366 Mr. G. F. Emery. [Apr. 



All these were very satisfactory measurements. The zinc sulph 

 solution was not the same as that used before, and the value of 

 the aqueous solution is considerably lower than any of those pro 

 viously obtained. The great alteration in the value of 3 sometime 

 caused by comparatively slight changes in the quality of the solutioi 

 makes it rather difficult to get the same results with two solution, 

 which are apparently alike, and I do not think that this last ralu 

 8*15 need cause doubt as to the substantial accuracy of the previoui 

 results, since two at least of the previous set giving higher values fa 

 5 appeared to be free from any objection. 



It will be noticed that all the additions to this zinc sulphate solutio 

 caused a decrease in the value of 3, that for sugar, as might be ei 

 pected from such an inactive substance, being least and nearly 

 portional to its amount. The presence of the sodic sulphate 

 considerable effect on the value of the change caused by 10 per 

 alcohol, reducing the decrease in 3 by about half its amount, 

 strength of the sodic sulphate added was too great to make 

 results veiy interesting, but I have no doubt that the curve wo 1 

 have come round to the zero at 8'15, like all the others. 



Various strengths of cadmium bromide in alcohol, which was af 

 wards found not to be pure, were tried. The salt appeared to 

 pretty strongly positive, the values observed for 3 being 



For 0*4 per cent, solution = 5'87 

 I'O $ = 7 



4-0 3 = 8-115 



1 gram cadmium bromide in 100 c.c. of normal propyl alcohol 

 = 7-43. 



A few experiments of what are believed to be an entirely nc 

 kind were made on the thermoelectric force generated in a pui 

 liquid circuit, that is, in a circuit composed of two kinds of liquid, 

 junctions being at different temperatures. To measure this E.M. 

 one of the liquids was divided, and between the extremities, wl 

 were kept at exactly the same temperature, two similar elect 

 were inserted. For this the following apparatus (fig. 5) was used. 



The method of observation was as follows : 



The beakers A, A' contain No. 1 liquid, as does the tube C. Of ti 

 tubes D, of which the ends are closed by porous plates, D 1 contaii 

 No. 1 liquid, and D 2 contains No. 2 liquid. The tube D 1 

 placed in position, and when the temperature was steady the E.M.1 

 between F, F', which were at the same temperature connected by 01 

 fluid was measured. Then the tube D 1 was removed, tube D 

 inserted, and the E.M.F. taken as soon as the temperature w 

 steadv. 



