F. W. Clarke on the Atomic Volumes of the Elements, 309 
parable circumstances this apparent multiple relation would 
prove to be exact ? 
The oxygen group, oxygen, sulphur, selenium, and telluri- 
um, affords a still more remarkable series of values. The 
atomic volume of oxygen in its solid compounds, varies accor- 
ding to the nature of the combination. For this element in 
the solid state Kopp has deduced three values,—2‘6, 5:2, and 
‘4. Kopp himself has called attention to the fact that these 
stand to each other as 1:2:4.* For this element in liquid 
h 
_ of sulphur varies, both with its crystalline form, and with the 
seem to vary from this rule. Their atomic vol- 
iti i na’s 
‘<4 
0°7, as the atomic vol- 
but 0:3 from twice the 
* Buff, Kopp and Zamminer. “Lehrbuch der Physicalischen und Theoreti- 
Schen Chemie.” 
