Volume 2

Essays in historical chemistry / by T.E. Thorpe.

  • Thomas Edward Thorpe
Date:
1902
Catalogue details

Licence: Public Domain Mark

Credit: Essays in historical chemistry / by T.E. Thorpe. Source: Wellcome Collection.

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    opportunely turning the key [of the stopcock] and stop¬ ping the valve [the brass peg inserted into the cylinder] as occasion requires, more or less air may be sucked out of the receiver according to the exigency of the experi¬ ment and the intention of him that makes it.” Before describing his experiments in detail Boyle proceeds to “ insinuate that notion by which it seems likely that most if not all of them will prove explicable, namely, that there is a spring or elastical power in the air we live in. By which elater or spring of the air, that which I mean is this: that our air either consists of, or at least abounds with, parts of such a nature, that in case they be bent or compressed by the weight of the incumbent part of the atmosphere, or by any other body, they do endeavour, as much as in them lieth, to free themselves from that pressure, by bearing against the contiguous bodies that keep them bent; and, as soon as those bodies are removed, or reduced to give them way by presently unbending and stretching out themselves, either quite, or so far forth as the contiguous bodies that resist them will permit, and thereby expanding the whole parcel of air these elastical bodies compose.” Boyle pictured to himself this process of unbending and stretching by considering the air near the earth to be “ such a heap of little bodies lying one upon another as may be resembled to a fleece of wool. For this (to omit other likenesses betwixt them) consists of many slender and flexible hairs; each of which may indeed, like a little spring, be easily bent or rolled up; but will also, like a spring, be still endeavouring to stretch itself out again. For though both these hairs, and the aerial corpuscles to which we liken them, do easily yield to external pressures ; yet each of them (by virtue of its structure) is endowed with a power or principle of self-