SILKWORM GRAIN. 329 
The height of the mulberry tree, from the ground to 
the top, should not exceed two feet six inches. I have 
proved, by experience, that this size is most convenient 
for covering with, and removing the manchon. 
The whole apparatus consists of a few feet of wire 
gauze and canvas, some cotton, and string. In order 
to enable the reader to comprehend accurately this 
procedure, of elementary simplicity, I will indicate the 
exact dimensions of the manchons which I make use 
of. I take some wire gauze of eight threads to the 
centimetre (i.e. twenty threads to an inch), on which a 
coat of oil paint is lain, to preserve it from rust. The 
breadth must be three feet six inches. If the gauze 
cannot be had of this size, two breadths may be 
fastened together with wire, or tarred silk. The length 
must be eight feet ten inches, and the two ends 
brought together will form the circumference of the 
manchon, with an interior diameter of 35 inches, 
sufficient for an ordinary sized tree. 
All round the circumference of the top and bottom 
of this wire gauze tube I sew on some fine canvas, 
previously steeped in oil, and this must be two feet 
broad. As a matter of course the paint must be 
thoroughly dry before the manchon is used, and all 
green colour must be avoided, on account of its 
arsenical exhalations. 
When the manchon has been made open at the top 
and bottom, it is slipped over the tree, so that the 
lower canvas may be tied round the stem of the tree, 
just below the branches, taking care to wrap some 
wadding round it, lest the string should injure the 
bark ; and, in like manner, to put some at the point 
of junction of the bark and canvas ; for the purpose 
