WIDE GREENHOUSE AND ROSE HOUSE. 97 



seen in figure 25 (one-eight of an inch to the foot scale), 

 which shows a slope or angle of fifteen degrees. 



It will be noticed in this design (figure 25) that the 

 larger number of pipes are placed under the front bench, 

 there being four there, while there are only two under the 

 back bench. The slope of the ground makes this arrange- 

 ment necessary in order to secure an equal distribution 

 of heat. It will be observed that there are six "runs" 

 of four-inch pipe for each house; this will give a temper- 

 ature of fifty degrees at night in the coldest weather. If 

 a higher temperature is wanted, an additional " run " of 

 pipe should be added for every five degrees. For fur- 

 ther information see " Modes of Heating," page 98. 

 With the ordinary arrangement of pipes (half under 

 each bench), the back of the house would always be 

 much the warmest, as a moment's reflection will make 

 manifest. The position of the ventilators near the ridge 

 is distinctly marked in this and all the other figures, the 

 dotted lines showing a ventilator raised or open. The 

 position of the benches is also shown. Through the mid- 

 dle there may be either a bench or a solid bed of earth. 

 By use of the scale (one-eighth of an inch to the foot) the 

 proportions of the details of this house may be readily 

 obtained. 



The construction of greenhouses when formed of con- 

 crete, stone, or brick, is not only more costly, but after 

 the wall has risen to the surface of the ground, it is found 

 that, unless the wall of stone or brick is very thick indeed, 

 the high temperature and moisture inside of a greenhouse 

 soon injures the mason work by warring with the low 

 temperature outside, particularly on the north or north- 

 west side. For this reason it has been found that woodeii 

 walls, for ordinary purposes, are equally as good as an 

 eight-inch brick wall for resisting cold, far cheaper, and 

 more durable. 



A common error with the Inexperienced is to build the 



