Lapas attēli


" has a

removal of the acid thus removes the greater would be anticipated, possibly as a result of part of the toxicity. The continued intracel- adsorption. lular production of acid from the reserve of The velocity of the toxic action exhibits a lipoid-bound “mustard” renders the com- high temperature-coefficient similar to that of pound, once it has penetrated the cell, ex- chemical reactions in general. In one experitremely persistent in its action and difficult ment freshly fertilized starfish eggs to counteract.

placed in two portions of the same “mustard” The toxic action of “mustard gas

solution, one (A) kept at 9 to 10°, the other prolonged latency, a fact in accordance with (B) at 21°. From each solution eggs were the above conception. Fertilized starfish eggs transferred to normal sea-water after exposures treated for a few minutes (up to eight min- of 1, 2, 4 and 8 minutes. It was found that utes) with a freshly prepared weak solution an exposure of 24 minutes at 21° had almost of “mustard” continue to cleave for some the same effect in preventing development as hours, at first regularly; later the cleavage be- one of 8 minutes at 9°-10°. All eggs were comes irregular and the eggs break down and killed by 8 minutes' exposure at 21°, while disintegrate. If acid derived from the pro- most survived this exposure at go. The rate gressive hydrolysis of “mustard” contained of toxic action at 9°-10° is thus about one as reserve in the cell-lipoids is chiefly respon- third of that at 21°. This result suggests that sible for the toxic effect, the long latent period cold, in conjunction with the other methods of action is readily understood. An experi- of treatment, may prove to be of service in ment with adult fish (Fundulus) illustrates treating the skin-burns caused by “mustard both the long latent period and the necessity gas," i. e., it indicates that the temperature that the “mustard " should be absorbed by the of the skin should be kept as low as possible living cells while it is still in the intact or during the treatment (e. 9., washing with icenon-hydrolyzed state. Four fish were placed cold kerosene is suggested). in each of the following solutions: (A) Filtered Experiments on the counteraction of the solution of " mustard” kept at room tempera- toxic action by subsequent treatment with ture five days; (B) a similar solution kept weak basic substances which readily penetrate at room temperature one day; (C) the same protoplasm (ammonia, aniline) have not solution as B, but kept at 0° C. and brought yielded very conclusive results. In several to 20° C. one half hour before using; (D) the experiments fertilized eggs exposed to mussame solution kept at 0° C. until immediately tard” solutions for some minutes and then before using.

brought for three or four hours into sea-water Solutions A and B were almost non-toxic; containing a little ammonia n/2000 (NH, in three of the four fish remained alive after sea-water) showed on the whole a more favorfive days in the solution; in C all fish were able development than eggs returned directly living after three hours, three were dead in from the mustard solution to sea-water eighteen hours, and all in twenty-six hours; (i. e., larvæ showed less irregularity and more in D two were dead and a third dying within active ciliary movement). This favorable three hours. The toxicity is thus an inverse effect of ammonia was distinct but somewhat function of the time during which the " slight. In other experiments Arenicola larvæ tard” is undergoing hydrolysis.

treated for some minutes with solutions of While the loss of toxicity of an aqueous aniline in sea-water (of the anæsthetizing con“mustard” solution corresponds roughly with centration, ca. 1/8 saturated), and then exthe decomposition of “mustard” as deter- posed to "mustard” solution, proved distinctly mined by titration, a lag in loss of toxicity at more resistant to its toxic action than the the end of the curve suggests that in those control. This effect is probably to be reextremely dilute solutions the organism takes garded as an example of the general protective up a larger proportion of the poison than or antitoxic action which anæsthetics exhibit

[ocr errors]
[ocr errors]



with this organism. It is possible, however, means of a micro-pipette. The following rethat the basicity of aniline may be favorable; sults were obtained: larvae anæsthetized with alcohols showed some 1. Eggs injected with distilled water quickly degree of protection, but less marked than recover and continue their normal develop with aniline. The after-treatment of poisoned ment. larve with aniline solutions proved ineffective. 2. Eggs injected with a freshly made sat

