CROPS Y1EI<DING OILS, DYES AMD TANNINS 975 



The colour of the flowers, white in the alba variety, is pale sulphur and also 

 variegated in the miniata variety. The leaves are the most important part 

 used and a careful description is given, together with a series of measure- 

 ments. The commercial product is formed by the dried leaves, which are 

 rareh' whole, and are greyish green or j^ellowish brown in colour according 

 to the age of the product. Impurities are often mixed with these leaves, 

 such as pieces of branches and fruits, and debris of other plants, which must 

 be regarded as added for fraudulent purposes when found in considerable 

 quantities. 



Henna has been used from the most remote times as a dye plant by the 

 Eastern peoples : the Arabs use it as an excellent cosmetic for different pur- 

 poses and also as a medicinal plant. Its dyeing qualities are widely uti- 

 lised for wool, silk and wcod, and in Europe it is also esteemed as the 

 only really harmless vegetable dye. From an analysis of several samples 

 coming from Tripoli, the writer found that the most usual frauds and adul- 

 terations consist in the addition of fragments of fig, pomegranate, olive, 

 palm and other leaves or wood, thoroughly ground and mixed to the 

 powdered product. 



The cultivation of henna is very extensive in the fields of Tripoli and 

 is always irrigated. The plantlets are raised in nurseries and transplanted 

 in the spring, being planted in parallel rows at a distance of 50 X 50 cm. 

 Xo manure is applied. Irrigation is carried out every 6 days. The plan- 

 tation is hoed in the spring and sometimes again in the autumn, and 

 some weeding is done. The crop lasts about 12 3'ears, the maximum 

 growth being reached in the second or third year. The crop is usually 

 taken off in February and August or September, the whole of the above- 

 ground part of the plant being cut. The annual yield of dried leaves 

 varies from 15 to 19 cwt per acre. 



II. — ChemtcaIv Investigations. — According to Tommasi henna is 

 one of the few plants which have escaped the vigilance of plant chemists. 

 The aj^pended table gives the results of direct analyses and other addi- 

 tional determinations : 



Results of Henna Analyses. 



I/Caves BraiK-hcs 



Determinations — — 



— pel cent. per cent. 



Mjistiire at 100^-105" C 10.67 11. ic 



Fat (ether extract) 6 04 0.60 



Crude fibre 10.31 22.92 



Nitrogenous substances 1^.25 6.25 



Ash 8.64 3.28 



Non- nitrogenous extract (calculated) 50.89 55-55 



100.00 100.00 



Reducing sugars 14.04 6.14 



Ilydrolisable sugars .' 14.25 6.30 



I'entosans 7.17 11.72 



Tannin (cortex) 0.72 2.95 



Soluble substances (extract) 36.39 i3.7" 



Ash 3.80 — 



Substances soluble in acetone 18.73 — 



Substances soluble in absolute aleluinl . , . , 33.74 — 



