J 364 



ENCYCLOPAEDIA OF AGRICULTURE. 



SUPPLEMENT. 



are, perfect ease in filling and emptying, without the necessity of handling either the heated vessel, or 

 food ; nearly a maximum capacity with a minimum cooling surface to the vessel ; perfect staunchness, 



durability, and readiness of examination and 

 cleansing of the interior. If there be no other 

 elevated supply of water to the steam kitchen, a 



Eump should be fixed in it, both to supply the 

 oiler and to wash the vessels ; potatoes, especi- 

 ally, leave a kind of slime upon the inside of steam 

 tubs, which soon putrifies. It is said the cattle 

 are sometimes choked by small potatoes, which 

 are not sufficiently steamed ; this might be pre- 

 vented by the addition of a pair of rollers, into the 

 hopper of which the cylinder might discharge its 

 contents ; and they would bruise all to a given 

 size, and deliver into the truck before mentioned. 

 Fig. 1192. is a side elevation of the cylindrical 

 vessel for steaming hay, chaff, bran, oats, clover, 

 &c. It is of a much larger size than the cylinder 

 for steaming more solid matters ; and, therefore, 

 is not made of wooden staves, but of iron plate 

 riveted together like a steam boiler. Fig. 1194. is 

 a cross section of the same : the letters of reference 

 apply to both figures alike. The cylinder is sup- 

 ported on four vertical frames of cast iron, a a, 

 properly connected by diagonal stays ; one end of 

 it is riveted in, and through it the steam-pipe b 

 enters. The other end is moveable, and closed 

 by a circular lid or cover, also of boiler plate, se- 

 cured by six cotter bolts, as shown in elevation, 

 fig. 1193. ; it is strengthened round its edge by a 

 ring of two inches and a half angle iron riveted 

 on, and is externally slightly convex : c is the 

 convex false bottom, formed of sheet iron one 

 eighth of an inch thick, punched full of round 

 holes three tenths of an inch diameter, and stif- 

 fened by ribs of T iron, riveted to its lower side : 

 d d are two siphon tubes for emission of con- 

 densed water, as before described: e is a man- lid 

 for the purpose of filling in chaff, &c, or other 

 such matters. The large end lid has got a coun- 

 terbalance weight attached to the chain /. The 

 whole of this cylinder, and all the steam-pipes, 

 are lapped over with slight haybands, which are 

 lapped over with thick felt or dreadnought; and 

 this, lastly, is sewed tightly over with strong sail 

 canvass painted. This mode of uniting, as a coating, several bad conductors having different con- 

 ducting powers, is found to resist the passage of heat much more effectually than an equal thickness of 



even the worst conductor of the three. This fact, which,' I believe, has not been hitherto noticed, will 

 at once suggest to the scientific reader some curious analogies to the passage of sound through media 



