HOUSES AND CONVENIENCES. 27 



if we always gave ear to her instructions the sun's rays 

 strike the earth, and produce the greatest heat at the sur- 

 face. She has no fixed confining canopy over the plants 

 under her charge to prevent the heat from passing up- 

 ward, and if we are obliged to have such, we ought not 

 to render our necessities more unnatural than there is occa- 

 sion for. Keep the head cool and the feet warm, is ad- 

 vice often given by our physicians, and the same rule 

 applies to plants generally, with very slight modifications. 



If the roof be made with sashes to slide over each other, 

 which is the method best adapted for removal of the 

 house at any future time, the upper ones will become the top 

 ventilators ; but when it is fixed, and composed of a con- 

 tinuous row of sash bars over supporting rafters underneath, 

 the openings require to be lifted up from the bottom, and 

 hung on the opposite end by hinges, or suspended by the 

 middle on each side, and opened on a pivot. When hung 

 by hinges the sides may rest upon the rafters, and the 

 lower end project a little over the next squares of glass, 

 thereby making it proof against drip, and this is perhaps 

 the best plan, for beside being safer against rain, air can 

 be admitted and the temperature lowered, without cold 

 draughts striking down into the house. If hung from the 

 sides there are no effectual means of capping, and however 

 good the joints may be, the rain will find its way through 

 more or less in time of violent storms. 



The internal fixings required, are wires to support 

 the vines, a tank to hold water while being tempered in 

 the house, a hose with a pipe attached to distribute 

 the water, and a force-pump to supply the hose. The 

 wires are most convenient when placed parallel with the 

 sash-bars, and about fifteen inches below the glass, which 

 will be sufficient to clear the leaves from contact ; if less 

 space is allowed, the foliage of vigorous vines will touch 



