, lagging cannot be used , because it would ignite and smoulder away ; in these cases the boiler room is kept cool by air spaces formed with thin plates placed in front of the uptakes , by which a current of air is continu - ally flowing up between the uptakes and the plates , and prevents in a… … Fig . 345 . — Check Valve . Fig . 346 . — Check Valve and Plug Valve , & c . a , Valve . b , Chest . c , Cover , d , Set a , Plug valve . b , Chest . C , Screwedcover . d , Check screw . valve . E , Handle . brass valve boxes ; the seating is turned in the box , and the valve ground in , having a…
e-rara · Eisenbibliothek Schlatt · No known copyright restrictions. Free to use for anything.
![An illustration from [Volume I.], leaf 492](https://img.insideoutlibrary.com/img/1024/erara-31314765-492-1.webp)
