NAT. ORDER.— AMADYLACEjE. 
117 
in counteracting the frost, seems to produce its effect in a manner 
analogous to the application of cold water to a frozen joint or limb, 
which is injured by the sudden application of warmth." An ac- 
quaintance of mine informs me that he protects his blossoms by re- 
tardation ; and the means used are, detaching the branches of the 
trees from the walls in autumn, and not refixing them till late in the 
spring, when the blossoms are about to expand. In addition to un- 
fastening the trees, a wedge is put in behind the main stem to throw 
it forward, in order that the trees may receive as little protection 
from the wall as possible. 
Ripening Peaches on leaflet branches. Wherever the part of the 
bearing branch which extends beyond the fruit is without foliage, the 
fruit itself rarely acquires maturity, and never its proper flavor and 
excellence. This is supposed to be owing to the want of the re- 
turning sap, which would have been furnished by the leaves ; this 
seems to have been proved experimentally by inarching a small 
branch immediately above the fruit. The fruit in consequence ac- 
quired the highest degree of maturity and perfection. 
Insects and diseases. The leaves of the Peach-tree are liable to 
the attacks of the acarus, its greatest enemy ; and also to be devoured 
by the chermes, aphis, and even a much smaller insect, the thrips. 
These are to be kept under by the usual means of watering over 
the leaves, and fumigation with tobacco smoke. The honey-dew, 
mildew, gum, and canker, are chiefly to be kept under by regimen ; 
dusting with sulphur has been found to destroy the mildew, but the 
only certain way of remedying it is by a renewal of the soil, which 
will commonly be found old mould, long in use, and too rich, and by 
abundance of air. We are informed that I. Kirk tried renewing the 
soil for fifty years, and always found it an effectual remedy. 
The young wood of the Peach-tree is liable to be covered with 
black spots or blotches, which Kenment proved to be produced by 
over rich soil. The fruit, when ripe, is liable to the attacks of the 
wasp, the large fly, and especially the earwig, &c. ; the first two 
