( 441 ) 



Physics. — "J (li'li'riiniHihon of the I'lcclroclicni'Kui I <'(jii/r/i/i'/if i)f 

 .■^ilrcr'" l>v (i. VAN Di.iK and .1. I\i nst. (romniuiiicated by 

 I'roC II. I1a(^a.) 



The [triiici|»al (Iclcnniiialioiis of tlic cicclroclK'inical (M|iihaleii[ t)t' 

 sil\ei' lia\e yielded the follow iiiii' xaliies:^) 



xMascart 0,01115(5 i884 



F. and W. K()iii,RArs(n 0,01 lis:} 1884 



Lord Ravi. KKni and Mrs. SiiHJWicK 0,01 I17i) 1884 



Pkllat and PoTiKR 0,01 1 ll)-2 1890 



Kahlf, 0,011183 1898 



P.\TTF,RS().\ and (Utiif, 0,011192 1898 



Pkllat and Lkdic 0,011195 1903 



The difference in these iinnihers is dne, partly to the method of 

 the detei'niination of the strength of the enrreiit, pai'tly to the way 

 of ('onstrncting and u^ing tlie voltameter. 



Ill most of the imestigations the streng! h of the cnrrent was 

 measvired hy means of an electrodynamometer in some foi-m or other, 

 either directly or indirectly with the aid of a standard cell (cell of 

 CYark). V. and W. Koiii.raisch nsed a tangent galxanometer. 



For the voltameter the circumstances dilfered as to the composi- 

 tion and the concenti-ation of the electrolyte, the shape, the dimensions 

 and the com|»()sition of the cathode, the way of washing and drying 

 the siher deposit. 



I'he "Ijedinunnuen nnter deneji bei der Darstellung des Ampi-irk 

 die Al)scheidnng des Silliers stail/ulinden hat" are inserted in the 

 "Ueichsgeselzblatt" of Mav (>, 1901, i». 127'! amonu' the regulations 

 of the law concerning the electric iiints snl) § hn. 



In connection with the I'ather considei-able dillei-ence between the 

 \alues found for the (.'lectrochemical e(pn\aleut of sil\-ei-, a new 

 investigation as to the value of this <pianlily in which the abo\e 

 mentioned conditions are folloNved, did nol seem l(t b(» su|)erlluous 

 to us. The tangent gahanomeler lia^ been chosen for the measni'e- 

 ment of the strength of the current. ( )w ing 1(» tiie high degree of 

 accuracy with which the constant of this instrument, and the hori- 



1) Mascaut. .loLiiii. <l<.' lMiy>, ["i) o, p. :2s:j. issi F. and W. Kujii.rwvrscii. W'iud. 

 Ann. -11, p. 1, tSSC). \jo\i\ IiAYLKKiH andMis. Siogwick. Pliil. 'I'raiis. 2, p. 411, bSSl. 

 I'ki.lat and Potier. Journ. de Pliys. (2) 9, p. 381, 1890. Kahi.e. Wied. Ann. G7. 

 p. 1, 1S99. Pattkrso.n and (Jutiie. The Phys. P»evicw 7, p. 251, 1898. Pellat and 

 Leduc. Compl. Rend. VM\, p. 1019, i'.»();j. 



'^) Also Zeitschr. i'. lustrunientenk. ü Heft. 19Ul, p. 180. 



