﻿THE TERPENE OILS OF MANILA ELEMI. 3 



trunk. The resin finds considerable use among the natives as an 

 illuminant, for which purpose it is rolled in a palm leaf, or better, 

 in the fibrous part of the trunk of the young coconut tree. For such 

 purposes it behaves very similarly to pine pitch, and a large torch of it, 

 used especiall}' by fishermen, gives a light which can be seen at a great 

 distance and which burns for many hours. 



As ordinarily gathered for commerce, the resin is soft, sticky, and 

 opaque, has a slightly yellow color, and a verv, agreeable odor. It has a 

 spicy, somewhat bitter taste. If left exjjosed to the air for some time, 

 it gradually hardens throughout and finally becomes brittle. The resin 

 dissolves readily and completely in ether, chloroform, and benzene, except 

 for the separation of a small amount of water which it contains and also 

 a very small amount of a white, granular substance. In acetic ester, 

 acetone, ligroin, methyl and ethyl alcohol it does not dissolve completely 

 unless sufficient solvent is used. With these solvents a white, crystalline 

 residue remains which, with the use of alcohol in limited quantity, 

 amounts to about 25 per cent of the total. This insoluble, crystalline 

 portion of elemi resin has been the subject of considerable study and will 

 be referred to again briefly in this paper. Very soft Manila elemi contains 

 a considerable amount of water, less than 5 per cent however, while that 

 which has collected on the tree for a length of time contains very little. 



Elemi oil.- — The volatile portion of elemi resin designated as elemi 

 oil has long been known to chemists. It is generally obtained by steam 

 distillation of the resin. Gildemeister and Hoffman state that the com- 

 mercial product is prepared from Manila elemi exclusively, although in 

 most cases where this oil has been used in chemical investigation there 

 seems to be much doubt as to its origin. At present it has little use. 



The oil was first studied by Stenhouse, 5 who prepared it by distilling the hard 

 resin with steam. The variety of resin employed is not given. He obtained a 

 yield of only 3.5 per cent of oil and gives its boiling point as 166° and its 

 specific gravity as 0.852 at 24°. His analysis showed the oil to be oxygen-free. 

 Deville 6 found that the percentage of oil obtained from the resin depended upon 

 whether it was fresh and soft or had become hardened by long contact with the 

 air. From resin of good quality he obtained 13 per cent of oil. He describes 

 the oil as having a specific gravity of 0.849 at 11°, an index of refraction of 

 1.4719 at 14°, and a rotation of — 90°. 5. The product boiled very constantly at 

 174° and analysis showed it to contain no oxygen. By treating the oil with 

 hydrochloric acid gas he obtained a crystalline substance which was optically 

 inactive but concerning which he obtained no further data. No statement is 

 made concerning the origin of the resin which he used. 



In 1888, Wallach T detected phellandrenc in elemi oil but does not mention the 

 source of the oil. Shortly afterwards Wallach s studied the oil more carefully, and 

 in this case also does not state the origin of the oil with which he worked. It 



'"Ann. Ghent. (Liebig) (1840), 35, 304. 

 "Ibid. (1849), 71, 352. 

 7 Ibid. (1888), 246, 233. 

 & Ibid. (1889), 252, 102. 



