338 On the Leniting Point of Petroleum. 
lature of this country has wisely ordered) 25 & 26 Vict. cap. 
66) that large quantities of crude petroleum shall not be 
stored within fifty yards of a dwelling house or warehouse 
except under license ; and the Act states that “ Petroleum 
shall include any product thereof that gives off an inflam- 
mable vapour at a temperature of less than one hundred 
degrees of Fahrenheit’s thermometer.” That is to say, re- 
fined petroleum, such as is commonly vended in retail shops 
as “ Crystal Oil,” “ Photogen,” “ American Paraffin Oil,” &c., 
&c., for illuminating purposes, must not be kept in or near 
a house in larger quantities than forty gallons, unless proof 
is forthcoming that it does not give off inflammable 
vapour below 100° F. If it will stand this test, then the 
liquid is not petroleum within the meaning of the Act, and 
the owner of it runs no risk. I have purposely characterized 
this Act as wisely framed, because some have questioned 
the wisdom of placing restrictions on the sale of petroleum 
and its products, (refined petroleum and petroleum spirit), 
while naphtha, spirituous liquors, knives, razors, and still 
more dangerous things, are freely bought and sold without 
any such restriction. It must be remembered, however, 
_ that the danger attending the use of these things is well 
known, and therefore always guarded against, whereas not 
only was petroleum a new article to the public, the dangers 
attending the use had to be learned, but, worse still, it was 
introduced as a lamp-oz/,—an article of unknown and dan- 
gerous properties was called by the name of an article of 
known and safe properties. Petroleum, infinitely less dan- 
gerous in itself, became, by the false colours under which it 
sailed, far more dangerous than gunpowder; that is to say, 
there was far greater chance of accidents occurring by it 
than by gunpowder. I say that, under these circumstances, 
restrictions on its sale were wisely made, and will be wisely 
retained until the character of petroleum is thoroughly well 
recognised. 
The Act having been passed, and having come into opera- 
tion (Oct. 1, 1862), merchants, brokers, and other dealers in 
large quantities of petroleum, became commendably anxious 
to buy and sell only that quality of refined article which 
should give off no inflammable vapour at temperature below 
100° of Fahrenheit’s thermometer. But, unfortunately, an 
egregiously wrong method of determining this point crept 
into the trade. To ascertain the quality, it was, and still is, 
usual to pour a little of the liquid into a saucer, small bowl, 
or other similar vessel, to apply heat by a lamp, by partially 
