August 22, 1884.] 



SCIENCE. 



155 



rarely or never be made rigorous. Glaciers vary in 

 their characteristics like other groups of phenomena. 

 While those features which characterize them are 

 present, there is no difficulty of recognition; but ex- 

 ceptional cases arise in which a portion only of the 

 diagnostic features are present, and persons who 

 desire extreme precision of language are then com- 

 pelled to hesitate. The difficulty is probably best 

 met by the use of qualifying terms. 



NOTES AND NEWS. 



Fellows of the American association for the 

 advancement of science, who may desire to avail 

 themselves of the privileges of honorary membership 

 of the British association, and to attend the Montreal 

 meeting, will be furnished with the usual ' travelling 

 certificates ' on application to Mr. J. D. Crawford, 

 post-office box 147, Montreal, Canada. These cer- 

 tificates should enable the fellow to purchase convey- 

 ance for himself to and from Montreal at reduced 

 rates. 



— In regard to the phosphorescence of jelly-fish, 

 R. Meldola writes to Nature, that the conclusions 

 arrived at by Mr. Yerrill (Science, July 4, p. 8) can- 

 not fail to be of interest to all who have ever specu- 

 lated on the significance of the luminosity displayed 

 by so many Acalephae, Medusae, and other marine 

 organisms. When in the tropics, in 1875, very simi- 

 lar ideas occurred to Mr. Meldola; and in an address 

 on the phenomena of cyclical propagation, delivered 

 to the Essex field-club on Jan. 28, 1882, he ventured to 

 put forward the following views: " It was in the Bay 

 of Bengal, when on the eclipse expedition of 1875, 

 that I first saw shoals of Medusae in their full splen- 

 dor. Speculating on the meaning of the vivid colors 

 and brilliant phosphorescence of these creatures, I 

 came to the conclusion that both these characters 

 might be protective danger-signals of the same na- 

 ture, and fulfilling the same function, as the bright 

 colors of distasteful caterpillars according to Wal- 

 lace's well-known theory, or the phosphorescence of 

 the Lampyridae according to Thomas Belt ('Natural- 

 ist in Nicaragua,' p. 320). The ' urticating ' powers of 

 the jelly-fish would certainly make them unpleasant, 

 if not absolutely dangerous to predatory fish, and 

 their bright colors and luminosity at night may thus 

 be true warning characters." 



— A joint convention was recently held by the 

 council and past presidents of the British institutions 

 of civil engineers, mechanical engineers, and naval 

 architects, and of the Iron and steel institute, and 

 the Society of telegraph engineers and electricians, 

 to take steps toward the erection of a memorial to 

 the late Sir William Siemens. At a meeting held 

 on June 28, it was reported that the authorities of 

 Westminster Abbey would be pleased to permit the 

 introduction of a memorial window in honor of the 

 distinguished physicist and engineer. The cost was 

 estimated at from seven hundred to eight hundred 

 pounds. The proposal was accepted; and it was 

 decided to limit subscriptions to one guinea each, 



and to receive them only from members of one of 

 these five societies, of all of which the deceased was 

 a member. Subscriptions are payable to Mr. James 

 Forrest, secretary of the Institution of civil engi- 

 neers. 



— Dr. Asa Gray's ' Flora of North America,' part ii. 

 (Caprifoliaceae-Compositae inclusive), is at length 

 issued. It contains 474 pages, mainly devoted to 

 Compositae, which number 1,610 species arranged in 

 237 genera. For the convenience of distant botan- 

 ists, it is sent by mail, free of postage, to those who 

 remit the price ($5), and order it of the curator of 

 Harvard university herbarium, Cambridge, Mass. 



— In September next a geographical professorship 

 will be established at each of the Russian universi- 

 ties. In Germany, fourteen out of twenty-one uni- 

 versities have a chair of this sort. 



— Lessar is again in the Seraks country, and will 

 explore the middle part of the region watered by the 

 Murghab River, which has never been visited by 

 Europeans. 



— The international society for the cure of oph- 

 thalmia offers a gold medal for the best essay on 

 diseases of the eye. The medal is designed by 

 Hartzes of Berlin, and bears a portrait of Albrecht 

 von Graefe. 



— In Russia the statistics of the last thirty years 

 show a great diminution in the forest-trees, but scan- 

 tily replaced by the planting of firs, as there is no 

 supervision of forests : there is said to be a consequent 

 change for the worse in the climate, and diminution of 

 fruitfulness, especially in the districts round Nishni 

 Novgorod and Moscow. In the Moscow government, 

 which used to be rich in fruit-bearing trees, apples 

 and cherries have much decreased in number, and 

 pears have wholly disappeared. 



— A new fog-horn, invented by Mr. Bryceson, has 

 recently been tried on the Thames by the represen- 

 tatives of the admiralty. It is in the form of a pump, 

 and is worked by a strap fastened to the signalman's 

 foot, and so worked as to produce short or long 

 sounds, as required. The advantages of the invention 

 are, the length of time to which the sound can be 

 drawn out, its cheapness, and the fact that it can be 

 heard for three-quarters of a nautical mile in stormy 

 weather. 



— The vertical camera, for use in photographing 

 natural-history objects, is described in a pamphlet, 

 " La photographie appliquee aux sciences biologiques 

 et le physiographie universel," by Dr. A.-L. Donna- 

 dieu, and published at Lyon by J.-B. Carpentier. 



— In the Monthly notices of the Royal astronomical 

 society for May, appears a paper by Professor Hall, 

 upon the motion of Hyperion, the satellite of Saturn 

 just outside of Titan, and whose motion is greatly 

 perturbed by the latter, both on account of its mass, 

 and the nearness and eccentricity of Hyperion's or- 

 bit. The mean motion of Hyperion is still somewhat 

 uncertain, from the fact that there are no systematic 

 observations of it since those of Lassel in 1S52. until 

 Professor Hall took up the systematic observation of 



