Diamond, 
Graphite, 
Charcoal, 
245 
Mean Sp. Gr. 
3-48 or 3-461. 
2-29 
1-88 
5. We have now to consider whether these numbers stand in 
any simple relation to their atomic weight. The formula 
gives the following atomic volumes, taking £=12. 
Diamond, 
Graphite, 
Charcoal, 
Atomic Volumes. 
3-44. 
5- 24. 
6- 38. 
These numbers do not bear to each other any simple relation. 
6. If we now take the atomic weight of carbon (£= 12), and 
then extract from it its square, cube, and fourth roots, numbers 
are obtained which bear a striking approximation to the mean specific 
gravity of the three forms of carbon: — 
Roots. 
L - V~W- 3-464 
2 - \/ 12”= 2-289 
3 - a/ 12 = 1-865 
Sp. Gr. 
Diamond, 3-48 or 3*46. 
Graphite, 2*29. 
Charcoal, 1‘88. 
In other words, if we raise the specific gravity of diamond to its 
second power, that of graphite to its third power, and that of char- 
coal to its fourth power, we obtain numbers closely approaching in 
each case to 12, the atomic weight of carbon. 
Diamond, 
Graphite, 
Charcoal, 
3*48 2 = 12'11. 
2-29 3 = 12'00. 
D88 4 ^12-49. 
These approximations are remarkable, and the relations of the 
numbers are natural and simple. The differences between the 
mean experimental numbers and the corresponding roots of the 
atomic weight of carbon are not so great as the differences observed 
in the specific gravities of the same form of carbon. 
