Hot-7iouses by hot Water. 



37 



muiiicatcs, by means of the upright tube h, with the open vessel c, and the 

 lowermost is connected in a similar manner by means 

 of the tube d, with one or any number of tubes under 

 the level of the boiler at e. The uppermost of the tubes, 

 at e is connected by the tube /with the open vessel c. 

 Now, all these tubes being so connected as to admit of 

 water circulating freely through them, when a fire is 

 made in a, the heated water ascends by its rarification 

 into the open vessel c ; and its place in the tubes round 

 the fire is supplied by the colder water from e, through 

 d', the heated water descending to supply its place from 

 the open vessel e, by the tube /. The object gained by 

 this arrangement is, the circulation of water below the 

 level of the boiler, the limits of the depth below being 

 that of the height of the open vessel above. To pro- 

 duce this circulation, it is not necessary that the water 

 should boil ; for, as every heated particle will ascend to 

 the open vessel c (which might be closed, and then the 

 apparatus would be in principle the same as that of 

 Mr, Perkins), its place must be supplied by a cold par- 

 ticle from d. When the fire is urged so as to raise 

 the water in the open vessel nearly to the boiling point, 

 the circulation goes on with the greatest rapidity. 

 I V m e It may be observed, that the substitution of tubes 



V^^^l^j^ round the fire for a boiler over it, is by no means 



necessary for the success of this plan, though by tubes 

 the rapidity of the circulation is greatly increased. Any close boiler 

 with the tube h attached to its cover, and communicating with an open 

 vessel fixed at any height, such as c, having another tube, similar to f, 

 affixed to it, will circidate the heated water from such vessel to a point 

 below the bottom of the boiler, nearly equal to the balance of atmo- 

 spherical pressure, or, say 30 ft. below it. Messrs. Cottam and llallen, 

 and Mr. Timothy Bramah, have both circulated hot water on a large 

 scale upon this principle, which is clearly laid down in Count Cha- 

 bannes's pamphlet ; and in our review of it, Vol. IV. p. 28. If the 

 reader will turn to p. 30. of that review, he will there find an engraving, 

 in which a is the close boiler, answering to Mr. Weekes's tubes ; h, the 

 ascending tube; e, the open vessel, answering to Mr. Weekes's open 

 vessel; and d, the descending tube, answering to Mr. Weekes's tube,/. 

 We mention this, not to undervalue Mr. Weekes's apparatus, but merely 

 to show that the principle has been known and acted upon since 1818. 

 Mr. Weekes, who is one of the most ingenious men we know, has re-invented 

 both the principle and the application of it ; and most sincerely do we wish 

 him the success he so amply deserves. His plan is capable of varied and 

 useful application, both in heating garden structures and dwelling-houses, 

 manufactories, &c. The tubes may be small, even as much so as those of 

 Mr. Perkins ; in which case, as the water circulates with very great rapidity, 

 Mr. Weekes's plan, like that of Mr. Perkins, may be adopted in situations 

 where large pipes would be unsightly. 



There is one objection, however, to all plans of boilers composed of 

 tubes, which is, that, as they cannot be cleaned out, they soon become 

 coated with deposit in the inside ; and, consequently, extremely difficult to 

 heat. An extrs-application of fire then becoming requisite, the tubes or 

 boilers are soon burnt out. For immediate and striking effects, there is 

 no plan equal to the tube system ; but, for permanency, none are equal to 

 the open boiler, or close boiler with a manhole, having a cover that admits 

 of easy removal, for cleaning out the interior. We have seen so many 



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