108 ON THE EXPLGSIBILITY OF COAL OILS. 



appears to be sufficient reason for classing these liquids as specially 

 hazardous. 



In making experiments with the tin vessel of the capacity of a 

 common lamp (before described), a single drop of naphtha was found 

 to yield sufficient vapour to produce as much explosive action as could 

 be produced by the most inflammable coal oil for sale in the market, 

 when similarly experimented with ; and after every experiment failed 

 to exhibit the slightest explosive tendency of the best kerosene oil, 

 a single drop mingled therewith rarely failed to yield sufficient vapour 

 to manifest its presence by a slight explosive puff, when kindled by a 

 lighted match. The combustion in this case was confined to the 

 minute quantity of naphtha gas, without either kindling the kerosene 

 oil, or dangerous results. 



In all the accounts of the explosions of camphine and burning fluid 

 lamps there appear to be no statements of any damage or injury to 

 life or property by the mere mechanical force developed. The prin- 

 cipal disastrous residts are caused by the scattering about of highly 

 inflammable liquids, which instantaneously spread the conflagration 

 over surrounding combustible substances. It is sufficient to produce 

 the most disastrous consequences, if a lamp containing any of these 

 highly inflammable liquids, produce only a sufficient gust of an ex- 

 plosive character to disperse the blazing contents over the dresses of 

 adjacent persons, or surrounding combustible matter. The rapid 

 communication of the flames has in this way often proved fatal to life 

 and destructive to buildings. For this reason the rates of premium 

 for fire insurance have been enhanced on property jeopardised by the 

 use of camphine and burning fluid in lamps for lighting factoiy build- 

 ings. As the accidental fall and breakage of camphine or burning- 

 fluid lamps on a floor have often produced the loss of life and property 

 by communicating fire, as above stated, an experiment was made to 

 test the comparative results which might be anticipated from a similar 

 accident to a burning lamp containing coal oil, which required to 

 be heated to 125 deg. before it emitted sufficient gaseous vapour to be 

 kindled by a lighted match. Some coal oil of this quality was poured 

 out of a burning lamp upon a floor and the blazing wick dropped 

 therein. There it continued burning until the heat of it raised the 

 temperature of the surrounding coal oil to 125 deg., when the blaze 

 began gradually to spread over the surface of the oil on the floor in an 

 enlarging circle, but no sudden flash of flame spread over the whole sur- 

 face at once, as was the case when burning fluid and camphine were 

 similarly experimented upon. 



To represent the effect of accidentally spilling the kerosene oil from 

 a burning lamp upon a cotton dress, a piece of calico cloth was moist- 

 ened with the oil, and then held up in contact with the flame of a lamp. 

 The kerosene required a little time for its temperature to become raised 

 to the evaporative point of 125 deg., before the blaze began to spread 



