VOL. XLIII.J PHILOSOPHICAL TRANSACTIONS. I69 



its flying away: the gunpowder then being wanned in a spoon, the electrical 

 flashes fire the inflammable vapour, which fires the gunpowder; but the time be- 

 tween the vapour firing the powder is so short, that frequently they appear as the 

 same, and not successive operations, wherein the gunpowder itself seems fired by 

 the electricity; and indeed the first time this experiment succeeded, the flash 

 was so sudden and unexpected, that the hand of the assistant, who touched the 

 spoon with his finger, was considerably scorched. So that there seems a 4th in- 

 gredient necessary to make gunpowder readily take fire by flame ; and that such a 

 one as will heighten the inflammability of the sulphur. 



In common cases, the lighted match, or the little portion of red-hot glass, 

 which falls among the powder, and is the result of the collision from the flint 

 and steel, fires the charcoal and sulphur, and these the nitre. But if to these 

 3 ingredients be added a 4th, viz. a vegetable chemical oil, and gently warm 

 this mixture, the oil, by the warmth, mixes intimately with the sulphur, lowers 

 its consistence, and makes it readily take fire by flame. 



A Proposal to bring Small Passable Stones Soon and with Ease out of the Bladder. 

 By the Rev. Stephen Hales, D.D. W 477, p. 502. 



Dr. H. having been present, Feb. 4, 1744-5, when the late Earl of Orford, 

 after having taken for 2 months Dr. Jurin's lixivium, voided at once 1 1 pretty 

 large nearly cubical fragments of larger stones, which were involved in coagulated 

 blood and urine ; and, a few hours after, 1 5 more at once, in the same manner, 

 in all 32 that day; some of which were as large as were possibly passable; it 

 hence immediately occurred to him, that all passable stones which have lately 

 fallen from the kidneys into the bladder, or which have broken off" from larger 

 ones, might readily and easily be brought out thence, by conveying into the 

 empty bladder, by a catheter, some very mucilaginous substance, such as syrup 

 of marsh-mallows, or a solution of gum Arabic, or barley-water. Such sub- 

 stances would bring the stones away soon, and with great ease to the patient; 

 and so not only prevent much teasing pain, by fruitlessly endeavouring to bring 

 them away with the weak force of thin urine, but also effectually to secure the 

 patient from the danger of their growing too large to come away, by long con- 

 tinuing in the bladder. And what strongly evinced the reasonableness of this 

 proposal is, that on opening the bladder of his lordship, there were no stones 

 found remaining, except 2 small grains, which were involved in the folds in the 

 neck of the bladder. 



If on trial any stones shall be found too large to pass off^ the patient is but 

 where he was before; and if any shall be of such a size as to enter the urethra 

 but part of the way, they may be pushed back, or cut out, according as their 

 situation shall happen to be. 



