. Ventilation for dwellings, rural schools and stables. Fig. 11.—The respired airtends to remain at thebottom. become extinguished. As the airis forced continually into the jarit becomes gradually filled and thelighted candle has taken the posi-tion represented in Fig. 12. Buteven here, if breathing into thejar is continued, the flame will beextinguished as the out-coming re-spired air surrounds the candleand shuts off a fresh supply fromthe flame. Clearly, then, air once i^^^- V--^^ fh<me is extin- . ^ . gnished even when held breathed is not suitable for respir- above the mouth of the jar
. Ventilation for dwellings, rural schools and stables. Fig. 11.—The respired airtends to remain at thebottom. become extinguished. As the airis forced continually into the jarit becomes gradually filled and thelighted candle has taken the posi-tion represented in Fig. 12. Buteven here, if breathing into thejar is continued, the flame will beextinguished as the out-coming re-spired air surrounds the candleand shuts off a fresh supply fromthe flame. Clearly, then, air once i^^^- V--^^ fh<me is extin- . ^ . gnished even when held breathed is not suitable for respir- above the mouth of the unless much diluted with pure Continuous Flow of Air is Necessary. 17 A CONTINUOUS FLOW OF AIR IS NECESSARY. Since once-breathed air is not suitable for respirationuntil much diluted with that which is pure it follows thatinto and out of dwellings, schools, churches and stables, solong as they are occupied, must be maintained a sufficientand continuous flow of air to bear away that whose foodvalue has been reduced and to restore an equal volume ofthat which is pure. Let us again use the two-quart Masonjar. Fig. 9, for another demon-stration. AVith the candle restingon the bottom and the mouth ofthe jar unobstructed the flameburns with a steady uniform bril-liancy. By holding the hand aboveits mouth a strong ascending cur-rent may be distinctly felt, butsuch a continuous up-going cur-rent of air from out the jar canonly be possible when an equalcountercurrent is maintained andit is this which sustains the flow. Now, with the candle still barn-ing in the jar let these in-goingand out-going currents be com-pletely st
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectventilation, bookyear
