536 PHILOSOPHICAL XKANSACTIONS. [aNNO 1732. 



the same time; which happenetl a few weeks before she perceived the swelling 

 and pain in her pelvis; and probably this might be the cause. As the constric- 

 tion of the lower parts by the cold water might, in a great measure, impede 

 the fluids circulating through the lower parts, and the blood being at the same 

 time rarefied and expanded by the heat, might therefore burst through the 

 more tender lymphatics, and produce the extravasation. 



Furthe? Experimenta concerning Electricity. By Mr. Stephen Gray. N° 423, 

 p. 285. 



In N" 422 Mr. Gray gave an account of experiments, showing that water 

 will be attracted by electric bodies, and have an electric virtue communicated 

 to it, so as to attract solid ones; and since then he has been on another inquiry, 

 viz. Wliether there might not be a way found to make this property of elec- 

 trical attraction more permanent in bodies.? How far he has succeeded in this 

 attempt, vvill appear by the following experiments made on several bodies; and 

 as they were all prepared after the same maimer, excepting N" 18 and ig, which 

 will be described afterwards, a general description of the method of preparing 

 and preserving them in a state of attraction, may suffice. 



The bodies on which the experirfients were made, were, rosin both black and 

 white, stone-pitch, shell or gum-lac, bees-wax, and sulphur. He procured 3 

 iron ladles of several sizes, in which tie melted these substances, in due quan- 

 tities. When any of these bodies were melted, they were taken oft" the fire, 

 and set by in the ladle to cool and harden ; then it was returned to the fire, 

 where it remained until it was melted about the bottom and sides of the ladle, 

 so as to be moveable; so that by inverting the ladle, it might be taken out; 

 having the form of nearly the section of a sphere, the convex surface, as also 

 the plane one, being naturally (as it were) polished, excepting the sulphur, 

 which cools without retaining its polish, except when cast in glass vessels. 



When any of the substances were taken out of the ladle, and their convex 

 surface hardened, they would not at first attract, until the heat was abated, or 

 until they came to a certain temper, and then there was a small attraction ; 

 which warmth he estimated to be nearly that of a hen's egg when just laid: the 

 attraction increasing so, as when cold, to attract at least 10 times further than 

 at first. 



The manner of preserving them in a state of attraction, was by wrapping 

 them up in any thing that would keep them from the external air; as at first 

 for the smaller bodies he used white paper, but for the larger ones white flainiel ; 

 but afterwards found that black worsted stockings would do as well. Being 



