16 
THE FLOKIST AND POMOLOGIST 
[ January, 
foot of surface covered. Of course, in protecting espaliers, both sides must be 
enclosed. It is proposed here to form a back of canvas, or other textile fabric, 
and to cover the front with glass. At times, however, this arrangement would 
be reversed. By placing the opaque side to the south, the blossoms would be 
retarded, instead of forwarded ; and perhaps, as a rule, this would be the safest 
mode of using the reversible glass walls in the spring. The great danger, at that 
