264 



SCIENCE. 



[Vol. V., No. 112. 



their price ; and then the system of gas-heating, which 

 is now being agitated, will be introduced into houses, 

 and finally, without doubt, into factories; and thus 

 the system of pouring out immense quantities of 

 smoke into the air of our cities will cease. 



— Dr. Wiese, the German agricultural chemist, re- 

 cently employed by the government to study suitable 

 vegetables for cultivation in the sandy soil of East 

 Prussia, left Berlin for the Cameroon coast during 

 March. The object of his journey is to study the 

 plants of the country, with a view to their cultivation 

 in Germany. 



— During the Austro-Italian war of 1866, in order 

 to protect their ports from the attack of Italian 

 ships, the Aus- 

 trian s placed tor- 

 pedoes in many 

 concentric cir- 

 cles near the 

 mouths of the 

 harbors. Each 

 torpedo had a 

 separate num- 

 ber, and was con- 

 nected by a wire 

 with the room 

 represented in 

 the accompany- 

 ing illustration 

 from La Nature, 

 and each wire 

 had a separately 

 numbered key in 

 this chamber. 

 The building in 

 which the cham- 

 ber was situated 

 was placed on the 



side of a hill, so as to overlook the port. The cham- 

 ber was lighted only by a lens, which had a field cov- 

 ering the harbor. The rays of light coining from 

 outside were then reflected into a prism which directed 

 them down upon an unpolished glass plate placed 

 horizontally upon a table, where an image of the har- 

 bor was formed. The black marks in the figure point 

 out the exact place of each torpedo, and bear num- 

 bers corresponding to those on the keys. An em- 

 ployee watched the plate constantly, and observed 

 every motion of approaching ships. By pressing a 

 button he could at any time explode the correspond- 

 ing torpedo. 



— The municipality of Paris has at last approved 

 the suggestion of a grant of land for the new central 

 laboratory of electricity, to be built out of the profits 

 of the Paris electrical exhibition of 1881. These 

 profits amounted to no less than $65,000. 



— Among recent deaths we note the following : 

 Mr. John Francis Campbell of Islay, in his sixty- 

 fifth year; Mr. Thomas C. Archer, curator of the 

 museum of science and art, Edinburgh ; Mr. Poydes- 

 sau, French engineer, at Panama, Jan. 7; Louis 



AN AUSTRIAN PLAN TOR "WATCHING THE MOVEMENTS OE VESSELS. 



Godard, aeronaut; Rodolphe Meyer-Dur of Zurich, 

 entomologist, March 2, in his seventy-fourth year; 

 Dr. Julius Mii nter, director of the botanic garden 

 of Greifswald, Feb. 2; Dr. J. C. G. Lucae, anatomist 

 and anthropologist, at Frankfort a. -M., Feb. 3; H. W. 

 Blair, assistant in the U. S. coast and geodetic survey, 

 at Nashville, Tenn., Dec. 15. 



— The Dollfus prize of the Entomological society 

 of France was awarded, on Feb. 25, to Mr. Le'on 

 Fairmaire, for his work on the Hemiptera of France. 



— The first number of Mind in nature, which is ' to 

 furnish in a popular manner information regarding 

 psychical questions,' appeared this month. Those 

 who are willing to accept the marvellous on the 



slightest evi- 

 dence will take 

 pleasure in read- 

 ing the article on 

 metaphysics, by 

 Bishop Samuel 

 Fellows, and 

 that on Christian 

 science, by Dr. 

 S.J.Avery. The 

 article on pre- 

 sentiments is of 

 the same uncon- 

 vincing charac- 

 ter. A paper by 

 Oliver J. Lodge, 

 on experiments 

 in though t-tran s- 

 f ere nee, with 

 one or two by Ed- 

 mund Gurney 

 and others, are 

 reprinted from 

 the Proceedings 

 of the English society for psychical research. 



— In No. 180 of the Zoologischer anzeiger there are 

 some interesting notes upon spiders by F. Dahl. He 

 claims that their sight is imperfect, except at very 

 short distances; and, in consequence of this, their 

 sense of touch is so well developed, that, when an 

 object falls into their net, they can tell upon exactly 

 which radius the object has fallen, though to ascer- 

 tain this they must first go to the centre of the web, 

 even though the object may have fallen near their 

 original position. Their smell and hearing are also 

 excellent, the former so much so that they can 

 distinguish odors. The remarkable instinct pos- 

 sessed by the geometrical spiders is shown by the 

 fact that the first web made by the young is perfectly 

 geometrical. That they reflect, is proved by the fact 

 that they despise certain kinds of tough, chitinous 

 insects, which they have unsuccessfully attacked 

 before. This reflection is to be distinguished from 

 the instinctive dread which they have for bee-like 

 flies. 



— Prof. S. P. Langley sailed on Wednesday for 

 England, to lecture before the Royal institution. 



