MECHANICAL VENTILATION ON THE DOWNDRAUGHT SYSTEM, BY IMPULSION, OR THE 'PLENUM' PRINCIPLE, APPLIED TO SCHOOLROOMS.
<ul><li><b>A</b> Roof Ventilator.</li>
<li><b>B</b> Main Upcast Shaft.</li>
<li><b>C</b> Horizontal Foul Air Trunk.</li>
<li><b>DD</b> Connecting Pipes from Foul Air Flues.</li>
<li><b>EE</b> Foul Air Flues.</li>
<li><b>FF</b> Foul Air Exits into Flues EE.</li>
<li><b>GG</b> Fresh Air Supply Flues through which the air is mechanically projected at a high velocity up on to the ceiling and then descends, escaping at Exits FF into Flues EE.</li></ul><p>N.B. The fresh air supply heated to such a temperature, as is necessary to effectually warm a building, is thereby seriously deteriorated for breathing purposes, therefore to secure healthy ventilation the heating of a building should always be separate and distinct from that of the air supply.
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<ul><li><b>BLUE</b> Fresh air supply.</li>
<li><b>YELLOW</b> Products of combustion.</li>
<li><b>BROWN</b> Products of respiration.</li>
<li><b>RED</b> Products of respiration from infected scholars.</li></ul>
Robert Boyle &amp; Sons
Natural &amp; Artificial Methods of Ventilation