628 Effects of Fire and Water, 



proportions that the square feet of hot-water pipe should bear 

 to the cubic feet of air to be heated ; and it is equally certain, 

 that they are often so tied down to false economy, as not to be 

 allowed more than the cost of a certain quantity of pipe, which 

 they know to be too little : and now, for the sake of such, I will, 

 before I conclude this article, put these proportions in a practical 

 shape, from my own measurement and experience. I have just 

 now measured 'wo houses heated by Fowler of Temple Bar, 

 London, which are side by side; the one, a vinery for early 

 forcing, contains hot-water pipes to the extent of 1 square foot 

 of surface to evei'y 1 cubic feet of air to be heated, the laps of the 

 glass being closed, and only one glass gable end exposed. The 

 other house contains 1 square foot of surface of hot-water 

 pipe to every 33 cubic feet of air; and this, with one gable end 

 against a stove, defended the green-house plants from frost, 

 during the late severe winter. But, should the proprietor, at any 

 future time, turn this house to the same use as its neighbour, the 

 ironmonger certainly would not be to blame, if it did not answer 

 as well, with 230 per cent more air to heat. Another house, 

 heated by Cottam and Hallen, contains 1 square foot of pipe for 

 every 13 cubic feet of air ; but this house is exposed on all sides, 

 and occupied with early forced peaches. Another, an early 

 vinery exposed on all sides, heated by Kewley, on the siphon 

 principle and open copper boiler, has 1 square foot of pipe for 

 every 1 1 cubic feet of air. Now, I consider 1 ft. in 10 ft. necessary 

 for pines ; 1 ft. in 1 2 ft. for grapes ; 1 ft. in 1 5 ft. for peaches ; and 

 1 ft. in 24 ft. to keep the frost from green-house plants, when the 

 thermometer in the open air falls to zero : and this, I am pre- 

 pared to say, is perfectly practicable with Fowler's wrought- 

 iron boilers, in the shape of a drain tile, whose sides form the 

 furnace on all sides, thereby losing no heat. His method has 

 this superiority over every other that I am acquainted with, that 

 his narrow long furnace is equally adapted to burn with advan- 

 tage half a peck of fuel on a mild evening, or to contain at once 

 a barrowful of coals and coke mixed, on banking up for a stormy 

 night: and here consists its superiority over many which are 

 beautifully calculated to burn fuel to the greatest advantage; and 

 which, were the supply of heat to be the same at all times, would 

 certainly answer most admirably. But the case practically stands 

 thus : to counteract the midnight blast in the month of March, 

 and maintain 75° in an exposed vinery, where a valuable crop of 

 grapes is in flower, which the least chill would ruin, is a test 

 for which few of our own new-fangled apparatuses are calculated, 

 and, to do it with a small furnace, the attendant must be all 

 night at his post, like a mariner at the helm : whereas, I have 

 kindled a body of fuel on the bars of Fowler's furnace, and 

 pushed that back on a second tier of bars, which had no draught 



