NOTES ON WINTER GARDENING. 87 



general, however, for commercial purposes a cheap forcing 

 house is to be preferred to the "fire hot bed," as such a house 

 may be put up at but little greater expense and the cost of 

 maintaining is but little more, whereas the work may be done 

 much more easily and satisfactorily than is possible with the 

 hot bed. In short, a forcing house may be described as a hot 

 bed large enough to get inside of. 



3. The Forcing House. 



a. The Lcem-to: — The lean-to or shed- roof house is a natural 

 development of the cold frame or hot bed, and temporary 

 houses may very easily be made by placing ordinary hot bed 

 sash by the side of a wall. This form has the advantage of 

 cheapness in that the sides of a building may be utilized, but 

 it has the disadvantage of allowing light to come in from only 

 one side. A lean-to house should naturally be placed upon the 

 south side of the wall or building. 



b. The Uneven-Span House: — The form in most common use 

 at the present time is the so called two-thirds or three-fourths 

 span house. It is similar to a lean-to excepting that the peak 

 has been cut off, thus doing away with a large amount of waste 

 space and allowing more light to come in. In general, houses 

 of this description are placed east and west with the long slope 

 to the south. Recently there has been some discussion con- 

 cerning the merits of the practice of placing the short slope to 

 the south. The advantages claimed for this practice being that 

 the rays of the sun are much more directly received by the 

 sharper angle; that the snow slides off more quickly; and a 

 third doubtful advantage claimed is that on the north side the 

 long slope will retain the snow to a certain extent and thus shut 

 out cold drafts. The uneven span house is the form almost 

 universally used for the growing of roses and for most com- 

 mercial purposes. Figure i represents such a house at the 

 Experiment Station, which is used for growing lettuce. 



