474 POPULAR SCIENCE MONTHLY. 



hundred and eighty pounds, the hard turpentine two hundred 

 and forty pounds, and pitch, thirty-two gallons to the barrel. All 

 spirits of turpentine are gauged by the inspectors of naval stores. 

 Tar and turpentine barrels are marked and certified, and usually 

 show the initials of the maker's name. 



Very few people have any correct notion of the number of 

 uses to which the products of turpentine have been put. Let us 

 mention some of the different ways spirits of turpentine enters 

 into the arts and manufactures. Many who read this article by 

 gaslight will remember when they read their newspapers by the 

 smoky light furnished by "camphene." This was before the 

 introduction and use of petroleum. Camphene is prepared by 

 mixing the rectified oil of turpentine with alcohol. Although 

 kerosene is now so cheap, the rectified spirits of turpentine is still 

 used for illuminating purposes in some backwood sections of the 

 South. 



Perhaps the most common uses of the spirits of turpentine are 

 those in the arts, where it enters into the preparation of paints 

 and varnishes, and especially in the manufacture of India-rubber 

 goods. The paint and varnish industries take about five million 

 gallons annually, while the rubber industry requires about three 

 and a half million gallons a year. 



But spirits of turpentine has other uses not so well known to 

 most readers. How many would enjoy their salad oils and other 

 vegetable oils, if they knew that they were adulterated with tur- 

 pentine oil ? How many invalids know that their medicines 

 contain spirits of turpentine, or that the liniment or ointment 

 which relieves their aches and pains is largely composed of tur- 

 pentine ? 



Quite as varied and valuable are the prodiTcts of rosin in the 

 arts and manufactures. Do you know that the finest grades of 

 rosin are used in the manufacture of paper ? How many persons 

 who look at the printer's ink on this paper would say that it con- 

 tains rosin ? How many, washing their face and hands, ever sus- 

 pect that there is rosin in the scented soap ? There is rosin in 

 all these products, as there is in sealing wax, putty and sizing, 

 and in varnishes. 



Two kinds of rosin oil are obtained from rosin by the process 

 of dry distillation. The light rosin oil is used principally in the 

 fine varnishes. The heavy oil enters into the manufacture of 

 axle grease, and machine and lubricating oils. It is one of the best 

 and cheapest lubricants for metal bearings in machinery, the 

 petroleum oils not excepted. The heavy rosin oils are largely 

 used in the preparation of cheap paints, such as are used to cover 

 metal, roofs, and so forth. 



The product called " pitch " is the residue from the dry distil- 



