TABLE 2O4. 



CONDUCTIVITY FOR HEAT. 



Metals and Alloys. 



The coefficient k is the quantity of heat in therms which is transmitted per second through a plate one centimetre 

 thick per square centimetre of its surface when the difference of temperature between the two faces of the plate 

 is one degree Centigrade. The coefficient k is found to vary with the absolute temperature of the plate, and is ex- 

 pressed approximately by the equation kt=^k (i -f- at). In the table k is the value of kt for o C., t the tempera- 

 ture Centigrade, and a a constant. 



* A repetition of Forties's experiments by Mitchell, under the direction of Tail, shows the conductivity to increase 

 with rise of temperature. (Trans. R. S. E. vol. 33, 1887.) 



t Herschel, Lebour, and Dunn (British Association Committee). 

 SMITHSONIAN TABLES. 



197 



