178 



COALFIELDS AND COLLIERIES OF AUSTRALIA. 



AVhen the coke ovens now in course of construction are 

 completed, this colliery will own 107, with an aggregate 

 weekly capacity of 1200 tons. The ovens are charged twice 

 a week, one charge being left in three days, the other four. 



The coke ovens are rectangular in cross-section, with an 

 arched roof. Each oven is 15ft. long, 6ft. Gin. wide at, the 

 ram end. and 6ft. 9in. wide at the exit end. The height from 

 floor to crown of arch is 6ft. 4in. The ovens are 2ft. 2m. 

 apart, and have 2ft. 2in. cover overhead. They are built of 

 common brick lined with fire brick, the whole being well 

 braced with buck-staves and tie rods. There is one stack 

 having an inside area of 10 sq. ft. for each pair of ovens, con- 



Fig. 111. Coke Ovens. 



nection being made by flues, each having its own damper. 

 There are two circular feed holes in the crown of each oven, 

 20in. in diameter, the bricks for which are wedge shaped, both 

 side and endways. The doors to the ovens consist of an iron 

 frame built up inside with bricks, holes being left for air, 

 which are stopped up temporarily when desired to restrict: 

 the admittance of air. The doors are raised and lowered by 

 means of an hydraulic ram (Fig. 110), which moves a rope 

 backwards and forwards as desired. A wire cord enables a 

 man on the top of a bank of ovens to open or close the valve 



