304 



Mr. Carl Barus on the Fusion 



results of the latter (Series II.) are graphically shown in the 

 chart (fig. 4), in which thermal capacity in gramme-calories 

 is constructed as a function of temperature *. Straight lines 

 are drawn through the points, showing the mean specific 

 heats for the intervals of observations, solid and liquid. The 

 letter a marks the region of fusion. 



Table III. — Thermal Capacity of Diabase. Series I. 

 Digest, cf. § 15. 



Mean specific heat, solid, 800° to 1100° . -304. 

 „ liquid, 1200° to 1400° . '350. 

 Latent heat of fusion, at 1200°, 24 g.-cal. ; at 1100°, 16 g.-cal. 



Solid. 



Liquid. 



1 



Temp. 



Thermal 

 capacity. 



Temp. 



Thermal 

 capacity. 



m Thermal 

 Tem PJ capacity. 



Temp. 



Thermal 

 capacity. 



829 



880 



1001 



191 

 204 



242 



1 



1025 

 1078 



tll66 



1 



253 

 263 

 311 







1274 



1306 



i 1337 



358 

 364 

 373 



1367 

 1378 



370 



385 



i 



Table IV. — Thermal Capacity of Diabase. Series II. 

 Digest, cf. § 15. 



Mean specific heat, solid, 800° to 1100° . -290. 

 „ liquid, 1100° to 1400° . -360. 

 Latent heat of fusion, at 1200°, 24 g.-cal; at 1100°, 16 g.-cal. 



Solid. 





Liquid. 



Temp. 



Thermal 

 capacity. 



Temp. 



Thermal 

 capacity. 



Temp. 



Thermal 



capacity. 



Temp. 



Thermal 

 capacity. 



o 



781 

 873 

 948 

 993 



180 

 202 

 227 

 238 



1096 

 tll71 



268 

 302 



1166 

 1194 



1197 

 1215 

 1218 



310 

 318 

 319 

 327 

 330 



1248 

 1251 

 1251 

 1334 

 1352 



339 

 340 

 342 



377 



367 



* The corresponding chart for Table III. is almost identical with this, 

 t Incipient fusion (?) at the base of the crucible. 



