454 



Prof. D. Mendeleeff. Experimental 



FIG. 6. 



at much lower temperatures than they do at ordinary atmospheric 

 pressure. Pellat* pointed out that the proximity of the surface 

 of a metal to that of another metal in air, changes its electrical con- 

 dition, and he attributed this to vaporization of metals, showing 

 that even iron exerted an influence at a distance. Colsonf showed 

 that a photographic plate was affected by the vapour of certain 

 metals, notably by zinc, cadmium, and magnesium even through 

 porous septa. Dr. RussellJ in some recent and very interesting 

 experiments, was led to the conclusion that even so 

 infusible a metal as cobalt will by vaporization, affect 

 a photographic plate. In January, 1897, before hearing 

 of Dr. Russell's experiments, I began some experi- 

 ments with a view to ascertain whether metals, vapor- 

 ized in vacuo near the ordinary temperature, will 

 actually unite to form alloys. The arrangement is 

 shown in fig. 6. A and B are two discs of metal 

 with polished surfaces separated by a ring of glass, the 

 whole being enclosed in a vacuous tube which could be 

 heated in a water bath. I found that when cadmium 

 and silver were opposed for eight days at a tempera- 

 ture of 50 an appreciable deposit of a tinted cadmium- 

 silver alloy formed on the surface of the silver. 

 Cadmium must, therefore, have passed across the 

 interval between the discs A and B. 



The results given in the present paper, reveal addi- 

 tional points of similarity between the behaviour of 

 alloys and that of ordinary saline solutions. I trust, therefore, that 

 it may be useful as a continuation of ray investigation on the 

 " Diffusion of Metals," which formed the subject of the Bakerian 

 Lecture of 1896. 



" Experimental Investigations on the Oscillations of Balances." 

 By D. MENDELEEFF, For. Mem. U.S. Received June 9, 

 Read June 9, 1898. 



In the year 1893 the Central Chamber of Weights and Measures 

 (Glavnaya Palata Mer y Vesov) was created in St. Petersburg to act 

 as a Central Institution of the Empire for the verification of all 

 kinds of standard measures. Having been appointed Director of 

 the above-mentioned Institution, I was first of all occupied in 



* 'Comptes Eendus,' 1882, vcl. 94-, p. 124.7; 1896, vol. 123, p. 104; and 1898, 

 vol. 126, p. 1338. 



t Ibid., 1896, vol. 123, p. 49. 



J 'Roy. Soc. Proc.,' 1897, vol. 61, p. 424, and ibid., vol. 63, p. 102, Bakerian 

 Lecture, 1898. 



