A CHEMICAL STUDY OF THE RESINOUS CONTENTS AND THEIR DISTRIBUTION IN 

 TREES OF THE LONG-LEAF FINE, BEFORE AND AFTER TAPPING FOR TURPENTINE. 



By M. GoMBERG. 



Botanists tell us that resins are produced by the disorganization of cell walls anil by the 

 breaking down of starch granules of cells. Chemists believe that resins are oxidation products of 

 volatile oils, the change being expressed by fornnila as follows: liC,oHi6 + 3() = C!2,iHM02+ HjO. 



Whatever view be correct * one thing is certain, and that is that the formation of either resins 

 or essential oils requires the presence in the tree of those peculiar conditions which we call vital. 

 The tree nuist live, must be active, must assimilate carbon dioxide and imbibe moisture, in order 

 that oil of turpentine and rosin be formed. 



The heart of the tree is the dead part of it. It docs not manufacture any turpentine. A jiart 

 of the oleoresin in it had been formed when the heart wood was yet sap wood, and remained there 

 after the change from sap to heart liail taken place. It is also probable that the heart of the tree 

 acts as a storehouse in which there is deposited a portion of the oleoresin formed in the leaves 

 and sap. 



When a tree is tapped for turpentine there are two possible changes tliat might be supposed 

 to take place: (1) The tree may be considered as placed in a pathological condition, when it will 

 strive to ]iroduce a lai'ger amount of oleoresin in order to supply the amount removed. In a few 

 years the energy of the tree will be exhausted, and the amount freshly supplied will fall tar below 

 the amount of oleoresin drawn oft" by the tapping. The tapping will then have to be discontinued. 

 The oleoresin in the heart wood will in this case remain untouched. ('2) The oleoresin previously 

 stored away in the heart might, by some unknown means and ways, also be directed toward the 

 wound. 



If the tirst change takes place then, the tapping will have little effect ui>on the chemical com- 

 position of the heart wood. If, however, the second condition i>revails during ta])ping, then, of 

 course, the heart wood will be seriously aftected for some time after tapping, and will contain a 

 muchsnuiller amount of oleoresin than it contained before tapping. Moreover, the tapping may 

 aftect not only the amount of oleoresin, but also the quality of the new product and the relative 

 distribution of volatile and nonvolatile products. 



For this reason the chemical side of the problem has been approached by parallel analyses of 

 tapped or untapped trees for their relative amounts of turi)entine. It was hoped that by a large 

 series of analyses an average might be obtained showing whether lapped and untapped trees differ 

 from each other in that respect. 



« 



CHEMICAL COMPOSITION OF TURPENTINE. 



Under the name of turpentine is known an oleoresinous juice produced by all the coniferous 

 trees in greater or less amount. It is found in the wood, bark, leaves, and other parts of the trees. 

 It flows freely as a thick juice from the incisions in the bark. It consists of a resin or resins dis- 

 solved in an essential oil; the latter is separated from the former usually by distillation with steam. 



There are many varieties of turpentine corresponding to the different varieties of Conifera', 



* The one view does not exclude the other. 

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