1880.] On the Essential Properties, &fc, of Beryllium. 



43 



determinations;* the values are referred to pure beryllium, making 

 allowance for the impurities of beryllia and iron : — 



Temperature. 



Specific heat. 



Atomic heat. 





0— 46-30 C. 



0-3959 









0— 46-30 

 0— 46-30 



0-3950 

 0-3980 





5-46 



/Heating in the vapour 

 \ of CS 2 . 



0— 46-50 



0-4005 









0—10018 

 0— 99-97 



0-4250 

 0-4242 





5'79 



/Heating in the vapour 

 \ of water. 



0—214-0 

 * 0—214-0 



0-4749 

 0-4751 





6-48 



/ Heating in the vapour 

 I of nitrobenzol. 



0—299-5 

 0—299-5 



0-5054 

 0-5066 





690 



/ Heating in the vapour 

 I of diphenylamine. 



Thus the specific and atomic heat of beryllium increase with the 

 temperature, but a comparison with the same numbers for iron 

 between — 300° C. shows that such an increase of these values is not 

 unusual. 





0—100°. 



0—300°. 



Authority. 



Specific 

 heat. 



Atomic 

 heat. 



Specific 

 heat. 



Atomic 

 heat. 





0T124 

 0-4246 



629 

 5-79 



0-1266 

 0-5060 



7-09 

 6-90 



Bede. 



Nilson and Pettersson. 



Beryllium. . . 



Between — 100° C, the atomic heat of beryllium is equal to that of 

 aluminiuni=5'87, and gallium=5-59, at 214° C. it is normals 6*48, 

 and at 300° C. it has attained the same value as iron at the same 

 temperature. Beryllium can thus certainly not be compared with 

 the diamond in this respect, the specific heat of which, according to 

 the researches of Weber, being many times higher at — 300° C. 

 than at 0—100° C.f 



Every doubt as to the real atomic weight of beryllium must be 



* We have also been obliged to determine the increase of the specific heat of be- 

 ryllia and platinum by higher temperatures in the same way as that of beryllium 

 itself, the metal for the experiments being enclosed in little capsules of platinum 

 foil, hermetically soldered with chemically pure gold. Glass tubes cannot be em- 

 ployed at higher temperatures than 100° for two reasons : 1st, the glass would crack 

 when suddenly cooled to 0° ; and 2nd, its specific heat increases very rapidly. 



t " Ber. d. Deutsch. Ohem. Gresellsch.," v, 303. 



