630 



the pyciioineter was continually falling at constant temperature. The 

 same phenomenon was observed when the experiment was repeated. 

 This indicates that the metal undergoes some change at this temperature. 



3. By manipulating very quickly we succeeded in determining the 

 density at 25 .0 We found in two independent experiments : 



25°.0 



d 8.889 and 8.890. 



4° 



Our thermometers had been compared with a standard of the 

 Phys. Techn. Reichsanstalt at Charlottenburg-Berliu. 



After having healed the metal during 24 hours at 100° in a 

 solution of coppersulpliate no change of density was observed. Re- 

 peating this experiment at 2ö°, we found 



25°.0 



d 8.899 and 8 900 



4° 



These experiments prove that there is a transition temperature 

 between 25° and 100° C. 



4. In order to tix this temperature more closely we carried out 

 a determination with the dilatometer. using 300 grams of our chilled 

 metal. The dilatometer (bore of the capillai-y tube 1 mm.) was filled 

 with paralKinoil, which had been heated for some hours in contact 

 with finelv divided copper, until there was no more evolution of 

 gasbubbles. 



The dilatometer was now kept at different, but constant temperatures. 



