256 POPULAR SCIENCE MONTHLY 



of one part by volume." The rest of the tests which must be applied 

 and to which the denaturants must conform are not of general interest. 



As the presence of denaturing agents prevents the use of the alco- 

 hol in numerous processes, other countries have long lists of substances 

 used to partially denature alcohol destined for use in particular indus- 

 tries, partially protecting it, as it were, in transit from the factory in 

 which it is made to that in which it is consumed. For instance, in 

 France, alcohol intended for use in the manufacture of aniline dyes 

 may be denatured by adding to 50 liters of the alcohol 50 liters of 

 nitro-benzene or of nitro-toluene, and 10 grams of sodium hydroxide 

 dissolved in 20 liters of alcohol. For varnishes, the product put on 

 the market must contain 75 grams of resin per liter. There are in all 

 about fifty different processes allowed for partial denaturing for as 

 many special purposes. In Germany, for the manufacture of polish, 

 alcohol may be denatured with one half of one per cent, of turpentine ; 

 for the manufacture of varnish, with 20 per cent, of a solution of one 

 part shellac in two parts of alcohol; for the manufacture of the anes- 

 thetic, ethyl ether, and numerous other medicinal substances, with 10 

 per cent, of ethyl ether; for the manufacture of acetic acid, or vinegar, 

 with 6 per cent, or 8 per cent, of acetic acid; for the manufacture of 

 smokeless powders, 1 per cent, of camphor; and so on through a list 

 as long as that in France. 



Partially denatured alcohol never wholly leaves the watchful care 

 of the guardians of the law. No list of partial denaturants permissible 

 in this country has been determined upon. Interested parties are in- 

 vited to make their suggestions and requests and these will be consid- 

 ered by the commissioner of internal revenue. 



Uses of Denatured Alcohol 



Every one knows from actual experience how clean and convenient 

 spirit lamps are. There is never any soot nor smelly oil to be cleaned 

 up, lamp chimneys remain clear and transparent and wicks require no 

 trimming. The products of the combustion of ethyl alcohol are water 

 and carbon dioxide, absolutely odorless and as harmless as any prod- 

 ucts of combustion can possibly be. It is much less inflammable than 

 gasoline, and therefore safer. Water thrown on burning alcohol will 

 immediately extinguish the fire, as alcohol is soluble in water in all 

 proportions, while water thrown on burning oil or gasoline only makes 

 matters worse. Oil and gasoline are lighter than water and are not 

 soluble in it, so they float on top and continue to burn; throwing on 

 water only spreads the fire. 



Measured in terms of units of heat, calories, a given weight of ethyl 

 alcohol is about twice as effective as an equal weight of petroleum. Its 

 convenience, cleanliness, safety and adaptability to almost any sort of 



