On the Spheroidal State. 91 
The paraffin was melted by immersing the flask in boiling water. 
After half an hour the flask was allowed to cool in vacuo and 
weighed. This operation was now repeated, the paraffin being 
heated for an hour by enclosing the entire flask and part of the 
tube communicating with the pump in a metallic vessel which 
was immersed in boiling water. The paraffin having been 
allowed to cool wm vacuo was found on again weighing the flask 
to be precisely the same weight as it was originally. I could 
have detected a loss of 0:00005 gramme or 54555 of the weight 
of the paraffin if it had taken place, and considering that the 
temperature employed was 10-20° higher than that at which 
spheroids of paraffin are readily produced, I think one may reason- 
ably conclude that paraffin is not appreciably volatilized at a 
temperature which admits of the existence of a spheroid on its 
surface. And since the spheroid must in this case be at a lower 
temperature than the liquid on which it floats, it is even less 
likely to produce vapour sufticient to keep it floating. In confir- 
mation of this conclusion I may mention that I have been unable 
to detect the slightest diminution in the size of paraffin spheroids, 
though I was occasionally much puzzled by the appearance of 
small spheroids in the place of large ones which I had left 
floating a short time before, until I detected one of these large 
drops disappearing with a slight splash which called into existence 
a new spheroidmuch smaller than its predecessor. These experi- 
ments in all their details are in accordance with Mr. Stoney’s 
explanation of the phenomenon, and they demonstrate that the 
previously accepted theory is untenable. 
It is noteworthy that in 1874 Mr. Crookes* suggested that “ The 
phenomenon of the spheroidal state is probably due in some 
measure to a repulsive force exerted between closely approxi- 
mated bodies, one of which is at a very high temperature.’ And 
although the true nature of“ the repulsive action of radiation,” to 
which Mr. Crookes considered the phenomenon attributable was at 
this time unknown, he ventured to anticipate “that a condition 
similar to the spheroidal state will be found to obtain between 
non-volatile bodies.” 
* Philosophical Transactions of the Royal Society ef London, vol. clxiv., part 2. 
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