ELEMI. 



149 



Canarium, is very tall and large, that it is called by the Spaniards 

 Arhol de la hrea, and that it yields an abundance of odorous resin 

 which is commonly used for pitching boats. Living specimens of the 

 tree together with samples of the resin were brought to Paris from 

 Manila by the traveller Perrottet about the year 1820. For the last 

 twenty years the resin has been common, and is now imported in large 

 quantities ^ for use in the arts, so displacing all other kinds. It has 

 been adopted as the Elemi of the British Plmrmacopma (1867), and is 

 in fact the only variety of elemi now found in English commerce. 



Description — Manila elemi is a soft, resinous substance, of granular 

 consistence not unlike old honey, and when recent and quite pure is 

 colourless ; more often it is found contaminated with carbonaceous 

 matter which renders it grey or blackish, and it is besides mixed witli 

 chips and similar impurities. By exposure to the air it becomes harder 

 and acquires a yellow tint. It has a strong and pleasant odour suggest- 

 ive of fennel and lemon, yet withal somewhat terebinthinous. When 

 moistened with spirit of wine, it disintegrates, and examined under the 

 microscope is seen to consist partly of acicular crystals. At the heat of 

 boiling water the hardened drug softens, and at a somewhat higher 

 temperature fuses into a clear resin. 



Chemical Composition — Manila elemi is rich in essential oil. 

 Oq submitting 28 lb. of it to distillation with water, we obtained 2 lb. 

 13 oz. (equivalent to 10 per cent.) of a fragrant, colourless, neutral oil, of 

 ?P-gr. 0-861 at 15° C. Observed in Wild's polaristrobometer we found 

 It to be strongly dextrogyre.' H. Sainte Claire Deville' on the other hand 

 Ijas examined an oil of elemi that was strongly levogyre. ^ This 

 discrepancy shows that there are among the oils of various kinds of 

 elemi, differences similar to those existhig in the oils of turpentine and 

 copaiba. By the action of dry hydrochloric acid gas, Deville obtained 

 from his oil of elemi a solid crystalline substance, C^ff ' + 2 HCl. We 

 lailed to produce any such compound from the oil of Manila elemi. Our 

 oil of elemi dissolves in bisulphide of carbon ; when mixed with concen- 

 trated sulphuric acid, it becomes thick and assumes a deep orange colour. 

 . % submitting the crude oil to fractional distillation, we separated it 

 into six portions, of which the first five were dextrogyre in gradually 

 jiinumshing degree, while the sixth displayed a weak deviation tothe 

 ^f- The first portion having been dissolved in four times its weight 

 f strong sulphuric acid, washed and again distilled, exhibit a deviation 



to the left. 



480 



•c(iual to about 



■ I observed the following deviations :- , , ,. ^,.^. 



In a column of 25 millimetres from 47^*5 to 70^'5 (deviation 2.S ). 



:: :: Z :: :: 43-o(2i+9o=92o-i).-f.a.f. 



.fe;<W,«,xii,(lS41)184.. , . _ 



to the rhjlit. 



»> " 



-/-•- /.ewtiW, XU. (1S41) 184. .„. . 



"etollowing deviations were observuLl, in a column of '2o milUnietres : 

 ; ^>1 distilled at 172°— 180° C. from 47° '6 to 74° '5; deviation 2b '9 t 



180°-1S3° „ 7F-2 „ 23° -6 



183°-184°-5 , 68°-S „ 21°-2 



5 „ 184°-195° .. 65° -8 „ 18° '2 



3. 



J5 



Ll'i€^?^ >-"?- --^- ' :: 4G°-2 :: i°-4totho./^ 



■""1 47° -G to m". 



