330 



FORCIFG GARDEN. 



Fit(. 35. 



tf— 1 



^ 



circulation lias been adopted in some of tlie principal 

 nursery gardens near London. 



Mr. Charles H. J. Smith, garden architect, in a com- 

 munication to the Scottish Horticultural Society, has 

 clearly shown that the system of heating by the circula- 

 tion of hot water in metallic pipes is easily applicable, 

 not only to any glazed house constructed with flues, but 

 to any select portion of an existing fruit-wall, although 

 already clothed with peach, vine, or fig-trees. In the 

 last case, a small furnace and boiler are, of course, placed 

 at the back of the wall ; the expanding water rises to a 

 cistern near the top of thewall; horizontal pipes, mak- 

 ing three or four turns, are inserted into the south front 

 of the wall (which is an easy operation, as the w^all is 

 usually faced with brick); and through these the water 

 circulates, to the groat increase. of the temperature of 

 the air surrounding the tree. The operation should be 

 accomplished late in the autumn ; the tree being care- 

 fully unnailed, bent forward, and secured from injury 

 or breaking, and as carefully replaced. 



Mr. A. Perkins has constructed an apparatus of small 

 tubes hermetically sealed, in wdiich water circulates, of 

 a temperature varying from 300° to 400° Fahrenheit. 

 The contrivance is very ingenious, and has been pretty 

 extensively employed at London and Edinburgh, in 

 heating public offices and warerooms; but as the opi- 



