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SPONTANEOUS COMBUSTION. 



The following article on the causes and prevention of ea>;es of spontaneous com- 

 bustion in barns and stables written by me in response to the enquiries of a corres- 

 pondent, was published in the pages of the Canadian Live Stock and Farm Journal. 

 The importance of the subject to the ftxrmers throughout the Dominion is such 

 that no apology will be needed for its insertioa here. 



" SPONTANEOUS COMBUSTION." 



" Combustion, as it is ordinai-iiy known and recognized, is the chemical com- 

 bination of combustible matter with the oxygen of the air, the union of the two 

 being accompanied by the giving out of heat and light. When the union takuo 

 place rapidly the heat evolved is intense, but when slowly, the heat produced may 

 be almost imperceptible — though the sum total of the heat produced may be the 

 same in both cases. Combustion may therefore occur without the phenomenon of 

 flame — as flame is really burning gas, which, for its generation from ordmary com- 

 bustible material and ignition, requires a somewhat intense heat. The heat of our 

 bodies is maintained by a process of slow combution, i.e., evolution of heat unac- 

 companied by flame, through the union of the organic matter of our food with the 

 oxj'gen of the air we breathe. 



" Spontaneous combustion (or ignition of inflammable material without contact 

 with flame) occurs when the union of the oxygen (oxidation) is sufficiently rapid to 

 i-aise the temperature to the ignition or burning point of the inflammable substa' ce. 

 The first great requisite of combustion is air — or rather the oxygen of the air. 

 Woollen and cotton rags saturated with oil are capable of absorbing oxygen rapidly, 

 and in consequence of which have their temperature raised to the ignition point — a 

 comparatively low temperature for such material. Very many well-known and 

 authenticated instances are on record of this character as causing fire in the holds of 

 vessels and in manufactories. Dust, formed by the deposition of organic matter in 

 an exceedingly fine state of division, often causes, in like manner, fires in woollen and 

 grist mills. 



''The spontaneous fires which break out in hay-stacks, barns, manure piles, etc., 

 are all due to this same process of oxidation, and are caused by the inflammable 

 material being damp — moisture greatly assisting slow combustion. Fermentation 

 may be considered as one of the many forms of combustion. It is a process in which 

 the decomposition of the material is brought about by bacteria — microscopic plants 

 always present in the air — whose development requires moisture and warmth. By 

 their growth more heat is generated, until that point is reached at which the mate- 

 rial upon which they feed takes fire. Fermentation is the principal agent in causing 

 spontaneous ignition in barns, outhouses, etc. 



" There are other causes besides those given above for spontaneous combustion. 

 A not infrequent one is the slaking of lime. Two instances have come under my 

 notice in which barrels of quicklime, left uncovered in a leaky building, have become 

 slaked by the rain, the heat generated by the operation of slaking — really a chem- 

 ical combination of the lime with the water — being sufficient to ignite the surround- 

 ing woodwork. The prevention in such cases as these it is not necessary to enlarge 

 Upon. As to those instances in barns, etc., in which the fire is caused by damp hay 

 or clover, I would say, if possible, do not store it damp, and see that the roof is 

 water-tight or tlie stack well thatched. If, however, cii-cumstances necessitate the 

 putting away of the hay moist, salt it well. Salt is a preventative of fermentation, 

 and consequently of heat. If, in spite of these precautionary measures, heat begins 

 to generate in the mow, ventilation should be resorted to, so that the heat as it is 

 developed may be carried oil', and not allowed to accumulate or become so intense as 

 to raise the hay to its burning temperature. In the case of manure piles, it is a wise 



