m 



VIRGIN GUM. 21 



of the manufactured or smoked article from Para, has remained 

 at about the same, varying from eighteen to thirty cents per 

 pound, according to its quality. It may be important to state 

 here, that although some of the trees, like some animals, yield 

 richer milk than others, this difference in price is not owing 

 to any real difference, in the quality of any particular variety 

 of gum, but depends on the degree of cleanliness, the age of the 

 gum, or the length of time it has been gathered, as there is 

 more gum in the same weight when it has been well dried, 

 there being less moisture in the old, than in the new gum. 



The third variety is that which is known in the United 

 States as virgin gum. This flows spontaneously from the roots of 

 the tree, and forms ill-shapen masses of from five to thirty 

 pounds weight. The tree is the same as that which yields the 

 second variety in South America. When well seasoned, or 

 dried, it makes the best goods, and is more readily metallized 

 or vulcanized than the other varieties. It contains ninety parts 



carbon and ten parts hydrogen, its specific gravity . It 



is dissolved by the same solvents as the other two varieties, but 

 it is not so easily acted upon by them. When this gum has 

 acquired great age, it is nearly impossible to dissolve that which 

 is obtained from the oldest trees. 



The virgin gum is of a much harder nature than either of the 

 other two kinds. After being kept for several years it becomes, 

 for a considerable depth beneath the surface, nearly as hard as 

 horn or whalebone. The other kinds appear to season, and 

 become more solid for about two years, and not to change 

 materially afterwards. 



The virgin gum was formerly imported into the United States 

 at one-third the present price of the bottle and shoe gum, but 

 for some years past it has not been much exported from Para. 

 This fact, the writer is of opinion, is satisfactorily accounted for, 

 in the chapter under the head of " method of gathering the gum," 

 page . 



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