98 BRICKWORK. 



The cost of a retort-house, of the dimensions before given from the ground- 

 line, will be as follows : 



*. d. 



Outside walls and centre portion as high as the firing-floor, in- 

 cluding cast-iron girders, York landings for firing-floor, coal- 

 stores, etc. 1975 

 Wrought-iron roof - 320 

 Brickwork for ovens, including the setting of 150 retorts, etc. 600 

 Chimney, 120 feet high 180 



3075 



In the design for a retort-house, many things must be taken into considera- 

 tion. The principal circumstances that will guide the builder in the construc- 

 tion are, first, the nature of the soil, upon which will depend the depth of the 

 foundations, the number of footings, etc. : in made earth and marshy ground 

 it is necessary to build upon a bed of concrete, composed of five parts of river 

 ballast, or gravel, free from argillaceous matter, and one part of ground lime 

 mixed intimately together with water, and thrown into the trench from a 

 height of some feet. Secondly, the builder must consider the extent of the 

 funds upon which he has to draw. This, of course, is an important point, 

 and it is a merit if he gives the " most for the money" without exceeding the 

 estimate : upon this latter consideration will depend the arrangement of the 

 ovens, coke-cellar, and coal-stores. 



The capacity of a coal-store should be accurately ascertained, and made 

 fully equal to hold eight weeks' consumption of coal in the winter season, 

 especially in those situations where it is carried by water ; because, during 

 severe frosts, canals are often rendered impassable for that period. I do not 

 refer to the neighbourhoods where coal abounds where sometimes the pit- 

 mouth is not a mile from the works ; but to those districts where coal is 

 valuable, and difficult to be obtained except through the regular channels. 



A ton of coal will occupy a space of 42 cubic feet : therefore in an esta- 

 blishment, such as that at page 101, which produces 117,000 cubic feet of gas 

 in twenty-four hours, the stores should be capable of holding 756 tons of coal, 

 or have a cubical content of 31,752 feet between the entrances. This, how- 

 ever, is seldom if ever attended to ; stores are generally made to contain about 

 three weeks' consumption, the excess being stacked outside the house and 



