408 
SCIENCE OF BOTANY. 
from the under branches which generally very nearly salute the 
ground; hence the tree remains unhurt. Thus “Omega” may learn 
why beech trees are generally preserved from destruction by light¬ 
ning ; and Mr. Frost may be informed that when a powerful accu¬ 
mulation of electricity is conveyed into dry earth, for the want of a 
conducting medium, an explosion will take place, and destruction 
must be the result; hence the reason why conductors attached to 
buildings, should have their terminations conveyed into ivater, or 
very moist ground at some distance from the buildings ; and hence 
the reason why the tree referred to in Mr. Frost’s paper, was torn up 
by the roots, if it stood in a dry situation ; for, if the fluid conveyed 
down the trunk and leaves to the earth, seized upon the roots, (they 
being a better conductor than dry soil) a discharge might take place 
that would be sufficiently powerful to tear the tree from the earth. 
The reason why persons and animals suffer from sheltering under 
trees during a thunder-storm, is owing to their being better conduc¬ 
tors than the dry trunks of trees ; consequently, if their bodies come 
nearly in contact with the under branches, they become a ready me¬ 
dium for conveying the fluid to the earth, but owing to the non-con¬ 
ducting property of the general clothing of either men or animals, it 
is not conveyed with sufficient facility to the earth to prevent des¬ 
truction. 
Sheffield, August ls£, 1833. 
ARTICLE XIII.—ON THE SCIENCE OF BOTANY. 
BY MR. F. F. ASHFORD. 
ON PAPILIONACEOUS OR BUTTERFLY SHAPED FLOWERS. 
If your readers will still join me in the pursuit of so delightful a 
study, I will resume the subject and endeavour to describe six of the 
tribes first, in order to render the general structure of the character¬ 
istic parts of plants familiar. 
Peas being at present in full fructification, you must seize the 
moment to observe their characters, for they are of the most curious 
that botany affords. 
The flowers of this tribe, being of a very particular structure, you 
must not only take several pea-flowers, and dissect them succes¬ 
sively, to observe all their parts one after another, but you must no¬ 
tice the progress of the fructification from the first flowering to the 
maturity ol the fruit. And in the first place, you will find a mono- 
