102 Journal of the Asiatic Society of Bengal. |[April, 1905. 
11. The Colouring Principle of the flowers of Nyctanthes Arbor- 
trist’s—By HE. G. Hitt, B.A. 
The Nyctanthes Arbor-tristis, known in Urdu as “ Harsinghar,” 
is a large shrub of the order Oleacesze. The flowers are sessile in 
bracteate fascicles, they are pedunculate and are arranged in short 
terminal trichotomous cymes; the corolla: tube is orange, and the 
limb white. The flowers open at night and fall to the ground the 
following day. ‘They are then collected for use in dyeing. The 
plant grows most abundantly in the sub- Himalayan districts. 
For use in dyeing, the flowers are steeped or boiled in water 
and the solution strained off. It is a beautiful rich golden-yellow, 
and dyes cotton fabrics without a mordant. The effect is tran- 
sitory, the colour fading slowly. When used with alum or lime- 
juice the colour is brighter and less transitory, but the chief use 
of the dye is in combination with turmeric and safflower. It is 
seldom used with indigo. It is sometimes employed for colouring 
fancy leather-work. With safflower, turmeric, red ochre, myroba- 
lans and sulphate of iron it gives a fast maroon-brown, and with 
Butea frondosa and indigo and acidulated water, a fast grape 
een. 
No reference has been found to this flower in the chemical 
literature at my disposal, but in 1902, A. P. Sirkar made in my 
laboratory, a preliminary investigation into the colouring principle, 
which he considered existed in the flowers as a glucoside. He was 
unable to obtain this in a pure state, owing to its sparing 
solubility in most solvents, but he suggested C,;H.,O, for 
the colouring matter, although on boiling this with dilute hydro- 
chloric acid, he obtained a substance with a brighter colourand a 
higher percentage of carbon. He also considered that there were 
two methoxy groups present in the compound and at least one 
carbonyl group. 
The most noticeable feature of the colouring matter was the 
high percentage of hydrogen which was invariably obtained on 
combustion. 
The method of work was as follows :— 
Aqueous extract.—The flowers were extracted in cold water 
and the extract carefully filtered. The infusion was light -yellow 
in dilute, and dark-brown in concentrated solutions. It had a great 
attraction for flies. The infusion gave an acid reaction with litmus, 
and a yellow precipitate with basic lead acetate which became yellow 
onaddition of ammonia. With copper sulphate it gave a pale-yellow 
precipitate, which became green with ammonia. Stannous chloride 
gave a turbidity which disappeared on adding acetic acid. Ferric 
chloride gave a greenish-black colour which darkened on adding 
ammonia. Fehling’s solution was reduced, as were also gold chloride 
and ammoniacal silver nitrate. It gave no reaction with gelatin. 
When a few drops of the infusion were carefully added to a few 
cubic centimetres of concentrated sulphuric acid, an intense blue 
