700 PHILOSOPHICAL TRANSACTIONS. ''' [aNNO 1775. 



are almost universally effected in that part of the body which is formed with the 

 most subtle organization. ; iy»od- ' 



The heated room will, I hope, in time become a very useful instrument in 

 the hands of the physician. Hitherto the necessary experiments have not been 

 made to direct its application with a sufficient degree of certainty. However, 

 we can already perceive a foundation for some distinctions in the use of this un- 

 common remedy. Should the object in view be to produce a profuse perspiration, 

 a dry heat acting on the naked body would most effectually answer that purpose. 

 The histories of dropsies and some other diseases, supposed to have been cured 

 by such means, are well known to every physician. In some cases also, a moist 

 heat^ and in others heat transmitted through a quantity of clothes, might have 

 their peculiar advantages. That the danger likely to ensue from such applica- 

 tions is less than has been commonly apprehended, our former experiments gave 

 sufficient reason to believe; and the same was amply confirmed by those which 

 make the subject of this paper. For during the whole day, we passed out of the 

 heated room, after every experiment, immediately into the cold air, without any 

 precaution; after exposing our naked bodies to the heat, and sweating most vio- 

 lently, we instantly went out into a cold room, and staid there even some minutes 

 before we began to dress; yet no one received the least injury. I felt nothing 

 this day of the noise and giddiness in my head, which had affected me in making 

 the fonner experiments; and, whether from the force of habit, or any other 

 cause, the shaking of our hands was less, and we felt less languor, though the 

 heat had been so much more intense. 



XLVIll. A Proposal for Measuring the Attraction of some Hill in this Kingdom 

 by Astronomical Observations. By the Rev. Nevil Maskelyne, B. D., F. R, S., 

 and Astronomer Royal, p. 495. 



If the attraction of gravity be exerted, as Sir Isaac Newton supposes, not only 

 between the large bodies of the universe, but between the minutest particles of 

 which these bodies are composed, or into which the mind can imagine them to 

 be divided, acting universally according to that law by which the force which 

 carries on the celestial motions is regulated ; namely, that the accelerative force 

 of each particle of matter, towards every other particle, decreases as the squares 

 of the distances increase; it will necessarily follow, that every hill must, by its 

 attraction, alter the direction of gravitation in heavy bodies in its neighbourhood, 

 from what it would have been from the attraction of the earth alone, considered 

 as bounded by a smooth and even surface. For, as the tendency of heavy bodies 

 downwards, perpendicular to the earth's surface, is owing to the combined at- 

 traction of all the parts of the earth on it, so a neighbouring mountain ought, 

 though in a far less degree, to attract the heavy body towards its centre of at- 



