TREATMENT OF WOUNDS 35 



Natural asphalt comes largely from Trinidad and 

 Venezuela. Artificial or residual asphalts are dis- 

 tilled by several firms, notably Byerly & Son, of 

 Cleveland, who call their product " Byerlite." 

 The Barber Asphalt Company markets natural 

 asphalt in many forms. The most generally use- 

 ful solid form is their bituminous cement No. 143. 

 The writer prefers it to the artificial forms. Both 

 cost thirty dollars a ton. The solid forms of as- 

 phalt can be used just as they come, being melted 

 for use. There are serious difficulties, however, 

 about applying hot preparations to tree wounds, 

 particularly if the wounds are high up in a tree. 

 Most forms which need melting, also, dry too 

 brittle to be perfectly effective. To avoid these 

 drawbacks, the asphalt is usually fluxed with some 

 liquid in which it will dissolve, just enough of the 

 solvent being used to bring the mixture to the 

 proper consistency. Many substances are used 

 for this purpose, including gasoline, petroleum 

 oils of various consistencies, linseed oil, and other 

 vegetable paint oils. 



The mixture can be bought ready made or can 

 be made by the user. The most available com- 

 mercial products are various water-proofing com- 

 pounds, used in laying water-tables in masonry 

 work. The heaviest of these materials should be 

 chosen, and those should be avoided which are 

 fluxed with gasoline or benzine, for the resultant 



