Page:Philosophical Transactions - Volume 024.djvu/334

Quantities that first reacht the (still Ignited) Iron taking fire, by their flame making an Explosion of the whole, at once blowing up the Recipient, altho the weight of Air incumbent on it was equal to 144 l. ⁠1/2⁠, accounting the Receiver at 3 inches ⁠1/2⁠ diameter, but was something more, which does sufficiently allow for the want of height of Mercury. The Gage then standing at 29 ⁠1/2⁠, instead of 30, from which the Calculation is made. The Gunpowder us'd was the common Glas'd sort; and the weight of the six quantities, which remov'd the Recipient, with so great a Pressure incumbent on't, was but 7 grains, each Quantity weighing something more than one. I did not observe the Recipient to be broke before it reach'd the Floor. It was thick lin'd with Sulphureous and Nitrous Steams, so that the flashes of Fire thro the Clowdiness of the Glass seem'd very much to resemble faint Lightnings. The Content of the Receiver was equal to about 25 ounces ⁠1/2⁠ of Water, allowing for the Bulk of Iron and Pedestal.

Upon making the late Experiment of firing Gunpowder in Vacuo, it was hinted as well worthy of tryal, Whether the Factitious Air of fir'd Gunpowder was endu'd with any Quality differing from Common Air. In order to the satisfaction of the Query, On December the 26th about noon I included a Candent Iron inVacuo