Wiedemann and Franz on the Condudibity of Metals for Heat. 35 



I. Experiments with the cylindrical vessel full of Air. 

 1, Silver, 5 millims. thick. 



3. Gold, 5 millims. thick, 4. Brass, 5 millims. thick. 



5. Iron, 6. Steel, 7. Platinum, 



5 millims. thick. 5 millims. thick. 4-75 millims. thick. 



D2 



