56 Mr . Davy’s Lecture , See. 
except in the case of its evident and powerful concentration 
in the atmosphere. 
Its slow and silent operations in every part of the surface 
will probably be found more immediately and importantly 
connected with the order and oeconomy of nature ; and in- 
vestigations on this subject can hardly fail to enlighten our 
philosophical systems of the earth ; and may possibly place 
new powers within our reach. 
EXPLANATION OF THE FIGURES. 
Plate I. 
Fig. 1, Represents the agate cups, mentioned page 4. 
Fig. 2, Represents the gold cones, page 6. 
Fig. 3, Represents the glass tubes, and their attached appa- 
ratus, page 21. 
Fig. 4, Represents the two glass tubes, with the interme- 
diate vessel, page 22. 
In all the figures A B denote the wires, rendered one posi- 
tively, the other negatively electrical ; and C the connecting 
pieces of moistened amianthus. 
