Proiecfwn of Persons from Fire. 115 



after it may have been extinguished by the wire gauze, there must be 

 imminent danger of asphyxia ; and that if no difficuky of breathing 

 ensues, a purer air must find access to the men, and this he con- 

 ceives may occur in several ways. 



1. It is certain that the men have not their heads constantly in the 

 flame, which we know moves v/ith the gentlest current, and thus af- 

 fords moments favorable for respiration. 



2. Admitting that the men remain too long in the flames to breathe 

 freely, wp must then conceive that fresh air may rise between the two 

 tissues not in contact, and thus supply the respiration. Besides, it is 

 not difficult to hold one's breath thirt}^, sixty, or even more seconds, 

 and though we do not think that the firemen resorted to this in pass- 

 ing along the hedges of flame, the short time requisite to walk ten 

 yards renders it possible. 



But although in the open air, or in a free space, respiration may be 

 effected without danger, it is certainly to be feared that in a confined 

 situation, filled with smoke, which it is so common to meet with at 

 fires, it would not be possible to breathe freely, though protected by 

 the armor. Would it not be advisable then to provide a portable re- 

 servoir of fresh air, or a flexible tube descending from the mouth to 

 the floor, where the purest air is generally to be found. The reporter 

 insists on this point, for nothing so much interferes with respiration as 

 a dense smoke. It w^ould be well for firemen to exercise themselves, 

 like divers, in holding their breath. 



Amianthus is found more abundantly, especially in Corsica, than it 

 was formerly supposed ; and since Madame Lena Perpenti of Como 

 has succeeded in making various qualities of tissue, and even lace, of 

 this material, it cannot be doubted that this mineral may be used for 

 the various operations of spinning and weaving, but it must always 

 bear too high a price to admit of extensive applications. Hence 

 woollen cloth properly prepared is to be preferred, and when well 

 impregnated whh sal ammoniac and borax it does not take fire, and 

 may even be calcined without communicating combustion, and is also 

 a slow conductor of heat. In this latter respect it has even the ad- 

 vantage of amianthus, as has been shewn by M. Hourens. There- 

 forCj in point of economy, of facility of preparation, of convenient 

 use, of lightness, and of slower conducting pov^er, wool is preferable 

 to amianthus, — and its resistance to flame, though incomparably less 

 than that of the mineral, is nevertheless great enough to answer as a 

 substitute for the latter in almost all the circumstances of ordinary fires. 