Treatment with basic substances appears to urated aqueous solution of “mustard gas" us to offer the most promising means of coun- show no immediate injurious effects but subteracting the action of this poison. A sub- sequently are inhibited in their development. stance whose physical properties, solubilities, 3. Eggs injected with a saturated solution and rate of hydrolysis resemble those of which has been allowed to stand at room “mustard," but which yields on hydrolysis a temperature for two hours undergo base, e. g., ammonia, instead of an acid, cytolysis, the immediate destructive effect beought theoretically to counteract the action of ing more marked than that following the in“mustard" within the cell. Such a compound jection of the undecomposed solution. could be introduced into the lungs in the form 4. Eggs injected with an aqueous solution of a spray, or applied to the skin in the usual

of hydrochloric acid of the same strength as manner. High lipoid-solubility or surface- the decomposed gas solution exhibit approxiactivity, favoring rapid penetration of cells, mately the same effect, viz., a more or less would be essential in such a substance. We extended cytolysis. recommend a systematic search for an organic These experiments lend substantial support compound having these properties. Physio- to the view, previously expressed by Marshall logical experimentation with such a compound, and Smith, that mustard gas, in virtue of its if it is obtainable, should in our opinion yield lipoid-solubility, penetrates rapidly into the important results.

cell-interior where it liberates hydrochloric By the use of intravitam staining, and by acid which, in the free state, is relatively inthe injection of aqueous "mustard” solution capable of penetrating the cell. directly into the body of the starfish egg,

R. S. LILLIE, strong evidence was afforded that free acid is

G. H. A. CLOWES, liberated within the cell.

R. CHAMBERS The intravitam stain used was neutral red. THE MARINE BIOLOGICAL LABORATORY, Eggs were treated with solutions of “mustard” Wood's HOLE, Mass. oil (in sea-water) sufficiently concentrated to cause subsequent abnormal development, and

SPECIAL ARTICLES were then transferred to an extremely dilute

ON HERSCHELL'S FRINGES solution of neutral red in sea-water. Normal HERSCHELL's fringes, as produced by the eggs were simultaneously treated with the familiar apparatus consisting of a rightneutral red solution. For a period of at least angled prism reposing with its broad face on half an hour controlled and treated eggs were a plate of obsidian, present the well-known colored to about the same degree. The treated group of achromatic fringes running parallel eggs later became progressively more intensely to the arc or limit of total reflection. Obstained, so that in an hour after the treatment servation is made in a direction normal to the the greater intensity in color of the “gassed” edge of the prism. eggs over that of the control was easily recog- It occurred to me that the phenomenon could nizable.

be made much more striking and of wider The effect of "mustard" and its decomposi- scope, if a long 60°prism were used and obtion-products on the cell-interior was tested servation made in a plane of symmetry parallel by the introduction of a drop of the gas solu- to the edge of the prism. In the interest of tion into the body of the fertilized egg by variety, moreover, it is preferable not to em

[ocr errors]


ploy strictly accurate surfaces; so that the seen by side light, with different patterns in prisms with which grandfather used to dec- the two roof-faces. orate his gas fixtures will, as a rule, suffice The type of interference figure clearly deadmirably. In the figure P is such a prism pends on micrometric differences of the faces (truncated) on a plate of obsidian Q, the in contact. The ellipses are Newton's rings long edges being normal to a white window modified by the color dispersion of the glass. curtain at L near by, illuminated with sun The hyperbolae, however, are about equally light or day light; or any light toward the frequent; but their character is less easily front, overhead, is good.

stated. They probably originate in cylindrics. The rays that are wanted, s, will enter The case of the 45°-90° prism, with the right symmetrically at a mean angle of about 30° to angled faces respectively horizontal (on the the vertical and after reflection at the base plate) and vertical, is also interesting; for of the prism and the plate, reach the eye in the here the ellipses are apt to be circles with each direction E. The rays totally reflected, t, come of the two groups seen after two reflections, from a greater angle to the vertical and are one in each of the orthogonal faces. The not wanted.

light should enter nearly normal to the oblique face. As it leaves in the same way, one should observe through a horizontal slot in a white screen.

I may add a similar observation: If a cylindrical lens (say 1 diopter) is placed on a plate and illuminated with homogeneous light, the interference pattern consists of a succession of equidistant arrow heads along the line of contact, all pointing in its direction. Now these are the very forms observed in the interferences of reversed spectra along the line of coincidence of spectra, except that the latter are apt to be far narrower than the former.

seems therefore, as if the effect of color paThe limit of total reflection here (also riation in one case and of the cylindric ineasily recognized) is usually a sharp parabolic crease of thickness of air film, in the other, or cuspidal apex. The light seen through were formally capable of like treatment. either face enters by the opposed face. On

CARL BARUS looking down from a steeper angle and with BROWN UNIVERSITY, properly selected faces, brilliant groups of

PROVIDENCE, R. I. complete confocal ellipses (major axis one half to over two inches), of confocal hyperbolae may be seen in each of the roof faces. To find advantageous combinations, the three faces of A Weekly Journal devoted to the Advancement of each prism should be examined in succession,

Science, publishing the official notices and proand it is well to rub P on Q to improve the

ceedings of the American Association for

the Advancement of Science contact. On moving the eye fore and aft or using different pressures, any type of ellipse

Published every Friday by with white or colored disc may be produced at

THE SCIENCE PRESS pleasure. It is usually preferable to use a shorter plate Q than is given in the figure, LANCASTER, PA. GARRISON, N. Y. about one half the length of the prism.

