444 Description of a mode of heating Pits and Stoves. 



through them, and instead of allowing the steam to come 

 into the houses from holes being made in the chambers, as 

 above described, the chambers are made perfectly close, and 

 when steam is required in the interior of the houses, they 

 use extra pipes with a stop-cock, from the top of the boiler, 

 to convey the steam into the houses : — secondly, instead of an 

 arch, turned with single bricks, by which the chambers in my 

 houses are covered, the tops of these chambers are supported 

 by iron bars or rafters, and finished with slates or tiles laid in 

 mortar ; which I conceive not so good as a single brick arch. 

 I am, your most obedient, 



and very humble Servant, 

 William M' Murtrie. 



Shugborough Gardens, 



March 2, 1826. 



References to the Section and Ground Plan of the Pit 



1. Fire-place. 



2. Flue. 



3. Boiler and pipe. 



4. Steam chamber. 



5. Cavities to admit steam and heat, one under each light, 

 back and front, to be stopped with plugs at pleasure. 



6. Waste pipe, for allowing the steam to escape when the 

 cavities are shut. 



7. Cistern with a ball-cock for the supply of water to the 

 boiler. 



8. Piers to support stone slabs to stand upon while giving 

 air to the pit. 



