1 90 Description qfSajig's Uj/psomeier. 



Having thus related to you our success, I shall now en- 

 deavour briefly to describe the apparatus by which it is effected. 



The boiler is placed in the back shed, and is made of copper, 

 and weighs 80 lbs. with the taps included. It is furnished with 

 a safety valve, a tap and funnel at the top to pour in the water, 

 a tap at the bottom to let out the water, another to show when 

 there is water in sufficient to allow room for steam to be generated, 

 and a tap at the top with a small pipe attached which nearly 

 reaches down to the bottom of the boiler. This last is to show 

 when the water is too low, which it does by permitting steam to 

 escape, which would not be the case so long as the end of the 

 attached small pipe was covered with water. 



The pipe that conveys the steam into the houses is IJin. 

 diameter ; it rises from the boiler 3 ft., and is then carried through 

 the back wall down to the floor inside under the back stage ; it 

 then branches right and left to each end of the houses ; is then 

 led across each end, and on the front ; the branches on the ends 

 and front being reduced to 1-inch pipe. In those pipes, and also 

 on the back, are holes drilled every 6 ft., into which holes small 

 pipes 6 in. long are screwed. These small short pipes are in 

 the form of the letter T, to throw the steam horizontally, so as 

 to diffuse it through the air before it I'eaches the pots or plants. 



We soon found the small pipes on the main back one were 

 not necessary, as the steam spread itself from the front and ends 

 quite sufficiently for our purpose. The cost of fuel for this ap- 

 paratus is but trifling, and the steam and the pipe that contain it 

 heat the houses so much, that a very considerable saving of coals 

 in the hot-water boilers is the consequence. We have therefore 

 attained two objects ; the supplying of moisture to the internal 

 atmosphere most effectually, and a saving of fuel. 



The boiler and pipes and fitting up cost about \3L; but, if we 

 had had an iron boiler instead ot copper, it would not have cost 

 more than 10/. 



The question now is, whether the above method is worthy of 

 imitation. All I can say on the matter is, that both Mr. Erockle- 

 hurst (my spirited employer) and myself are perfectly satisfied 

 with it, and I shall be happy to give any further information to 

 you or an}'^ of your readers who may require it. 



Fence, Macclesfield, Cheshire, Feb. 15. 1840. 



Art. IV. Description of the Hypsometer, an Instrument invented by 

 John Sang, Esq., Land- Surveyor, fo?' taking the Heights of Trees, 

 Buildings, and other Objects. Communicated by Mr. Sang, 

 Land-Surveyor, Kirkcaldy. 



I HAVE taken the first leisure hour to make you the instrument 

 for measuring the height of trees and buildings which I men- 



