414 ODOEOGllAPHIA. 



absorbed by the oil. One c. c. of decinormal thio-sulphate is 

 equivalent to 0-008 grm. of bromine. It is absolutely necessary 

 not to expose the mixed bromine solution and essential oil to the 

 action of daylight, but gaslight has no sensible effect. The time, 

 15 minutes, must be adhered to, or secondary reactions occur, 

 vitiating the result. Finally, the temperature should be as near to 

 lo^'o C. as possible, and should on no account be above 17^"5 C. or 

 below 15^-0 C. 



AVorking in this way my results are as follows : — 



Xo. 1 ... ... ... ... ... 70'9 per cent. 



Ditto about 9 months later ... ... 65-8 „ 



Xo. 2 70-5 



Xo. 3 88-2 



Xo. 4 108-0 



Finally, I draw attention to the following points : — 



Sample Xo. 3 does not a])feaT to be wholly English oil. 



Generally speaking, the sp. gr. of English oil is higher than 

 that of the foreign. 



English oil is more soluble in spirit than foreign. 



The colour reactions of the oils are similar, although scarcely 

 identical, but of little value for distinguishing the oils. 



The Ijromine absorption of English oil is much lower than 

 that of the forei«;n. 



YoL. I., p. 224. 



Cloves. A recent Consular report* supplies the following 

 useful information on the Clove cultivation in Zanzibar (the most 

 important cultivation of that island) : — 



" The clove tree (a native of the Moluccas) was introduced into 

 Mauritius in 1770 by the French, and at the end of the century 

 an Arab accompanied a French officer from Zanzibar to Bourbon 

 and obtained permission to take back a small quantity of seeds 

 and plants with him. This was the commencement of the clove 

 cultivation in Zanzibar, the Arab making the lirst plantation at 



* No. 266, 1892. 



