400 Miscellaneous Intelligence. 



Four firemen made these experiments, and they agreed in saying, 

 that they felt no difficulty in respiring. A very abundant perspira- 

 tion came on in consequence of the high temperature to which they 

 had been exposed, but no lesion of the skin took place except in 

 one instance, where the man had neglected to secure his neck by 

 fastening the asbestos mask to the body dress. 



No one present could resist the striking evidence of defence af- 

 forded when they saw the armed man traversing the undulating 

 flames, frequently hidden altogether from view by them as they 

 gathered around him. 



The fact that in M. Aldini's apparatus a man may respire in the 

 middle of the flames is very remarkable. It has often been proved, 

 by anatomical examination, that in cases of fire many persons have 

 died altogether from lesions of the organs of respiration. It would 

 appear that the triple metallic tissue takes so much of the caloric 

 from the air as it passes to the lungs, as to render its temperature 

 supportable ; and it is known, by experiments in furnaces, that a 

 man can respire air at 120 or 130° C. and even higher. Perhaps 

 also the lesions referred to may have been due to aqueous vapour, 

 which is often produced in great abundance in fires where endea- 

 vours are made to extinguish them by water, for such vapour would 

 transfer far more heat to the lungs than mere air. Hence in every 

 case, and however guarded, firemen should enter houses in flames 

 with great prudence, because the circumstances are not the same 

 as in the experiments just described. 



It is remarked that several suits of this defensive clothing should 

 be provided, not to clothe many persons at once, but that, in en- 

 deavouring to save persons or valuable things in cases of fire, the 

 fireman should not approach again and again in heated clothing, 

 but have a change at hand. The Grand Duke of Tuscany has 

 ordered six suits for the city of Florence. 



M. Aldini shewed several experiments relative to the extinguishing 

 power of his preparations before the Societe de Physique de Ge- 

 neve. One consisted in placing an asbestos cloth of loose texture 

 over a flame either of wax or alcohol ; the flame was intercepted as 

 well as it could have been by a piece of wire gauze. This experi- 

 ment is supposed to favour the objections made to Sir H. Davy's 

 explication of the theory of the wire gauze safety-lamp ; but there 

 seems to be a mistake in the idea which has been taken of that 

 theory. Sir H. Davy never explained the effect of his lamp by 

 absorption of heat from flame dependant upon the good conducting 

 power of the tissue alone, but by the joint action of absorption and 

 radiation. There is no doubt that cloth of asbestos is an admirable 

 radiator, and that this power, with its conduction, is probably 

 sufficient to explain the effects upon Sir H. Davy's theory. — 

 xli. p. 333. 



13. Astronomy, — It was mentioned in a former number of this 



