me or quality ot the sound. This whistle may be changed to a fire-alarm whistle without delay by a valve which is already attached. It is provided with a piston that can be moved up or down within the bell or tube, thus changing the interior length of same and consequently also the sound of the… … secure by a jam-nut. Owing to this of a building an extension rod must be construction the lower edge of the bell attached to the piston and a rope or is always exactly in line with the slot in wire to the whistle-valve lever. the case through which the steam es- These whistles are manufactured by…
Engineering
Internet Archive · Smithsonian Libraries · Public domain (published before 1931). Free to use for anything.
