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of this is made apparent by the pungent smell. And yet this 

 is not always a safe or invariable rule, because oils from differ- 

 ent localities differ in nothing so much as in odor. And oils 

 from these different localities equally well, and honestly re- 

 fined, will still possess some of the peculiarities of their crude 

 condition. The only safe guide for dealers and consumers 

 of this article, is the temperature at which it will inflame. 

 Let it always be insisted on, that the point at which it shall 

 inflame shall be at least 120°. An instrument has been in- 

 vented for determining this point. Its introduction and 

 general use will be an important check upon manufactur- 

 ers, and a great security to those who deal in and use it. 



