244 Intelligence and Miscellaneous Articles. 
established between the thermal and electrical conductibility. Wiede- 
mann has accordingly determined the conductibility for heat and 
electricity of several alloys. He used the same method as in the 
previous researches, and the following Table contains the results at 
which he has arrived. The standard adopted is silver, the conduc- 
tibility of which, both for heat and electricity, is taken at 100. 
Copper-zine - denotes an alloy containing § parts of copper-to tof 
zinc. 
Conductibility for 
(Se ee) 
Heat. Electricity. 
CODPer}) jatstahe ns ste woarne weet 73°6 79°3 
Copper-Zine Fo... sees. 27°3 25°5 
Copper-Zine >... 29°9 30°9 
Copper-Zinc “ aie yd slaps ide 31-1 29°2 
Brass ce Se eraithe cashes 25'8 25°4 
AV i ER AE re het 5 28°1 27°3 
Pin ies oda pvt oldie tals eS 15:2 17:0 
Tin-Biemuth oo, ele 10:1 9:0 
Tin-Bismuth 5 ........+. 5°6 44 
Tin-Bismuth 5 .... 2.05. 2°3 2-0 
Rose’s Metal .........-. -. 4:0 3°2 
From these results Wiedemann concludes— 
1. That the agreement, which had been previously found to exist, 
between the thermal and electrical conductibility of metals obtains 
also for alloys. 
2. That the conductibilities of alloys of zinc and copper, for 
heat as well as for electricity, differ but little, even with a consider- 
able excess of copper, from the conductibility of the worse conducting 
metal, zinc. The alloys of zinc and bismuth, on the contrary, have 
nearly the mean conductibility calculated from their atomic com- 
position.—-Poggendorff’s Annalen, Noy. 1859. 
