THE TECHNOLOGIST. 



EXPLOSIBILITY OF COAL OILS. 



BY T. ALLEN. 



So recent has been the introduction of coal oil into general use for 

 burning in lamps, that few persons have as yet had satisfactory oppor- 

 tunities of obtaining a knowledge either of its peculiar properties or 

 of the peculiar processes lately invented for extracting oil from coal 

 in quantities sufficient to constitute a new and important article of 

 commerce. 



Some of the qualities of coal oil sold in the market having proved 

 dangerously explosive, the directors of fire insurance companies have 

 become alarmed, and have increased the rates of fire insurance on pro- 

 perty where such oil is stored or burnt in lamps, deeming it to be 

 extra hazardous, like camphine and " burning fluid." But a manifest 

 difference being discoverable in the inflammability of the oils sup- 

 plied from different establishments, it is evident that some mode of 

 distinguishing the safe from the unsafe oils has finally become indis- 

 pensable for the security of the insurers as well as for the satisfaction 

 of the insured. Accordingly, in compliance with a request of the 

 board of directors of the Rhode Island Mutual Fire Insurance Com- 

 pany, the following investigations have been made to determine, by 

 practical experiments, the comparative explosibility of coal oils, and 

 the consequent probable danger of the use of them in lamps for 

 lighting manufactories and dwellings. 



Several of the experiments may appear to be very simple ; but as 

 they serve to exhibit instructive facts for popular information, they 

 are none the less valuable for dispelling unfounded fears of danger, and 

 for inducing due caution where there may exist causes for alarm. 



All the liquid products of the distillation of coal are popularly con- 

 TOL. IV. I 



