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THE POPULAR SCIENCE MONTHLY. 



Louis Palmieri, Professor of Physics 

 in the University of Naples and Director of 

 the Seismological Observatory on Mount Ve- 

 suvius, has recently died, at the age of sev- 

 enty-five years. He was appointed to the 

 two posts in connection with which he has 

 gained scientiiic renown in 1854, and has 

 since pursued the study of earthquakes and 

 the phenomena associated with them, with a 

 real devotion. lie was the inventor of an 

 electro-magnetic seismograph, by which the 

 most delicate indications of subterranean 

 action could be detected. 



M. Potel has recently submitted to the 

 French Society of Encouragement a new 

 substance, which he has named, after him- 

 self, " poteline," and which appears to be 

 susceptible of numerous applications. It is 

 a mixture of gelatine, glycerine, and tannin, 

 and is, according to the inventor, absolutely 

 impermeable to the air. When warmed, it 

 becomes liquid, or nearly so, and takes all 

 the contours of an object. M. Potel has 

 made corks of it, which form an economical 

 substitute for metallic capsules, and secure 

 an hermetic closing. lie has used it as a 

 coating to preserve meat. At a temperature 

 of 112, it envelops the meat, kills the 

 genus of putrefaction, and prevents any 

 new germ passing in. According to M. 

 Potel, meat thus treated will retain all its 

 freshness for two months. 



According to the experiments of M. 

 Demarcay, the metals which are generally 

 regarded as fixed, even iron, give out real 

 vapors at relatively low temperatures. Cad- 

 mium, for example, volatilizes at 25*7 and 

 zinc at 302. Magnesia had already been 

 found to be volatile below a red heat, when 

 acted upon by water and chloride of silicon. 



With the aid of M. Lippman's electrom- 

 eter, M. Trousseau has succeeded in meas- 

 uring the electrical conductibility of the 

 poorer conductors, particularly of glass. 

 Common glass is very perceptibly conduct- 

 ive, Bohemian glass is less so, while cut- 

 glass has no sensible conducting powers. 

 M. Dumas regards this classification as re- 

 peating from the electrical point of view the 

 one which he has established as dependent 

 on the presence of alkaline salts in the 

 vitreous mass ; of which cut-glass has none, 

 Bohemian glass very little, and common glass 

 a considerable quantity. 



Admiral Count Feodor Petrovitch 

 Lutke, founder of the Russian Geograph- 

 ical Society and President of the St. Peters- 

 burg Academy of Sciences, died in August 

 last. His name is identified to a considerable 

 extent with the history of Russian polar and 

 exploring expeditions, and with the discov- 

 ery of some island groups in the Pacific. 

 He had published narratives of his Arctic 

 expeditions and of a voyage round the world. 



The fact that an aniline black can be 

 formed with vanadium has provoked inves- 

 tigation into the feasibility of the produc- 

 tion of that metal for commerce. MM. 

 Osmond and G. AVitz have found a consid- 

 erable source of supply in the foundrj--sco- 

 rias of Creuzot, France, which contain two 

 per cent of vanadic acid. The scorias have 

 only to be treated with hydrochloric acid to 

 obtain from them a green liquor which can 

 be used directly in dyeing. 



It has been urged against the theoretical 

 importance of the agency of insects in fer- 

 tilizing flowers, that the insects relied upon 

 are rare upon mountain-heights, where the 

 flowers that should be fertilized by them 

 are still abundant. The observations of 

 M. Ch. Musset, of Grenoble, France, which 

 range up to 10,000 feet in height, tend 

 greatly to break the force of this objection. 

 He finds that all the orders of insects are 

 represented to the height of T,400 feet, and 

 that the number of nectar-seeking insects is 

 proportionate to the number of flowers. The 

 hours of wakefulness and of sleep of the 

 nyctitropic flowers the number of which is 

 greater than is supposed and those of the 

 insects are synchronous. The apparent num- 

 ber of nectar-seeking insects, also, is related 

 to the number of their favorite flowers. 



JoriANNES Theodor Eeinhart, Professor 

 of Zoology at the University of Copenhagen, 

 and Inspector of theNatural History Museum 

 of that city, died October 23d, aged sixty-six. 

 He was eminent in ornithology, and was au- 

 thor of a memoir on the birds of the Cam- 

 pos of Brazil, and of numerous papers in the 

 scientific periodicals of Copenhagen. 



M. Bergeron has produced imitations of 

 the forms of lunar craters, by turning a 

 current of gas into a melted metallic mass 

 at the moment when solidification is about 

 to begin. He obtained exact representations 

 of the different varieties of hollows shown 

 upon the moon by using different metallic 

 mixtures. 



Professor Sollas, of Bristol, has pro- 

 posed to the British Association a scheme 

 for securing a complete record of published 

 scientific work, the essential feature of which 

 is, that each nation furnish a record of its 

 own work and of that only, and exchange 

 with all other nations for their records. 

 National committees are to attend to the 

 preparation of the records, the transmission 

 of exchanges, the translating and the com- 

 position of the records into a single work, 

 and an International Congress is to take care 

 of the uniformity and the successful work- 

 ing out of the scheme. 



TnE death is announced, at forty-three 

 years of age, of M. Georges Leclanche, the 

 inventor of the oxide of manganese constant 

 elements. 