NEW YORK, N. Y. When well produced the ellipses may also be Entered in the post-office at Lancaster, Pa., us recond class meiller




Cornell University
Medical College

Washington University

School of Medicine



Candidates for entrance are required to have completed at least two full years of college work which must include English, German, and instruction with laboratory work in Physics, Chemistry and Biology.

Admits graduates of approved Colleges

presenting the required Physics, Chem

istry and Biology.
Instruction by laboratory met bods

throughout the course. Small sections
facilitate personal contact of student

and instructor.
Graduate Courses leading to A.M. and

Ph.D., also offered under direction of
the Graduate School of Cornell Uni-

Applications for admission are preferably

made not later than June.

INSTRUCTION Instruction begins on the last Thursday in September and ends on the second Thursday in June. Clinical instruction is given in the Barnes Hospital and the St. Louis Children's Hos Dital, affiliated with the medical ookool, the St. Louis City Hoc pital, and in the Washington University Dispensary. COURSES LEADING TO ACADEMIC

DEGREES Students who have taken their premedical work in Wash. ington University, are eligible for the degree of B.S. upon the completion of the first two years of medical work.

Students in Washington University may pursue study in the fundamental medical sciences leading to the degree of A.M. and Ph.D.

TUITION The tuition fee for undergradusta medical students in M800 per ARB m. Women are admitted.

The catalogue of the Medical School and other information may be obtained by application to the Dean.

For further information and catalogue address
The Dean, Cornell University

Medical College

Department B
First Avenue and 28th St. NEW YORK CITY

Euclid Avenue and Kingshighway St. Louis

Tulane University of Louisiana

Johns Hopkins University

COLLEGE OF MEDICINE Medical School The Medical School is an Integral Part of the University and

(Established in 1834) is in close Affiliation with the Johns Hopkins Hospital

Candidates for admission must be graduates of approved

School of Medicinecolleges or scientific schools with at least one year's instruction,

After January 1 1918, all students entering the including laboratory work, in physics, chemistry, and biology Freshman Class will be required to present credits and with evidence of a reading knowledge of French and German.

for two years of college work, which must include Each class is limited to 90 students, men and women being

Biology, Chemistry and Physics, with their laboraadmitted on the same terms. Except in unusual circumstances, tories, and one year in German or French. applications for admission will noć be considered after July 1st. I vacancies occur, students from other institutions desiring

Graduate School of Medicine advanced standing may be admitted to the second or third year, A school for physicians desiring practical clinical proviảed they fulfill all of our requirements and present ex- opportunities, review, laboratory technic or cada ceptional qualifications.

veric work in surgery or gynecology. Excellent INSTRUCTION

facilities offered in all special branches. The rost academic year bogins Soptember 30, 1919 and School of Pharmacydovou on the second Tuesday in Juno. The course of instruo

Admission: Three years of high school work, or non occupies four year, and cspecial emphasis is laid upon practical work in the laboratories in the wards of the Hospital

12 units. Two years for Ph.G. degree. Three and in the Dispengary.

years for Ph.C. degree.

School of Dentistry-

Admission: Four years of high school work, with The charge for tuition is $200 per annum, payable in three instalments. There are no extra fees except for rental of micro

15 units. Thorough, practical, as well as comprescope, certain expensive supplies, and laboratory breakage.

hensive technical training in dentistry.

Women admitted to all Schools on the same terms

as men. The annual anaouncement, application blanks, and circular desoribing graduate courses may be obtained by addressing the

For catalogs and all other information, address Dean of the Johns Hopkins Medical School Waeblogton and Monument Sro. BALTIMORE, MD. TULANE COLLEGE OF MEDICINE

P. O. Box 770, New Orleans, La.

1765 School of Medicine of the University of Pennsylvania 1919

The Ono Hundred Fifty-third Annual Session of this institution opened September 27, 1918, and continues

until June 18, 1919. The First and Second Year Classes are ordinarily limited to 100 students; during the period of the war this limitation will not be strictly enforced. Application for admission should be in the hands of the Dean before July 1st.

