156 APPENDIX, 
The Sultan derives no inconsiderable portion of his revenue from 
this source, since the duty is levied at 30 per cent. ad valorem, thus 
_ placing tothe Sultan’s credit for the present year nearly, if not 
quite, $400,000. 
Besides the clove buds, the stems are also gathered, and form an 
article of commerce, commanding about one-fifth of the price of 
cloves and having about the same percentage of strength. To this 
circumstance is due the fact that ground clove can frequently be 
purchased in the market at a lower price than whole cloves. 
For the past fifteen years the cultivation of cloves has been the 
chief occupation of the Arab planters, and has always netted good 
returns. It seems probable that it will continue to be a profitable 
crop, since the consumption of the article appears to keep pace with 
the inevitable increase of production, 
Up to the present time the plantations have been worked with 
slave labour at comparatively small expense; but with stoppage of 
slave supplies from the mainland, great difficulty will be experienced 
by the planters during harvest time. One result will be an increase 
in expenses; but what the planters have most to fear is that the 
curtailment of the labour-supply will entail a direct loss by rendering 
it impossible to harvest the crop until after it has blossomed, when 
it would be unfit for the uses of commerce. 
Oil of Cloves. 
The value of this oil depending upon the quantity of eugenol 
present, H: Thoms proposes the following method of assay, depend- 
ing upon the formation of benzoyl-eugenol (see Am. Jour. Pharm., 
1891, 406): 5 gms. of the oil, 20 gms. solution of sodium hydrate 
(15 per cent.), and 6 gms. benzoyl chloride are placed in a tared 
beaker of 150 cc, capacity and thoroughly mixed, this causing the 
mixture to become quite hot; after cooling 50 cc. water are added 
and heat applied until the crystalline mass melts, and again allowed 
to become cold; the clear liquid is run through a weighed filter (dried 
at 101°C.), and the same operation of washing the crystals repeated 
twice with 50 cc, water. ‘To remove the sesqui-terpene, which may 
contaminate the benzoyl-eugenol, the crystals have to be washed 
with alcohol ; this is effected by adding to the still moist crystalline 
mass in the beaker 25 cc, alcohol of 90 per cent,, warming until 
solution is effected, rotating the solution until the crystals begin to 
