346 Glass 



have much advantage of protection froitx windbreaks, and, 

 containing a less body of air, they do not give as early 

 results as well-made coldframes. 



For starting plants in a small way, a glass-covered box 

 in the kitchen window may answer very well. An incu- 

 bator is useful for the germinating of seeds. 



4. HOTBEDS 



A hotbed has artificial bottom heat. This heat is 

 ordinarily supplied by means of fermenting manure, but 

 it may be obtained from, other fermenting material, as 

 tanbark or leaves, or from heat in flues and pipes. The 

 hotbed is used for the very early starting of plants, and 

 Avhen the plants have outgrown the bed, or have become 

 too thick, they may be transplanted into cooler hotbeds 

 or into coldframes. Some crops, however, may be carried 

 to full maturity in the hotbed itself, as radishes and let- 

 tuce. The date at which the hotbed may be started with 

 safety depends almost entirely Upon the means at com- 

 mand of heating it and on the skill of the operator. In 

 the Northern States, where outdoor gardening does not 

 begin until the first or the last of May, hotbeds are some- 

 times started as early as January; but they are ordinarily 

 delayed until early in March. In exposed places, it is 

 well to have the glass as near the level of the ground as 

 possible. 



Handling the horse manure. 



The heat for hotbeds is commonly supplied by the 

 fermentation of horse manure. It is important that the 

 manure be uniform in composition and texture, that it 



