487 



in independent determinations, taking fresh quantities each time. 

 For K^ we found: 



25° 

 d-^ 8.641; 8.644; 8.642, mean 8.643. 



4. After heating K^ at a temperature of 150° during 95 hours 



in a current of dry carbon-dioxyde which was freed from oxygen, 



we found : 



25° 

 ^-^8.630 and 8.633. 



These figures show that the density of the metal had not been 

 changed by the heating. 



5. As there was a possibilitj- that we had passed a transition 



point, but that cadmium showed similar retardations to those which 



we had found in the case of bismuth (and tin), we heated a certain 



/ 25° A 



amount of K„ ( d —^ = 8.643 I during 3 days and nights at 100° in 



contact with a dilute solution of cadmiumsulphate. After this time 

 the metal was chilled (at 0°) and washed with water, dilute hydro- 

 chloric acid (these liquids had been cooled) alcohol and aether. It was 

 then dried at 30°. Two determinations of the density gave: 



25" 

 d—^=rz 8.633 (and 8.633) 



This experiment showed, that by heating at 100° a change had 

 been produced in the metal which lowered its density (measured at 

 25°.0) by 10 units in the third decimal place; our duplicate determin- 

 ations prove that this difference exceeds considerably our experimental 

 errors. 



6. In order to determine if a change of density takes place at tem- 



/ 25° \ 



peratures below 100°, we warmed the metal d —- 8.633 and 8.633 



again in contact with a solution of cadmiumsulphate during 14 hours 



at a temperature of 60° — 70°. After the manipulation the metal was 



chilled, washed, and dried in themanner described above. Its density 



was now : 



25° 

 d — 8.620, 

 40 



which proves that there occurs at 60 — 70° a diminution of the 

 density of 11 units in the third decimal place. 



7. We repeated the experiment described in § 6 with the specimen 



,25" 

 the density of which was now d — 8.620, keeping it this time 



