GREEN-HOUSE STRUCTURES. log 



pipes were there. There are scores of kinds of hot-water 

 boilers in use, and our opinion is repeatedly asked as to 

 the relative merits of many of them. This can only be 

 determined by a comparative test, which we have never 

 had time or inclination to try. We have used the boilers 

 made by Hitchings & Co. for the past twenty years with 

 the most satisfactory results. There may be better, but 

 we do not know it, and do not care to take the risk of 

 experimenting. 



HEATING BY FLUES. 



For beginners with small means, when personal atten- 

 tion can be given to the fires, by heating green-houses 

 with flues a great saving in cost can be made ; in fact, 

 nearly half the cost of construction ; for we find that the 

 hot-water heating apparatus usually is half the cost of 

 ordinary commercial green-houses, while if heated by 

 flues the cost would not be more than ten per cent, of 

 the whole. A new method of constructing flues, (or 

 rather a revived method, for it originated in 1822,) has 

 been in use for the past few years, which has such mani- 

 fest advantages that many now use it who would no doubt 

 otherwise have used hot-water heating. Its peculiarity 

 consists in running the flue back to the furnace from 

 which it starts and into the chimney, which is built on the 

 top of the furnace. As soon as the fire is lighted in the 

 furnace, the brick-work forming the arch gets heated, 

 and at once starts an upward draft, driving out the cold 

 air from the chimney, which puts the smoke flue into 

 immediate action and maintains it ; hence there is never 

 any trouble about the draft, as in ordinary flues having 

 the chimney at the most distant point from the furnace. 



By this plan we not only get rid of the violent heat 

 given out by the furnace, but at the same time it insures 



