February 13, 1902] 



NA TURE 



549 



A VEAR ago. the Scienlia Club of Paris gave a dinner in 

 honour of Prof. E. J. Marey, the eminent French physiologist, 

 whose work has disentangled the intricacies of many animal 

 motions. At the close of the banquet, Prof. Marey's numerous 

 colleagues, friends and pupils expressed the desire to give tan- 

 gible testimony of their admiration of his scientific achievements. 



r 



t IG. I. — M. iMarey in his laboratory. Reverse ol ined.'\l. 



and eventually it was decided to present him with a com- 

 memorative medal. This souvenir was engraved by Dr. Paul 

 Richer, and the accompanying illustrations from La iValtiie 

 show its remarkably fine character. The presentation was 

 made to Prof. Marey at a meeting held at the College de France 

 on January 19. M. Leygues, Minister of Public Instruction and 

 Fine Arts, occupied the chair, and a large number 

 of eminent men of science and other representatives 

 of learning were present. M. Gaston Paris, ad- 

 ministrator of the College, gave expression to the 

 feelings of those who had combined to show their 

 admiration of Prof. Marey's contributions to the 

 study of physiological actions ; and he was followed 

 by M. Franck, one of Prof Marey's old pupils, who 

 described the work of his master. M. Chaveau 

 spoke as an old and close friend, and M. Leygues, 

 after referring to the chief characteristics of Prof 

 Marey's researches, remarked in conclusion: — " le 

 prie Monsieur Marey, au nom du gouvernement 'If 1 1 

 Republiijue, dont je suis ici le representant, d'a^r^ - 1 

 I'hommage de sa reconnaissance et de sa respeciu l 

 admiration." Letters and telegrams of congratula- 

 tion were received from many physiologists unable to 

 be present at the meeting ; and Prof. Marey replied 

 in appropriate terms of thanks to the numerous 

 expressions of regard of which the medal which 

 has been presented to him is a token. 



Referring to the experiment described by Mr. 

 F. Hodson in last week's Nature (p. 319), Mr. aBUiM 

 J. D. T. Morris writes from the East London 

 Technical College to say that it is possible to produce 

 both kindsof electrification in sealing. wax by rubbing 

 it with silk. As with the glass rubbed with fur, gentle rubbing 

 produces positive electrification and more vigorous rubbing pro- 

 duces negative electrification. The change is probably due to 

 NO. 1685, VOL. 65] 



difference of temperature of the surface of the material used, 

 caused by the varying amount of energy used in the friction. 



A NEW monthly journal has just been started at Florence, 

 bearing the title La niiova Rassegna iecnica internaziouale. It 

 contains abstracts 0/ important papers on engineering and ap- 

 plied science, a summary of current literature in this 

 region, both Italian and foreign, notices of books, of 

 exhibitions, prizes, vacant appointments and con- 

 gresses. In the present number, projected railways 

 and automobiles receive a fair share of attention. The 

 Kassegna should be useful in giving a synopsis of 

 the most important topics of the day in connection 

 with practical engineering. 



Some interesting details relative to trials with 

 secondary batteries for electric traction on branch 

 lines of railway in Germany are given in the issue of 

 the Ceiilralblatt fiir Accitmulaloren- iind Elexienlen- 

 kttnde for December 15, 1901. These trials were 

 instituted in 189S, after a special form of PJante 

 cell had been devised for the particular work. The 

 negative plates of the cells were -found in actual use 

 to have a shorter life than the positive plates, and it 

 was necessary to take these out and to repaste them 

 after they had^done duty for 30,000-40,000 km. The 

 Intteries were carried under the seats of the car- 

 riages, and weighed fifteen tons : while the complete 

 weight of a carriage, with its motor equipment and 

 complement of 112 passengers, was fifty-three tons. 

 Two of these larger carriages and two smaller ones, 

 with accommodation for sixly-eight passengers, were 

 built, and were regularly run on branch lines con- 

 necting the following towns in the Palatinate: — Ludwigshafen 

 Neustadt, Worms, Schifferstadt, Landau and Amweiler. The 

 normal speed at which these carriages were run was one of 45 

 km. per hour. The total cost of the larger carriages was 2750/., 

 the electrical equipment representing 1625/. of this total. The 

 running costs are stated to have been 27'5 pfg. per car kilo- 



iX LI 1 ■ 



:AKIElL^ 



-M. Marey, Member o( Ihe Instiluteof Fr: 



metre when generating charges were included, and only 2t pfg. 

 when the batteries were charged at the central lighting station — 

 presumably in Ludwigshafen. The corresponding charge for 



