86 A CJiaptcr on Greenhouses. 



three-fourths of an inch high ; the shelf to be covered with clean white sand 

 to receive the pots. The paths should be three feet wide. The centre of 

 the house would require tw'o courses in height : the lower one about twen- 

 ty-four inches wide ; the second one to rise about twelve inches, and to 

 cover the remaining space. The shelves should have bands on the edges, 

 and be covered with sand similar to the front ones. 



Ventilation of centre house is provided by the sashes opening on the 

 four sides of the upper part, or cupola, and also at the bottom sides. 



The wings to have flat ventilators in roof, and the sides to open. All 

 the ventilators to be operated with arms fixed upon shafts, so that all in 

 each line may be operated at will ; and to have ball attachment, to keep 

 them tightly closed when shut. The roof of the house should be frosted 

 with a thin solution that will not obstruct the light, and yet kill that burn- 

 ing sensation that comes from the sun when at certain altitudes. 



We are introducing, for the roof of a conservatory now building, glass 

 prepared expressly by slightly grinding, from which the best of results are 

 expected. The frosting of the roof, if done in a proper manner and with 

 the proper materials, does not obstruct the light sufficiently to affect the 

 growth in winter, but breaks up the tendency to burn or scorch on a bright, 

 sunny day. Under this arrangement, mosses and ferns of a tender nature 

 grow and thrive luxuriantl}'. 



In case it would not be desirable to place the greenhouse in a position 

 where the furnace could be used in the cellar of the dwelling, the ground 

 under one of the wings might be excavated to receive the boiler, and floored 

 over ; the smoke to be brought up and carried out through the centre house 

 by a blind chimney made of cast-iron drain-pipe. In such a case, the finial 

 at top to be dispensed with, and a. crown used instead, which shields the pipe 

 form view outside, and inside takes the form of a column to support the roof. 



In the arrangement of the heating, provision should be made that each 

 apartment can be operated independent of each other, so that the orchid 

 and hot house may receive heat without the others. 



The cost of such a house would be about fifteen hundred or two thou- 

 sand dollars, exclusive of the heating apparatus. If the glass were frosted, 

 the expense would be slightly increased. Jiluch also would depend upon 

 the size of the wings. J^. A. Lord. 



SVRACUSB. N.Y. 



