OLEUM CAJUPUTI. 279 



quoted earlier than 1813, when the price given is Ss. to Ss. 6cL per 

 ounce, with a duty of 2s. 4^tZ. per ounce. 



Manufacture — In the island of Bouro, in the Molucca Sea, the 

 leaves of the Kayii-puti or Aij-puti, i.e. White-u'ood trees, are sub- 

 mitted to distillation with water, the operation being conducted in the 

 most primitive manner, as already witnessed, about the year 1792, by 

 Labillardifere in his celebrated voyage with Laperouse. Bickmore,^ an 

 American traveller who passed three months in the Lsland in 1865, 

 states that it produces about 8,000 bottles of the oil annually, and 

 that this is almost its only export. The Trade Returns of the 

 Straight Settlements published at Singapore, show that the largest 

 quantity is shipped from Celebes, the great island lying west of Bouro. 



Description — Oil of Cajuput is a transparent mobile fluid, of a 

 light bluish-green hue, a fragrant camphoraceous odour, and bitterish 

 aromatic taste. It has a sp. gr. of 09 2 6, and remains liquid even at 

 (8°6 F.) — 13° C. It deviates the ray of polarized light to the left. On 

 diluting it with bisulphide of carbon it becomes turbid. 



Chemical Composition — The researches of Schmidl (1860) and 

 of Gladstone (1872) have shown that cajuput oil consists chiefly of 

 Hydrate of Cajiiputene or CajupiUol, C^"H^^,H-0, which may be 

 obtained from the crude oil by fractional distillation at 174° C. If 

 it is repeatedly distilled from anhydrous phosphoric acid, Cajupidene, 

 G^^W^, passes over at 160-165° C; it has an agreeable odour of 

 hyacinths. After the cajuputene, Isocajujnitene distils at 177°, and 

 Paracajuputene at 310-316°, both agreeing in composition with 

 cajuputene. 



Like most essential oils having the formula C^^ff®, crude cajuput 

 oil is capable of forming the crystallized compound C^^^H^^, SOH^. This 

 we have abundantly obtained by mixing 4 parts of the oil with 1 of 

 alcohol 0830 sp. gr., and one part of nitric acid 120 sp. gr.; the mix- 

 ture should be allowed to stand in shallow dishes. By adding 1 vol. 

 of absolute alcohol to 3 vol. of cajuput oil, and saturating it with 

 anhydrous hydrochloric gas, crystals of the compound C^'^H^^HCl)^ 

 may be obtained. By vapour of bromine the oil acquires a beautiful 

 reen colour. 



K 1 part of iodine be gradually dissolved in cajuput oil, the 

 temperatiu-e being maintained at 50° C, fine green crystals of 

 (C^'*H^TII)^OH- are formed. They may be recrystallized from very 

 little glacial acetic acid, but will not keep for more than a few weeks. 



The green tint of the oil is due to copper, a minute proportion of 

 which metal is usually present in all that is imported. It may be 

 made evident by agitating the oil with water acidulated by a little hydro- 

 chloric acid. The compounds of copper with inorganic acids being com- 

 paratively of a fainter colour than the cupric salts of organic acids, 

 the aqueous solution of chloride of copper now formed displays no 

 longer the fine green tint. To the solution, after it has been put into 

 a platinum capsule, a little zinc should be added, when the copper will 

 be immediately deposited on the platinum. The liquid may be then 

 poured ofi" and the copper dissolved and tested. When the oil is 

 rectified, it is obtained colourless, but it readily becomes green if in 

 ^ Travels in the East Indian Archipelago, Lond. 1868. 282. 



