264 AMERICAN GRAPE CULTURE. 



is raised three or four feet high. Unless the 

 mass of leaves are put firmly together, it will 

 not only require considerable time for them to 

 heat, but the heat will be low and not uniform ; 

 and they will not heat at all unless they are 

 moist. These two particulars must therefore be 

 attended to carefully. If leaves and manure are 

 used together, they must be well mixed. The 

 operation should be performed quickly, in order 

 that the small amount of heat already in the 

 mass may not be lost. 



Having laid up the bed of leaves, the frame 

 is put on *so as to set level. For raising vege- 

 tables, etc., the frame is placed with its front to 

 the south; but for our purpose we shall place 

 the front to the north. Leaves must then be 

 packed around the outside of the frame up to 

 the top. Next, clean sand must be put in to 

 the depth of about six inches, leveled off neatly, 

 and the sashes put on. All these things must 

 be done as rapidly as possible, in order that 

 there may be no unnecessary loss of heat. 



The sashes must be left on for a few days be- 

 fore the eyes are put in, in order that the sand 

 may become uniformly warmed. In conse- 

 quence of the sashes facing the north, the sun 

 will have comparatively little effect upon the 



