36 



which have the most liberal supply of air. — 

 Those who doubt the propriety of an almost con- 

 stant ventilation will, by referring to the description 

 of Mr. Crawshay's houses, as described by Dr. 

 Lindley, find that very much of Mr. C.'s success is im- 

 puted to the circumstance of open laps. It has been 

 said that, shut up a house how we will, there is still a 

 circulation, and undoubtedly there is ; but is it suffi- 

 cient? For, after all, how different the sensation 

 between breathing in a shut -up house and in the open 

 air. So important do we consider ventilation that 

 we use it night and day on all possible occasions. 

 It must be remembered, however, that a very small in- 

 gress and egress is sufficient where there is so great a 

 disparity of temperature between the outer and inner 

 atmospheres. One great desideratum remains to be 

 accomplished in this respect, and that is to circulate 

 and promote motion in the atmosphere, and avoid 

 unnecessary extremes of heat, without dissipating the 

 atmospheric moisture. All new modes of heating 

 should, in combination with the question of economy, 

 combine this most important consideration. 



There have been many modes suggested for self- 

 acting ventilators, descriptions of which may be 

 found in Loudon's Encyclopedia of Gardening, and 

 the Transactions of the London Horticultural Society; 

 but there are none that can supersede the gardener's 

 personal care, directed by the thermometer and ex- 

 perience. 



