411 



founded on the hypothesis that the ultimate atoms of all matter 

 have a pyramidal figure. 



15. " An Experimental Inquiry into the Modes of Warming and 

 Ventilating Apartments." By Andrew Ure, M.D., F.R.S. 



The Author, having been consulted by the Directors of the 

 Customs Fund of Life Assurance, on the mode of ventilating the 

 Long Room in the Custom House, and deeming the subject one of 

 great public interest, was induced to lay the result of his observa- 

 tions and experimental inquiries before the Royal Society. In this 

 room, about two hundred persons are busily engaged in transacting 

 the business of the Institution. All these persons are found to 

 suffer more or less from ailments of the same general character, the 

 leading symptoms of which are a sense of fulness and tension in the 

 head, flushing of the face, throbbing of the temples, giddiness, and 

 occasional confusion of ideas, depriving them of the power of dis- 

 charging their duties, in which important and frequently intricate 

 calculations are required to be gone through. These symptoms of 

 determination of blood to the head are generally accompanied by 

 coldness and languid circulation in the feet and legs, and by a feeble, 

 and frequent, as well as quick and irritable pulse. On examining 

 the air of the room by appropriate instruments, the author notices 

 more especially three circumstances in which it differs from the ex- 

 ternal air : first, its temperature, which is maintained with great 

 uniformity within a range of 62° to 64°; secondly, its extreme dry- 

 ness, which, on one occasion, measured by Daniell's hygrometer, 

 was 70 per cent. : and thirdly, its negatively electrical state, as in- 

 dicated by the condensing gold-leaf electrometer. In all these 

 qualities the air respired by the inmates of the room bears a close 

 resemblance to the pestilential blasts of wind which, having passed 

 rapidly over the scorching deserts of Arabia and Africa, constitutes 

 the Simoom of those regions, and is well known by its injurious ef- 

 fects on animal and vegetable life. To these noxious qualities is 

 superadded, as in the air of all rooms heated through the medium 

 of cast-iron pipes or stoves, an offensive smell, arising partly from 

 the partial combustion of animal and vegetable matters always 

 floating in the atmosphere of a town, and perhaps also from minute 

 impregnations of carbon, sulphur, phosphorus, or even arsenic, de- 

 rived from the metal itself. The Author expresses his surprise that 

 in the recent report of the Parliamentary Committee on the subject 

 of ventilation, no reference is made to the methods employed for 

 that object in factories, although they afford the best models for imi- 

 tation, being the results of innumerable experments made on a 

 magnificent scale, with all the lights of science, and all the resources 

 of the ablest engineers. He proceeds to describe these methods j 

 and is then led to investigate the comparative efficiency, with a 

 view to ventilation, of a draught of air resulting from a fire and 

 chimney, and that produced by the rotation of a fan-ventilator. 

 He shows that a given quantity of coal employed to impart motion 

 to the latter, by means of a steam-engine, produces a ventilating 



