June 24, 1910] 



SCIENCE 



987 



Dr. Walter M. Mitchell, of Philadelphia, 

 has been appointed assistant professor of as- 

 tronomy in the University of Michigan. 



Professor L. S. Griswold has resigned the 

 chair of geology at the Missouri School of 

 Mines, to give his entire time to consulting 

 work. Professor Guy Henry Cox, formerly 

 assistant professor of mineralogy and petrog- 

 raphy, has been placed in charge of the depart- 

 ment of geology and mineralogy. Mr. J. W. 

 Eggleston has been appointed assistant pro- 

 fessor of geology and mineralogy. He is a 

 graduate of Amherst and of Harvard and has 

 taught geology and mineralogy in the Colo- • 

 rado School of Mines and Harvard University. 



The following changes occur this year in 

 the biological department of the North Caro- 

 lina College of Agricultural and Mechanical 

 Arts and Experiment Station. Mr. P. L. 

 Gainey, assistant soil bacteriologist, resigns to 

 accept a fellowship in the Shaw School of 

 Botany. Mr. B. B. Higgins, assistant bot- 

 anist, resigns to accept the position as assist- 

 ant in Cornell University. Mr. T. B. Stansel 

 is appointed as assistant in soil bacteriology 

 (experiment station). Mr. Warren C. Norton 

 is appointed as assistant in botany (college). 



Dr. Lawrence I. Hewes has been appointed 

 assistant professor of mathematics at Whit- 

 man College. 



Maurice L. Dolt, instructor in industrial 

 chemistry at Lehigh University, has been ap- 

 pointed assistant professor at the University 

 of North Dakota. 



Mr. J. W. Mavor, A.m. (Harvard), has been 

 appointed instructor of zoology at Syracuse 

 University. 



Dr. L. Aschofp, professor of pathology at 

 Freiburg, has been called to Wiirzburg. 



DISCUSSION AND CORRESPONDENCE 



^' water vapor on mars 

 To the Editor op Science: I venture to 

 hope that you will regard the following com- 

 munications as of interest to your readers. 

 C. G. Abbot 

 Astrophysical Obsebvatoey, 

 Smithsonian Institdtiok 



Lowell Observatory 

 Supplement to Bulletin No. 4.3 

 Quotation from C. G. Abbot, " A Shelter for 

 Observers on Mount Whitney," Smithsonian Mis- 

 cellaneous Collections, Quarterly Issue, Vol. 5, 

 Part 4 (p. 506): "The observations of Director 

 Campbell on the spectrum of Mars were entirely 

 conclusive in showing that water vapor, if present 

 at all in the atmosphere of Mars, is in less quan- 

 tity than is contained in the extremely rare and 

 dry part of the earth's atmosphere which is above 

 Mount Whitney. In fact, no evidence at all of 

 water-vapor on Mars was detected oy Campbell." 



" Unfortunately, both Director Campbell and 

 myself were on Mount Whitney during unusually 

 unfavorable weather, for the whole southwest, 

 including northern Mexico, was just at that time 

 visited by floods of rain and cloudy weather. 

 Such a condition would not probably be met 

 with at that season one year in ten." 



This admission speaks for itself. The excessive 

 moisture must have pervaded the air generally 

 to the masking of moisture on Mars. Even 

 ordinarily summer is the most unfavorable time 

 for getting any results, because the earth's mois- 

 ture is then at a maximum. 



Smithsonian Institution 



Washington, D. C, 



March 24, 1910. 

 Dear Sir: I have read Lowell Observatory Sup- 

 plement to Bulletin No. 43. The supplement is 

 unsigned and I do not know but it may have 

 escaped your endorsement. I wish its author 

 might have added in fairness the following facts 

 given in Lick Observatory Bulletin No. 169, viz.. 

 Professor Campbell made spectrograms No. 1 and 

 No. 2 on September 1, between 10" 30"" and 15" 

 Pae. St. time. Of spectrogram No. 1 he says, 

 "Little a shows plainly but very faintly in the 

 Martian and both lunar spectra; less intensely 

 than on No. 3 and more strongly than on No. 2; 

 essentially equal in Mars and moon, and certainly 

 not perceptibly stronger in ilars than in the 

 moon." Of spectrogram No. 2, he says, " In the 

 Martian spectrum o is difficult to see; if we were 

 examining this Martian spectrum as an unknown 

 spectrum, we should almost certainly pass over 

 the a band ivithoiot suspecting its existeiioe." 

 Professor McAdie's sling psyehometer was read 

 on Mt. Whitney at 9" 00", U" 30", 12'' 30" and 



