Polytechnic Association Proceedings. 603 



With no substance SO'* 



With teUurium 80* 



With zinc 80° 



With manganese 80^ 



With cast iron 80" 



With graphite 79° 5' 



With coke 79° 20' to 80° 



With manganese 19° 20' 



With sulphuret of antimony 0° 



Withsulphur 0° 



"With the cups arranged as simple, or quantity battery — i. e., 

 the positive poles connected, and the negative poles connected — 

 the deflections were: 



Quantity gal v. 



Intensity galv. 



With no substance. .. 



With tellurium 



With zinc 



With magnesium 



With cast iron 



With graphite 



With coke 



With manganese 



With sulphuret of antimony 

 With sulphur 



28' 

 26' 

 27' 

 27' 

 21" 

 15' 

 20' 















20' 

 50' 

 40' 



10' 

 to 27 



62° 

 62° 

 62° 

 62° 

 62° 

 61° 

 61° 10' to 62° 















This shows how little capable a quantity current is of overcoming 

 resistance; for even the manganese, which, under the intensity 

 current, admitted a deflection of nineteen degrees and twenty min- 

 utes, under this, seemed like a perfect insulator, even by the very 

 sensitive quantity galvanometer. 



Tellurium heats readily, though not quite so rapidly as zinc, and 

 it cools a little more slowly. 



It is not to be expected that, with pieces so small, and with so 

 weak a battery, very nice and exact results are to be attained; but 

 the foregoing are suflicient to show that tellurium is a good con- 

 ductor of both heat and electricity; and we see that it possesses a 

 brilliant metallic luster. 



The question arises, therefore, why is it that chemists, especially 

 those of France, have recently ranked it among the non-metallic 

 substances? 



Metallic luster and conducting power have always been looked 

 to as the distinguishing characteristics of metals. Kane says: "By 



