288 



THE POPULAR SCIENCE MONTHLY. 



information concerning the red sunsets and 

 the diffusion of volcanic dust, which had not 

 yet been examined ; and he could only say 

 that nothing had yet appeared which was 

 inconsistent with the Krakatoa theory. 



Dr. Lenz, of St. Petersburg, has devised 

 a telephone for measuring temperatures at 

 a distance. Suppose two stations, A and B, 

 joined by two wires of iron and silver which 

 are soldered at both ends. If the solder- 

 ings differ in temperature, a thermo-electric 

 current will circulate through the wires, and 

 may be made to express itself by means of 

 a telephonic apparatus ; but if the observer, 

 say at A, raises or reduces the temperature 

 of the soldering at his end, till it is identi- 

 cal with the temperature at the end B, the 

 telephone will cease to speak. 



OBITUARY NOTES. 



M. J. A. Barral, a distinguished French 

 chemist and agronomist, died m September, 

 in the sixty-sixth year of his age. He was 

 Professor of Physics in the College of Sainte- 

 Barbe. In 1850 he made an experimental 

 balloon ascension with M. Bixio, to test the 

 temperature and moisture of the air at dif- 

 ferent elevations. He founded the " Journal 

 de I'Agriculture," and was commissioned by 

 Arago editor of his works, which were pub- 

 lished in seventeen volumes. 



Professor J. C. Schioedte, a prominent 

 Danish entomologist and editor of the "Na- 

 turhistorisk Tidskrift," of Copenhagen, is 

 dead, at the age of sixty-nine years. 



Mr. Charles Manbt, engineer, who re- 

 cently died in England, was for seventeen 

 years paid secretary and for twenty-eight 

 years honorary secretary of the Institution 

 for Civil Engineers. He was the son of 

 Aaron Manby, an eminent iron-manufact- 

 urer, and was engaged in the construction 

 of the first pair of marine engines with os- 

 cillating cylinders and upon the building of 

 the Aaron" Manby, the first iron steamship 

 that ever made a sea-voyage. 



Barok Paul Thenard, the eminent 

 French agricultural chemist, has recently 

 died, in the sixty-fifth year of his age. Ho 

 was a man of immense wealth, and em- 

 ployed it in the service of science. He was 

 the author of investigations on phosphuret- 

 ed hydrogen, the action of the electric spark 

 in chemical combinations, and on numerous 

 questions in agricultural chemistry ; and he 

 possessed extensive laboratories at Talmay 

 and in Paris. 



Mr. George Bentham, F. R. S., an emi- 

 nent English botanist, died on the 10th of 

 September last, in the eighty-fourth year of 

 his age. He was a son of General Samuel 



(afterward Sir Samuel) Bentham, and a neph- 

 ew of Jeremy Bentham, the famous econo- 

 mist. His attention was attracted to bot- 

 any, while the family were living in France, 

 by the perusal of De Candolle's "Flore 

 Fran9aise," and he immediately took to the 

 study of the flowers in the back yard. His 

 studies were afterward of a more diversified 

 character, while botany still led, till 1829, 

 when he gave up the profession of the law 

 for his favorite science. He studied the 

 enormous collections of the East India Com- 

 pany which had been brought home by Wal- 

 lich from India ; worked out the flora of 

 Hong-Kong and Australia, the latter in sev- 

 en volumes, containing seven thousand spe- 

 cies, for the Royal Gardens at Kew ; re- 

 vised the orders of the Labiatce, Sa-ophu- 

 larince, Foli/ffonece, etc. ; and composed, in 

 association'with Hooker, the " Genera Plan- 

 tarum," a complete general work on the 

 phanerogamic plants, which was completed 

 in the spring of 1883. "He has left no 

 equal," says "Nature," " except Asa Gray." 



Dr. Joseph Anton Maximilian Perty, 

 Professor of Zoology ,Psychology, and An- 

 thropology in the University of Berne, died 

 on the 8th of August last, aged eighty years. 

 He was a man of great literary activity in 

 the fields of natural history and metaphys- 

 ics. Among his works in the latter field 

 were "A Universal Natural History," in 

 four volumes, a treatise on the smallest 

 forms of life, an introduction to the natural 

 sciences, a text-book of zoology, outlines of 

 ethnology, and books on anthropology and 

 psychology. 



The death of Dr. Heinrich Schellen, 

 author of two well-known works on the elec- 

 tro-magnetic telegraph and spectrum analy- 

 sis, is reported. Dr. Schellen was formerly 

 director of the Cologne Realschule, and, be- 

 sides the works named above, published an 

 arithmetic, a German version of Padre Sec- 

 chi's book on the sun, and other works on 

 physical subjects. He was sixty-six years 

 old. 



M. Eugene Bourdon, inventor of the 

 metallic barometer and manometer which 

 are largely used, died in Paris on the 29th 

 of September, aged seventy -six years. 



Dr. Settari, an eminent entomologist 

 (particularly in the department of Lepidop- 

 tera), has recently died at Meran, Tyrol. 



Professor Jakob Natanson, a Polish 

 chemist, died in Warsaw, September 16th. 

 He wrote many scientific books in the Po- 

 lish language, the most valuable of which 

 were a text-book on chemistry and a trea- 

 tise on organic chemistry ; prepared carba- 

 mide synthetically in 1856 ; and improved 

 the methods for determining the density of 

 vapors. 



