630 Fire and Water, as applied to Plant Culture. 



as cold as an anchor in the bottom of the sea. The boiler of 

 this apparatus has, however, at last got burnt through, after a 

 tormenting trial of three years, and put the finishing stroke to 

 this the most unnecessarily intricate and impracticable apparatus 

 for heating that ever I have seen. From the contraction and ex- 

 pansion of his exposed boiler, a crack emitted smoke more or 

 less all round it, especially when the draught was checked ; which, 

 by the by, was done by a handsome cast-iron scientific damper, 

 with an index hand and notched wheel, half-way up the chimney. 



I have worked some very excellent boilers of Bailley's, and 

 only complain of the large fire-bricks, called Welch lumps, 

 placed at the sides of the fire, instead of making the boiler form 

 the sides of the furnace : not only do these Welch lumps in the 

 course of time get burnt out, and require to be renewed, but the 

 heat that goes to burn them is lost to the hot- water pipes. How- 

 ever, there is no impracticability about Bailley's boilers, nor 

 any intricacy about any part of his apparatus ; every thing is 

 simple, substantial, and efficient, and the quality of the work- 

 manship is not to be surpassed. 



I have seen Weeks's boilers, composed of wrought-iron tubes 

 fastened into semicircular cast-iron heads, and covered in with an 

 arch of brickwork ; on which arch, I should say, the principal 

 part of the heat of the fire was expended, since the flame only 

 passes through two rows of tubes, in the same manner as it would 

 through the bars of a gridiron ; but, as I never worked one of 

 these, I would not venture an opinion on their practical ope- 

 ration from hearsay. 



The most extraordinary boiler I ever saw was being set up the 

 other day at a member of parliament's seat, in the vicinity of 

 London. It was, in shape, like a huge hat of cast-iron, and con- 

 tained nearly four-score gallons ; and, being very thick, its weight 

 was almost incredible. This was a Mr. H.'s idea of a boiler; 

 and, much against the will of the men who were setting it up, and 

 the gardener who had to set it to work, and whose reputation it 

 would affect, it was ordered to be erected in the place of another 

 of the same improved, or rather unproved, cast, which had been 

 pronounced a failure, and pulled down. 



So much for a few of the best of the various systems of heating 

 by hot water, and one (at least in my opinion) of the worst. 

 Now, if (gardeners would be kind enough to favour the world with 

 a full and unbiassed account of the merits and demerits of the 

 systems of heating which they have pi'actically proved, it would 

 tend much to advance the science of gardening ; as it must be 

 very discouraging indeed for ladies and gentlemen, as well as 

 gardeners, to have their plant-houses injured by the weather, 

 from the want of a sufficient supply of heat, and every now and 

 then to have them pulled to pieces for repairs, when it is well 



