764 



SCIENCE 



[N. S, Vol. XLII. No. 1091 



Loeb has been appointed to a newly estab- 

 lished chair of comparative pathology in the 

 medical school. The creation of this special 

 research department is made possible by a 

 fund provided for five years by friends of the 

 university for the purpose. The university 

 announces also the appointment of Philip A. 

 Shaffer, Ph.D., as dean, June 3, 1915, and the 

 following promotions: Borden S. Veeder, M.D., 

 to associate professor of pediatrics; Eobert A. 

 Gesell, M.D., to associate in physiology; 

 Philip C. Jeans, M.D., to instructor in pedia- 

 tries. 



Me. W. p. Turner, of Beltsville, Md., has 

 been appointed to the position of extension 

 instructor in animal husbandry at the Massa- 

 chusetts Agricultural College, the position 

 left vacant by the resignation of Mr. G. E. 

 Story, who recently went to the University of 

 Vermont as professor of animal husbandry. 



Dr. Robert Eetzer, formerly of the Uni- 

 versity of Chicago, has accepted the pro- 

 fessorship of anatomy and deanship of the 

 Creighton Medical College, Omaha. Mr. A. J. 

 Key, formerly assistant in anatomy at the 

 Johns Hopkins Medical School, has been made 

 instructor of anatomy. Dr. G. W. Earle, of 

 Tufts College, has been appointed instructor 

 in pathology and director of the clinical labo- 

 ratory. 



Dr. Leonard Eowntree, associate professor 

 of medicine in the Johns Hopkins Medical 

 School, has accepted the position of professor 

 and chief of the department of medicine in 

 the University of Minnesota. 



The changes in the faculty of the engi- 

 neering departments of Brown University 

 for the year 1915-16 are as follows: Professor 

 P. B. Perkins, who was assistant professor of 

 mechanics last year, has been appointed as- 

 sistant professor of applied physics and teaches 

 some of the courses in physics and electrical 

 engineering. Mr. James A. Hall, who was on 

 leave of absence last year and spent the year 

 in the engineering department of the Link 

 Belt Company, Philadelphia, has returned to 

 take up the position of assistant professor of 

 mechanical engineering, having charge of the 



courses in machine design. Mr. Frank 0. 

 Blake has been promoted from assistant in 

 mechanical engineering to instructor. Mr. 

 Thomas C. Shedd, who was instructor in me- 

 chanical engineering last year, has withdrawn 

 from the university to accept a position with 

 the Phoenix Bridge Company. Mr. Eobert P. 

 Field, who was instructor in electrical engi- 

 neering for a period of five years, has re- 

 signed to take up graduate work in physics ,at 

 Harvard University. 



DISCUSSION AND CORRESPONDENCE 



ARTIFICIAL DAYLIGHT 



To THE Editor of Scienoe: In the issue of 

 Science for October 15, 1915, Professor Simon 

 H. Gage discusses a color filter, recently de- 

 vised by Dr. H. P. Gage which produces an 

 artificial daylight when used with the nitrogen- 

 filled tungsten lamp. Under the caption 

 "Artificial Daylight for the Microscope" 

 Professor Gage not only commends highly the 

 use of artificial daylight in microscopy but 

 also refers to its great potential value in the 

 textile and dye industries, in chemistry and in 

 medicine. Inasmuch as Professor Gage ap- 

 parently is not cognizant of the fact that 

 artificial daylight was scientifically achieved 

 several years before the work of Dr. H. P. 

 Gage, that attention was called several years 

 ago to its possible use in microscopy, and for 

 the past several years various daylight units 

 have been on the market, that at present sev- 

 eral thousand daylight units of the types 

 developed by the writer are in daily use, it 

 seemed advisable to give the readers of Scienoe 

 a brief resume of the subject. 



In 1900 Dufton and Gardner^ described a 

 colored glass for accomplishing the desired re- 

 sult and since that time many have worked on 

 the problem. In 1911 Ives and Luckiesh^ 

 described a color filter which produced a suffi- 

 ciently accurate artificial daylight and de- 

 scribed the entire procedure. Quite a number 

 of these units were installed in various fields 



1 British Assn. Report, p. 631, 1900; Jour. Soc. 

 Chem. Ind., Vol. 23, p. 598, 1904. 



^Eleo. World, May 4, 1911; London Ilium. 

 Engr., Vol. 4, p. 394, 1911. 



