as a Vehicle for conveying Heat, 49 



water 13 boiled in order to generate fleam, and which, in its 

 construction, may be made to rcfemble the boiler of a fteam- 

 engine, I fliall call the jieam- boiler: the vertical tube, which, 

 rifin«- up from the top of the boiler, conveys the fteam into 

 the tubes (nearly horizontal), which are fufpeiidcd from the 

 ceiling of the room, I fliall call ihc prime conductor : to the 

 horizontal tubes I (hall give the name of horizontal conduc- 

 tors, or (imply, conductors ofjleam: and to the (fmaller) tubes, 

 which, descending perpendicularly from thefe horizontal con- 

 due'lors, convey the fleam to the liquids which are to be 

 heated, I fliall, exclusively, appropriate the appellation of 

 fleam-tubes. 



The veflels in which the liquids are put that are to be 

 heated, I fliall call the containing veffels. Thefe veifels may- 

 be made of any form ; and, in many cafes, they may, with- 

 out any inconvenience, be constructed of wood, or of other 

 cheap materials, inftead of being made of coftly metais, by 

 which means a very heavy expenfe may be avoided. 



Each fleam- tube muft defcend perpendicularly from the 

 horizontal conductor, with which it is connected, to the level 

 of the bottom of the containing veflel to which it belongs; 

 and, moreover, mud be furniflied with a good brafs cock, 

 perfectly (team-tight; which may beft be placed at the height 

 of about fix feet above the level of the floor of the room. 



This fleam -tube may either defcend within the veflel to 

 which it belongs, or on the outfide of it, as fliall be found 

 mod convenient. If it comes down on the outiide of the 

 veflel, it muft enter it at its bottom, by a fliort horizontal 

 bend; and its junction with the bottom of the veflel muft: 

 be well fecured, to prevent leakage. If it comes down into 

 the veflel, on the infide of it, it muft defcend to the bottom 

 of it, or at leaft to within a very few inches of the bottom of 

 it, otherwife the liquid in the veflel will not be uniformly 

 and equally heated. 



When the fleam-tube is brought down on the infide of the 

 containing veflel, it mav either come down perpendicularly, 

 and without touching the fides of it, or it may come down 

 on one fide of the veflel, and in contact with it. 



When feveral fleam-tubes, belonging to different con- 

 taining veflels, are connected with one and the fame hori- 

 zontal fleam conductor, the upper end of each of thefe tubes, 

 inftead of being limply attached, by foldering, to the under 

 fide of the conductor, muft enter, at leaft one inch, within 

 the cavity of it ; otherwife the water refulting from a con- 

 denfation of a part of the fleam in the conductor, by the cold 

 air which furrounds it, inftead of finding its way back into 



Vol. X. D s tb c 



