44 THE GRAPE CULTUKIST. 



pipe passes back along by its side, both lying on iron rests, 

 made for the purpose. This arrangement gives eight pipes 

 the whole length of the house, besides the elbows and the 

 few feet that it takes to cross the end. The center frame 

 has four pipes under it, while the side frames have but two. 



The center frame may be used for starting those varie- 

 ties that are the most difficult to strike, or the pipes may 

 only pass under the two outside frames, and the center one 

 be used for the plants when they are first placed in the 

 small pots or the pipes may pass under the center frame 

 and return under the outside ones without returning as 

 shown. 



If the house is twenty or more feet in width, then for 

 convenience the center frame should be double the width 

 of the outside ones, and in that case the four pipes will be 

 needed under it to keep its temperature equal to the. others. 

 Again, in place of frames through the center, a table may 

 take its place, on which to set the plants after they become 

 sufficiently rooted not to need so much heat or so confined 

 an atmosphere as while young. 



The inside frames are only necessary while the cuttings 

 are rooting, and for a few days after the first shift, but 

 they are indispensable when a number of varieties are to 

 be grown, for the air can not be kept sufficiently confined 

 in a large house to insure success with all. To be sure, 

 there are varieties that will grow from single-bud cuttings 

 without recourse to frames, but w r ith such as the Delaware, 

 which seldom shows any roots until the young shoots 

 appear, it becomes a very difficult matter to prevent a too 

 rapid evaporation from the young leaves in the open house. 

 If this takes place, of course the cutting dies, for, until the 

 roots are produced, the young growth is supported entirely 

 upon the alburnous matter contained in the cutting. 



The frames are ventilated by raising one end of the sash, 

 as shown. They should be made one foot deep, and of 

 good, sound plank. The pipes must be entirely shut in so 



