432 



POPULAR SCIENCE MONTHLY. 



widely diffused and employed in preserving 

 the memory of treaties of peace and alliance, 

 established institutions working well, and a 

 good degree of generally diffused comfort. 



NOTES. 



THE summer courses of the Massachusetts 

 Institute of Technology, beginning at differ- 

 ent dates in June and generally continuing 

 through July, are intended for the benefit of 

 students who wish to prolong their stay hi 

 summer or to make up deficiencies, and are 

 open to persons not students in the institute 

 if they possess the necessary qualifications. 

 The subjects are in the departments of me- 

 chanical drawing and descriptive geometry, 

 mathematics, architecture, chemistry, biol- 

 ogy, physics, European history, French and 

 German, mechanism, and shop work; and 

 provision is made for other (non-technical) 

 subjects for those interested in them. 



THE International Exposition to be held 

 at Brussels this year will include an Inter- 

 national Section of Sciences, divided into 

 the seven Sections of Mathematics and As- 

 tronomy, Physics, Chemistry, Geology and 

 Geography, Biology, Anthropology, and 

 Bibliography. Various privileges will be 

 granted to participants, who will have to 

 pay nothing for their places, and will be 

 allowed rebates on railroads. A series of 

 questions have been prepared by the Belgian 

 Government, on which prizes will be awarded 

 for the best solutions. The prizes appertain- 

 ing to the Section of Sciences are valued at 

 four thousand dollars. Programmes contain 

 lull information on this subject by address- 

 ing the Commissariat General of the Gov- 

 ernment, 17 rue de la Purse, Brussels. 



THE Division of Entomology of the 

 United States Department of Agriculture is 

 engaged in a special investigation of the in- 

 sects that infest stored crops. The list in- 

 cludes the insect enemies of stored grain, 

 flour and meal, fruits, nuts and seeds, herbs 

 and dried plants, drugs, leather, specimens 

 of natural history, etc. Information is in- 

 vited from citizens who have made observa- 

 tions in the matter, particularly from per- 

 sons residing in the South. Special attention 

 is directed to the use of bisulphide of car- 

 bon, applied as a vapor to pervade the 

 stored material. 



GRANITE, wood, and asphalt being accept- 

 ed as the best materials for carriage-way 

 pavements in large cities, preference between 

 them should be, Mr. L. H. Isaacs, C. E., says, 

 in the order, on the score of public hygiene : 

 asphalt absolutely, granite, wood; of noise- 

 lessness, wood, asphalt, granite ; of safety to 

 horses, wood, asphalt, granite ; of cleaning, 

 asphalt, wood, granite ; of economy, granite, 

 wood, asphalt; of facility in repairing, as- 



phalt, wood, granite ; and of convenience in 

 connection with tramway rails, granite, wood, 

 asphalt. 



ALVAN H. CLARK, the famous maker of 

 telescopic lenses, died of apoplexy at his home 

 in Cambridge, Mass., June 9th. He succeeded 

 his father, Alvan Clark, whose fame as a lens 

 maker was equally world-wide, as head of the 

 firm on the death of the latter in 1887. Of 

 his make were the twenty-six inch lens in the 

 Naval Observatory at Washington, and the 

 thirty-inch refractor for the Imperial Ob- 

 servatory at St. Petersburg, for which he was 

 decorated by the Czar ; the great lens of the 

 Lick Observatory ; and the lens for the Yerkes 

 Observatory, Chicago, forty inches in diame- 

 ter, and having a focal length of sixty four 

 feet, which was completed and shipped only 

 a short time before his death. As an as- 

 tronomer he accompanied the total-eclipse 

 expedition to Jerez, Spain, in 1870, and the 

 similar expedition to Wyoming in 1878 ; and 

 discovered fourteen double stars, including 

 the companion to Sirius for which he re- 

 ceived the Leland gold medal from the French 

 Academy of Sciences. 



DR. TRAILL GREEN, Emeritus Professor of 

 Chemistry in Lafayette College, died at Eas- 

 ton, Pa., April 29th, aged eighty-four years. 

 He became a professor in Lafayette College 

 sixty years ago ; was dean of its scientific de- 

 partment and founder of its astronomical ob- 

 servatory ; was one of the original members 

 of the American Association ; was first Presi- 

 dent of the American Academy of Medicine ; 

 and was author of a work on the Floral and 

 Zoological Distribution of the United States. 



MR. J. THEODORE BENT, explorer, classi- 

 cist, and archaeologist, died in London, May 

 6th, of malarial fever contracted in a journey 

 in Sokotra and southern Arabia from which 

 he had just returned with Mrs. Bent fol- 

 lowed by pneumonia. He had spent the 

 winters of several years in journeys of re- 

 search, the fruits of which he recorded in 

 valuable and interesting books. Among the 

 subjects that engaged his attention were the 

 archaeology, classic survivals, and customs of 

 Greece ; the Bahrein Islands of the Persian 

 Gulf ; the Arabian states ; Abyssinia ; and 

 Mashonaland, where he was the first to make 

 a systematic exploration of the ruins of Zim- 

 babwe. His papers before the Royal Geo- 

 graphical Society, the British Association, 

 etc., were of high merit, and his collections 

 had unique value. 



THE Due d'Aumale, who died from the 

 effects of the shock occasioned by the ter- 

 rible disaster at the Charity Bazaar in Paris, 

 was a member of the French Academy, and 

 was distinguished throughout the scientific 

 world for his gift to the Institute of France, 

 in trust for the nation, in 1884, of the Cha- 

 teau of Chantilly for a museum, with the 

 forest and estates for its maintenance. 



