192 PHOSPHORESCENCE. 
It is well known that when a platinum wire is 
suspended, after being heated, in a mixture of 
ether-vapour and air, or in a mixture of alcholic 
vapour and air, it continues incandescent for 
hours together, until all the ether or alcohol em- 
ployed is spent. In this case, the spirituous 
vapour is burnt by the oxygen of the air; but 
neither the oxygen nor the ether become lumi- 
nous,—it is the wire alone which gives out light. 
This curious phenomenon may go far, perhaps, 
to explain the phosphorescence of dead animal 
matter. The whole circumstances connected with 
it have been brought forward in my prize memoir, 
‘La Force Catalytique, ou Etude sur les Phéno- 
ménes de Contact,’ printed at Harlem in 1858 
(see Appendix). 
As regards phosphorescence in the vegetable 
kingdom, possessing, as we do, only a few isolated 
observations, we are devoid of sufficient experi- 
mental data to offer any theoretical consideration 
as to its production. If the hght emitted by 
flowers appears to be electrical, that evolved from 
fungi is more probably connected with chemical 
action. 
In lummous animals, we find everything pre- 
pared by nature for the production of light; 
namely, a phosphorescent organ specially adapted 
for this purpose. 
Taken in its most satisfactory point of view, the 