REQUIREMENTS FOR ADMISSION: Candidates must have successfully completed the work prescribed for the Freshman and Sophomore Classes in colleges recognized by this University, which must include at least one year of collego work in Physics, Gonoral Biology or Zoology and Chemistry (Qualitative Analysis is required; Organic Chemistry is recommended, and in 1919 will be required), together with appropriate laboratory exercises in each of these subjecta, and either French or German of more than slementary grade. For detailed information send for catalogue.

UNDERGRADUATE COURSE: The course of instruction extends over four annual sessions, the work 80 graded that the first and socond years are largely occupied by the fundamental medicals ubjeoto. The third and fourth year aro largely devoted to the practical branches, prominence being given to clinical instruction, and the classes sub-divided into small groups so that the individual students are brought into particularly close and personal relations with the instructor and with the pationts at the bedside and in the operating room. After graduation further hospital work is undertaken by the members of the class; and more than 90 per cent. attain by competitive examination or by appointment positions as internes in hospitals in this city or elsewhere. The Pennsylvania Bureau of Medical Education and Licensure requires of applicants for license a year spent in an approved hospital.

POST GRADUATE WORK: (1) Any graduate possessing a baccalaureate degree may pursue work in Anatomy, Physiology, Physiological Chemistry, Bacteriology, Pathology, Pharmacology, Research Medicine and Mental Discasos with view of obtaining the higher degrees of Master of Arts or Scienco and of Doctor of Philosophy in the Graduato School of the University. For information address Dean of Graduate School, University of Pennsylvania.

(2) Courses in Public Hygiene (inaugurated in 1906) leading to diploma (Doctor of Publio Hygieno, Dr. P.H.), are open to graduates in medicine who have had a preliminary education similar to that required for admission to the Medical School. The subjects comprebended in the course aro: Bacteriology, Medical Protozoology and Entomology, Metso zoan Parasitology Chemistry,

Sanitary Engineering, Sanitary Architecture, Meat and Milk Inspection, School Inspeo tion, Vital Statistics, Sanitary Legislation, and Personal and General Hygiene. The full

course extends over one academic year. Special subjects in the course may be takon by any ono possessing muitable preliminary qualifications. For details address Director of Laboratory of Hygieno.

(3) From the opening of each term to about February 1 courses in Tropical Medicine are open to graduates in Medidne, comprehending instruction in Medical Climatology and Geography, Hygiene of Tropics and of_Bhips, Tropical Medioine, Bacteriology, Protozoology, Entomology, Helminthology, and General Medical Zoologs, Pathology, Sido Diseases, Eyo Diseases, and Surgery of Tropical Affections.

(4) During the academio session special courses in any of the branches of tho modical curriculum are open to grado uates of this or other regular schools of Medicino, both in tho clinical subjects and in laboratory studies. Tho excellent hospital facilities offered by the University Hospital, tho neighboring Philadelphia General Hospital and other institu. tions with which the members of the staff of instruction are connected, guarantee exceptional opportunities for clinical oboorvation.

TUITION FEE: Undergraduate study, $200 annually ; fees for special courses on application. For detailed infor mation or catalogue address

DEAN OF SCHOOL OF MEDICINE University of Pennsylvania

Philadelphia, Pa.

University of Georgia

University of Alabama


Augusta, Georgia

School of Medicine

Mobile, Alabama Entrance Requirements The satisfactory completion of two years of study, in an institution of collegiate grade, to include Biology, Chemistry, Physics, and a reading knowledge of French or German. In addition to four year High School diploma.

Combined Course The Combined Course which is now offered by the University in connection with its Medical Department gives to the student the opportunity of obtaining the B.S. and M.D. degrees in six years.

This course is recommended to all intending students.

The equipment of the schoolis complete. The clinical facilities ample. Eight full time teachers.

For catalog and any desired information,
Tucker H. Frazer, M.D., Dean

School of Medicine
St. Anthony and Lawrence Sts.,


ENTRANCE REQUIREMENTS The successful completion of at least two years of work including English, Physics, Chemistry, and Biology in an approved college. This in addition to four years of high school.

INSTRUCTION The course of instruction ocoupies four years, begin ning the second week in September and ending the first week in June. The first two years are devoted to the fundamental sciences, and tho third and fourth to practical clinic instruction in medicine and surgery. All the organised medical and surgical charities of the oity of Augusta and Richmond County, including the hospitals, are under the entiro control of the Board of Trustees of the University. This agreement affords a large number and variety of patients which are used in tho clinical teaching. Especial emphasis is laid upon practical work both in the laboratory and clinical de partments

TUITION Tho charge for tuition is $150.00 a year except for residents of the State of Georgia, to whom tuition is freo. For further information and cataloguo address

The Medical Department, University of Georgia


« iepriekšējāTurpināt »