurred in tion that the association with metals was the pasteurized milks due to the intimate conoccasioned by the need of a greater capacity tact of air with the milk particles. Conse for ready oxidation and reduction, the need, quently, many new animals have been added that is, of a catalyst.

with the result that we have been able to show John F. FULTON, JR. that the nutritive and antiscorbutic properHARVARD UNIVERSITY

ties of cow's milk are destroyed by oxidation.

Some destruction occurs when air is bubbled THE INFLUENCE OF HEAT AND OXIDATION through milk at 145° F. for 30 minutes, but UPON THE NUTRITIVE AND ANTISCOR

the destruction is much more marked when BUTIC PROPERTIES OF COW'S MILKI

oxygen or hydrogen peroxide is used. OxyIn a recent paper? from the Minnesota Ex- gen and hydrogen peroxide will destroy the periment Station we submitted data which antiscorbutic accessory at room temperature indicated that the nutritive and antiscorbutic although the destructive action is hastened properties of cow's milk are dependent upon as the temperature increases. Milk may be the nature of the feeding materials which pasteurized in closed vessels or boiled in the constitute the dairy ration.

open air without appearing to lose its nutriIn April, 1920, a series of studies was tive and antiscorbutic properties when fed to initiated with the view of ascertaining the in- guinea pigs. When carbon dioxide is bubfluence of heat upon the nutritive properties bled through the milk, it compares very favorand the antiscorbutic potency of milk. The ably in nutritive properties with the raw milk. experimental milk used in these studies was Our work, now in progress, on orange juice obtained from an Ayershire cow fed upon a shows that the antiscorbutic properties are ration composed of the same types of feeding

not destroyed by boiling for 30 minutes. At materials throughout the experimental period. least, if destruction occurs it is not discernBy this method it was hoped that we might

ible with the methods employed. Hydrogen eliminate fluctuations in the vitamine content

peroxide destroys the antiscorbutic factor in of the dairy ration and thereby reduce to a

orange juice at room temperature, and the minimum any variations in the nutritive

speed of the oxidation is hastened as the properties of the milk.

temperature increases. Oxidation would apIn these studies we have used a total of 163

pear to be a more important factor than heatguinea pigs, and control groups were included

ing as far as the nutritive and antiscorbutic in each series. In the first series of experi

properties of milk are concerned. ments it was found that boiled milk was

EDLA V. ANDERSON, 1 Published with the approval of the director as

R. ADAMS DUTCHER, Paper No. 247, of the Journal Series of the Minnesota Agricultural Experiment Station.

C. H. ECKLES, 2 Dutcher, R. A., Eckles, C. H., Dable, C. D.,

J. W. WILBUR
Mead, S. W., and Schaefer, O. G., J. Biol. Chem., MINNESOTA EXPERIMENT STATION,
XLV., 119-132, December, 1920.

UNIVERSITY FARM, ST. PAUL

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Medical School
The Medical School is an Integral part of the University and
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with evidence of a reading knowl- ADMISSION: All students entering the Freshman edge of French and German.

Each class is limited to 90 students, men and women being Class will be required to present credits for two admitted on the same terms. Except in unusual circumstances,

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Chemistry (General and Organic), Physics and Ir vacancies occur, students from other institutions desiring advanced standing may be admitted to the second or third year Biology, with their laboratories, and at least provided they fulall

all of our requirements and present ex. one year in English and one year in a modern ceptional qualifications.

foreign language. INSTRUCTION

COMBINED COURSES: Premedical course of two The academic year begins the Tuesday nearest October 1 and closes the third Tuesday in June. The course of instructon,

years is offered in the College of Arts and occupies four years and especial emphasis is laid upon prao

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second year in the medical course. The charge for tuition is $250 per annum, payable in threo Instalments. There are no extra fees except for rental of microscope, cortain expensive supplies, and laboratory breakage.

School of Pharmacy, School of Dentistry and The annual announcement and application blanks may be Graduate School of Medicine also. obtained by addressing the Dean of the Johns Hopkins Medica School

Women admitted to all Schools of the Washington and Monument Sts. BALTIMORE, M.D

College of Medicine
SUMMER WORK FOR GRADUATES
IN MEDICINE

For bulletins and all other information, addreas Beginning Tuesday, June 6th, and ending Thursday, July 16th, a course in medical diagnosis, including laboratory exer

Tulane College of Medicine cises in clinical pathology and demonstrations in pathological

P. O. Box 770 anatomy, will be offered. Tbe course will be limited to twenty students, fee $100. Applications should be made to the Dean's

New Orleans, La. Office.

Northwestern University

Medical School

Yale University

Situated in Chicago in close proximity to important Hospitals with an abundance of clinical material. Admission Requirements—Two years of College credit

including a satisfactory course in Physics, Chemistry,

Biology or Zoology, and French or German. Course of Study-leading to the degree of Doctor of

Medicine-Four years in the Medical School and a fifth year either as Interne in an approved hospital or devoted to research in some branch of Medical

Science. Graduate Instruction—in courses leading to the degree

of Master of Arts or Doctor of Philosophy. Research Foundation–The James A. Patten Endow

ment for Research affords unusual opportunities for advanced students of Medical Science to pursue

special investigations. Research Fellowship -Four fellowships of the value

of $500 each are awarded annually to promote

scholarly research. Tuition fees—The tuition fee for undergraduato stu.

dents is $180.00 a year.

SCHOOL OF MEDICINE Affiliated with the New Haven Hospital and New Haven Dispensary

109th Session Reorganized on a full-time basis Entrance Requirements: A minimum

of two years (or its equivalent) of college including general biology, physics, general and organic chemistry, physical chemistry or laboratory physics, and either French or German. ALL OF THE GENERAL FACILITIES OF THE UNIVERSITY ARE AVAIL.

ABLE TO MEDICAL STUDENTS As the number admitted to each class is limited, applications must be made before June 15.

For information address

C. W. PATTERSON, Registrar 1421 South Dearborn Street Chicago, Illinois

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Marine Biological Laboratory

Woods Hole, Mass. INVESTIGATION Facilities for research in Zoology,

Embryology, Physiology, and BotEntire Year any. Eighty-four private labora

tories, $100 each for pot over three months. Thirty tables are available for beginners in research who desire to work under the direction of members of the staff. The fee

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Courses of laboratory Instruction

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brate Zoology, Protozoology, Em

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