405 



Burning Lime, and. Limekilns. 



114 



sliding shutters or hinged doors, while, in the roof, there 

 should be a chim- 

 ney for the escape 

 of the smoke. It 

 will readily be 

 understood, that 

 the use of a cover, 

 whether fixed 

 or movable, is 

 chiefly to retain 

 the heat ; but 

 where the cover 

 is a fixed struc- 

 ture, and suffi- 

 ciently large, something will be gained by placing the fuel 

 and limestones there, to be dried and heated before they are 

 thrown into the kiln. 



Three fifths of the contents of the Closeburn oval kiln 

 may be drawn out every day, and when it is closed at top and 

 bottom, the fire will not go out for five or six days. 



I am, Sir, yours, &c. 

 Closeburn, January 2. 1827. J. S. Menteath. 



In the 'Register of the Arts and Sciences (vol. iv. p. 290.), 

 a description and figure is given of Heathorn's combination of 

 a limekiln and coke-oven, the object of which is to prepare 

 quicklime and coke in the same kiln by a single operation ; 

 and the arrangements to effect it are at once so simple and so 

 complete, as seemingly to preclude the capability, of any ma- 

 terial improvement. The economy of the process is likewise 

 carried to the greatest possible degree ; for that portion of 

 the coal which is separated from it to form coke, is, by its com- 

 bustion, rendered subservient to the burning of the lime- 

 stone ; and the coke, owing to its increased bulk, being nearly, 

 if not quite, as valuable as coal in the market, the expense of 

 burning is very much reduced. 



This kiln and oven are delineated as raised on a flat sur- 

 face (Jig. 115.), the lime being raised by means of a jib and 

 crane, though, like other kilns, it might be placed on the side 

 of a bank for supply in the usual manner. Those who are 

 interested in the subject may refer to the work from which 

 this account is quoted ; or to the patentee, Mr. Heathorn, 

 Maidstone, or 40. Coleman Street, London. The kiln is 

 now, and has for some time past been in full operation, at the 

 patentee's lime-works at the former place. In districts where 



