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.

    26/606 (page 10)
    It was about this time that Boyle published in the form of a letter to his nephew, Lord Dungarvan, his “ New Experiments Physico-Mechanical touching the Spring of Air and its Effects, made for the most part in a new Pneumatical Engine.” Shortly after Boyle had turned his attention to physical science he heard of a book “published by the industrious Jesuit Schottus, wherein it was related how that that ingenious gentle¬ man, Otto Gericke, Consul of Magdeburg, had lately practised in Germany a way of emptying glass vessels by sucking out the air at the mouth of the vessel plunged under water.” Boyle at once recognised that important results might be expected to follow the study of the phenomena of the air’s rarefaction, but he also saw that such results could scarcely be furnished by Yon Guericke’s method. He accordingly sought to devise a more perfect form of instrument, and with the assistance of Robert Hooke, a man of remarkable in¬ ventive powers, he, about the year 1658, contrived his “ Pnuematical Engine.” It consisted of a large pear-shaped vessel holding about thirty wine-quarts, fitted with a stopper at the top and connected at the bottom with a brass cylinder in which was a piston worked by a rack and pinion. Between the glass vessel, “ which we,” says Boyle, “ with the glassmen shall often call a receiver for its affinity to the large vessels of that name used by chemists,” and the cylinder was a stopcock which was alternately opened and closed as the piston was worked up and down, the air from the cylinder being allowed to escape through a small hole at the top, temporarily closed by a stopper. The mode of working the pump will be obvious. “ By the repetition of the motion of the sucker [piston] upward and downward, and by