88 Of the Management of Fire 



From the top of this cover an open wooden tube 

 (m> Fig. 17), about 12 inches in diameter, rises up per- 

 pendicularly, and going through the roof of the brew- 

 house ends in the open air. This tube, which is 

 furnished with a wooden damper, is intended to carry 

 off the steam. 



On the side of this cover next the mashing-tub, as 

 also on that opposite to it, by which the wort runs off 

 into the coolers, there are large folding wooden doors 

 (i and k, Fig. 1 7), which are occasionally lifted up by 

 means of ropes which pass over pulleys fastened to the 

 ceiling of the brewhouse. 



There are likewise two glass windows (see Fig. 1 7) in 

 two opposite sides of the cover, through which, as soon 

 as in consequence of the boiling of the liquid the steam 

 becomes transparent and invisible (which happens in a 

 very few minutes after the liquid has begun to boil), 

 the contents of the boiler may be distinctly seen and 

 examined. 



Whenever there is occasion during the boiling to 

 open either a door or a window of the cover, it is neces- 

 sary to begin by opening the damper of the steam- 

 chimney, otherwise the hot steam, rushing out with 

 violence, would expose the by-standers to the danger of 

 being scalded ; but when the damper of the steam- 

 chimney is open, no steam comes into the brewhouse, 

 though a door or window of the cover be wide open. 



Another similar precaution is sometimes necessary 

 in opening the door of the fire-place, which it may be 

 useful to mention. When the dampers in the canals 

 by which the smoke goes off into the chimney are 

 nearly closed (which must frequently be done to confine 

 and economize the heat), if, without altering the dam- 



