FORM OF STRUCTURE. 



371 



latter plan, great economy would be effected, for the arrangements could 

 be so contrived that the plants might be elevated or lowered according to 

 circumstances, and thus the expense saved of carrying up the roof to an 

 extraordinary height, which should be avoided as much as possible, not 

 only on account of the extra expense in the first erection, but also in the 

 great expenditure of heat ever after. 



This mode of arrangement has been exemphfied in the new houses 

 recently built in the Jardin des Plantes, at Paris. The space where 

 the tubs and pots stand is sunk six feet under the ground level, which is 

 tantamount to adding the same to the height, besides the improvement 

 in the appearance. In this ca^ity the plants should be placed on stands, 

 by which they could be elevated or lowered at pleasure. There can be 

 no objection to this mode of arrangement, provided that a sufficient 

 temperature be kept up at and round the roots of the plants, and that a 

 sufficient degree of ventilation be afforded : without these precautions the 

 plant would not flourish. This can, however, be very easHy effected by 

 making the arrangements for heating sufficiently low, so that the bottom 

 of the pit or cavity may be heated fii'st. 



Upon a smaller scale many of the lower grov^ing Tropical Fruits may 

 be cultivated in houses not very materially different from those in general 

 use ; and, perhaps, the most economical of all might be such as is 

 represented by the accompanying diagram, and in which many of these 

 fruits might be grown. 



Snch a house, if not exceeding thirty or thirty-five feet in length, might 

 be heated by one flue, or hot-water pipe, placed at a, over which a treUised 

 table should be placed for the reception of young plants, to replace such 



