56 



was filled up with paraffin oil and a (piantitj- of small glass-beads. 

 (Vide our first paper § 10). At no teinjierature between 50 and 100° 

 (vide § 4 of our first paper) did any change occur. We then added 

 100 grams of the same material K^ which had been in contact with 

 a solution of cadmium sulphate (at 50°) during 12 hours. We now 

 observed that the meniscus of the dilatometer 



fell 167 mm. in 5^ hours at 50°.0 



„ 213 „ „ 7i „ „ 70°.0. 

 This result is in perfect accordance with the observations of § 3. 



5. The following experiments prove in a more quantitative way 

 that the previous thermal history of the metal has an influence on 

 the transition temperature. 



A fresh quantity of the metal (/fj was divided into two parts 

 [(/TJ/ and {K,)ii] of 500 grams each. 



{K^)i was reduced into turnings on a lathe and immediately put 

 into a dilatometer. At 69°. 9 we observed a decrease of volume 

 1^456 mm.) in 257* hours. 



• iK^)j2 was converted into turnings in the same way and kept 

 for 5 days and nights at 100^ in a solution of cadmium sulphate. 



After having it put into a dilatometer (bore of capillary tube 1 mm.) 

 we made the following readings (Table I). 



TABLE I. 



Temperature. 



Duration of ttie 



observations in 



hours. 



Increase of the 

 level in mm. 



Increase of the 



level 

 in mm. per hour 



49.6 

 60.4 

 62.5 

 63.1 

 63.7 

 69.6 



— 100 



— 125 



— 14 



+ 15 

 + 83 

 + 225 



— 600 



— 250 



— 21 

 + 45 

 + 249 

 4- 2700 



The transition point is 6 2°. 8. 



6. The metal was now kept at 100^ in contact with a solution 

 of cadmium sulphate for 7 days and nights. After this it was put 



