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tenderly, are apt to shun, as supposing it un-wholsome, because cool; not considering, thata hot, close, foul Air is, in reality, the un-wholsome Air. This Experiment succeedsbest at the Door of a Chamber in which theAir is warmed by a Fire, or by Persons beingin it for some time. The Endeavours, there-fore, to prevent the Admission of any freshexhilerating Air, by double Doors, listingCrevices, be. are doubtless wrong, and isoften the Occasion of a dispiriting smokyAir in Rooms. When it is considered howsmall the Quantity of Air in the Head of aCradle is, for a Child to breathe to and fro,can it be thought salutary to confine it veryclose, not only with a Lining, but also withCurtains. Were a Child to breathe thatsmall Quantity of Air as close confin’d as ina Box, it would doubtless be smother’d in afew Hours.

441. Mr. Tidd, Clerk of her Royal High-ness the Princess of JVales's Spicery-office, hascontrived a Method to admit fresh Air intoa Room, in a commodious Way, by takingout the middle upper sash Pane of Glass, andfixing in its Place a Frame-box, with aroundHole in its Middle, about six or seven Inches

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