PREVENTION AND EXTINGUISHMENT OF FIRES. 157 



6. Heat enough to communicate fire to adjoining inflammable substances 

 may be generated by the slaking of lime and the rapid fermentation of damp 

 manure, leaves, hay, etc., when piled in large heaps. 



7. Freshly burned charcoal is said "to have the property of absorbiDg 

 moisture, and rapidly condensing it in its pores, generating thereby so much 

 heat that it is set on fire." 



7. Several instances have been published by the American Journal of 

 Science, one of our most reliable scientific periodicals, of combustion taking 

 place in old heaps of wood ashes that had not been added to or disturbed 

 in any way for months before. 



9. It is believed by some of the best chemists that the oxidation of iron 

 rods or pipes passing through or in contact with wood-work has resulted in 

 spontaneous combustion and the ignition of the wood. 



10. Several cases of conflagration on land and sea have been reported as 

 caused by the concentration of the sun's rays upon inflammable substances 

 within apartments by means of mirrors or panes of ordinary window glass. 

 Whether these cases can be properly classed among those of spontaneous 

 combustion may be questionable, but the 'knowledge that fires can be"gener- 

 ated in this way may lead to the solution of some very mysterious cases, as 

 well as warn us to avoid the possibility of such contingencies occurring. 



11. The national board of underwriters in its late meeting at New York, 

 reported against the use of petroleum as a lubricator on the ground that its 

 use was dangerous and the cause of many fires. 



This brings us to the end of my first division of the subject, and I will 

 more briefly take up that of the extinguishment of fires or conflagrations un- 

 der the following heads, viz : 



EXTINGUISHMENT. 



1. Extinguishment by means of ordinary water. 



2. Extinguishment by means of water holding in solution gases which 

 are non-supporters of combustion. 



3. Extinguishment by means of such gases applied directly to the flames 

 by machinery. 



4. Extinguishment by means of gases or vapors generated by the heat- 

 ing or combustion of certain materials with which the timbers were coated 

 or otherwise protected previously to the erection of the building. 



I. Extinguishment by means of water. As it is well known that one 

 of the constituent elements of water is highly combustible, while the other 

 is the essential supporter of combustion, and also since it is a fact that the 

 oxygen is separated from the hydrogen by passing the vapor of water over 

 iron filings heated to redness at about 1500° F, the statements published by 

 some of the Chicago and Boston paper after their great fires, that the vast 

 amount of water thrown upon the burning buildings, by its decomposition 

 and reduction to its gaseous elements, actually fed the flames, had a degree 

 of plausibility about it although probably entirely incorrect. 



