HEAT OF FERMENTING MANURES. 93 



most available, is yet expensive, — insufficient to meet the 

 exigencies of winter, and is very unsatisfactory in its results. 

 Though the heat of fermenting manure is most genial at , 

 certain stages, yet it is of necessity fluctuating, and may fail 

 at the most critical time ; it involves a great amount of labor 

 and considerable loss of material, and on the whole must be 

 regarded as a most expensive method of heating during the 

 winter months. In permanent frames a single hot-water pipe 

 running along the front would be far more satisfactory. 

 Some crops, like the lily of the valley and Neapolitan violets, 

 might be successfully and economically forced in this way, 

 even in midwinter. 



It is undoubted economy to construct these frames more 

 thoroughly than is usually the case. A south-eastern hillside 

 is the best position. Thorough drainage will contribute 

 essentially to the ease in management, and also to the 

 warmth of the soil. To this end, a gutter to carry off the 

 rains is very desirable. With a dry, warm soil secured, 

 "bottom heat" is not essential, nor is it as desirable for most 

 plants as is supposed. For a frame of any considerable 

 length, a hot-water pipe would give not merely a steady and 

 permanent heat, but also at very much less cost than by the 

 laborious and wasteful method of stable-manure. The space 

 to be heated is so limited, and the cost of heat by coal is so 

 small, that the economy of mats and board covers is more 

 than doubtful. If the frame is made with rest-bars for the 

 sashes, with a separating mid-rib, a single three or four 

 inch pipe will be amply sufficient for the coldest weather. 

 A four-inch pipe, put up, will cost but thirty cents per run- 

 ning foot. Straw matting costs twenty-five cents per running 

 foot. The labor of placing and caring for mats is very great, 

 not to speak of the waste. By the manure method, mats and 

 additional board covers are considered essential for winter 

 work. I am confident this method must give place to others, 

 less wasteful and requiring less labor. The tendency is, and 

 will continue to be, in the direction of permanent houses, 

 which shall be accessible from within, even for the culture of 

 the most hardy and cold-blooded plants. 



I have recently seen an essentially modified form of the 

 frame in use by Mr. Morse, of Newton, in which I am told he 



