9 6 



POPULAR SCIENCE MONTHLY 



The expedition to Peru arrived in 

 Arequippa at the beginning of 1891, 

 and a site for the observatoiy was 

 selected on the crest of a ridge about 

 300 feet above the city. Here was 

 erected an observatory in which there 

 have been carried forward under the 

 direction of Professor Bailey important 

 observations on the southern stars. 



After working in the observatory es- 

 tablished by Professor Lowell in Ari- 

 zona, Professor W. H. Pickering con- 

 cluded that neither dryness nor alti- 

 tude is the important factor affecting 

 the quality of the seeing, and, in order 

 to study the problem further, an ex- 

 pedition to Jamaica was undertaken 

 in 1899, where observations were made 

 at several stations from the sea-level 

 to an altitude of 2,300 feet. In a sec- 

 ond Jamaica expedition the following 

 year a horizontal telescope, with an 

 18-inch mirror and 15-inch lens, was 

 erected at Mandeville. 



Professor Pickering concludes that 

 elevation above the sea-level gives 

 somewhat better definition, especially 

 towards the horizon, and avoids dust 

 and haze. A dry climate has advan- 

 tages in its freedom from dew, cloud 

 and fog, but does not give better defi- 

 nition than one that is moist. A low 

 latitude has three advantages: The 

 definition is better, the bodies to be 

 observed pass near the zenith and a 

 larger portion of the heavens is 

 brought into view. 



THE HANOVER MEETING OF THE 

 AMERICAN ASSOCIATION 



On the invitation of Dartmouth 

 College the American Association for 

 the Advancement of Science will hold 

 a special meeting at Hanover, N. H., 

 from June 29 to July 3. The Amer- 

 ican Physical Society and the Geolog- 

 ical Society of America will meet with 

 the association, and regular programs 

 will be arranged only in physics and 

 in geology. There will, however, be 



public lectures and numerous interest- 

 ing excursions, and those able to at- 

 tend may look forward to a pleasant 

 visit to a typical New England college 

 under the most favorable conditions. 

 The railways offer rates of a fare and 

 a third on the certificate plan, and 

 excellent local arrangements are as- 

 sured for the entertainment of visitors. 

 Many members regret the transfer 

 of the annual meeting of the associa- 

 tion from the summer to the winter. 

 It is certainly true that the large 

 meetings in a city are likely to sacri- 

 fice the social pleasures to business 

 efficiency and to neglect one of the 

 main objects of the association — the 

 diffusion of science. A meeting such 

 as this at Hanover should be attractive 

 to those who wish to meet their col- 

 leagues amid pleasant surroundings, 

 and to those not professionally en- 

 gaged in scientific work but interested 

 in it. Men and women of this class 

 are especially welcomed to the present 

 summer meeting and may feel free to 

 attend without being elected in ad- 

 vance to membership. Those who go 

 are certain to find the meeting both 

 pleasant and useful. 



SCIENTIFIC ITEMS 



We record with regret the deaths of 

 Dr. Heinrich Maschke, professor of 

 mathematics in the University of Chi- 

 cago; of M. Albert de Lapparent, the 

 eminent French geologist; of Dr. K. 

 Mobius, professor of zoology at Berlin, 

 and of Dr. Pierre Jacques Antoine 

 Bechamp, eminent for his researches 

 in organic chemistry. 



The house of representatives con- 

 curring with the senate and by a 

 unanimous vote, has granted an an- 

 nuity for life of $125 a month to the 

 widows of the late Major James Car- 

 roll, surgeon, U. S. army, and the late 

 acting assistant surgeon, Jesse W. 

 Lazear, whose lives were sacrificed in 

 the study of yellow fever in Cuba. 



