DR. JOHN STENHOUSE ON VEGETABLE PRODUCTS FROM INDIA. 
155 
The Ptychotis oil, according to my experiments, contains a hydrocarbon boiling at 
172 °, and forming a liquid hydrochloric acid compound, and a crystallizable sub- 
stance melting at 44° C., and boiling at about 222° C. The principal angles are stated 
by Professor Miller to be — 
o > 
“ Crystallized on cooling . . . rr' =98 38 
Indian crystals me =98 40 
Indian crystals mm' = 8I 18 
Indian crystals m'c =81 20.” 
Two properties, however, I observed different from those given by Lallemand, viz. 
that the stearopten oHhe Ptychotis is precipitated (in aliquid state) from its alcoholic 
solutions by water, and that potash does not dissolve it, but merely causes it to 
assume the liquid state. 
From the results of these experiments, therefore, I think we may confidently infer 
that the stearopten of the Ptychotis oil, and the crystallizable oxygenated portion of 
oil of thyme, examined by Lallemand, if not identical, as I apprehend they are, are 
certainly extremely similar bodies. 
Gum of the Gardenia lucida, Roxb. {the Decamalee Gum of Scinde). 
The specimen of this gum on which I operated was evidently very old. It formed 
a hard, dry mass, of a dark brown colour, with numerous patches of greenish-yellow 
matter disseminated through it. It had but a faint odour, unless freshly fractured or 
gently heated, when it smelt like the urine of the oat. A comparatively recent spe- 
cimen of this gum, which I saw in the hands of the late Dr. Stocks, had nearly the 
consistence of candied honey, and an exceedingly offensive odour. Dr, Stocks 
informed me that the recent gum was employed as a dressing for wounds, as it kept 
off the flies. 
The resin was digested in strong spirits of wine till a saturated solution was 
obtained. This, on cooling, immediately deposited some yellow, amorphous flocks. 
These were separated by filtration, and the clear liquid slowly evaporated in vacuo. 
On standing a few days, it deposited slender golden-yellow crystals, about half an 
inch in length. The crystals had considerable lustre, and were very brittle. To this 
crystalline substance I propose giving the provisional name of Gardenine. 
Gardenine is nearly insoluble both in cold and hot water. It dissolves pretty 
readily in alcohol, but much less easily in ether, yielding bright yellow solutions, out 
of which it crystallizes on cooling. Alkalies, such as ammonia, do not appear to 
increase its solubility. It is slightly soluble in hot hydrochloric acid. Strong oil of 
vitriol dissolves gardenine in the cold with the production of a beautiful dark red 
colour. On adding water to this solution the gardenine is precipitated apparently 
unchanged. Its alcoholic solutions give no precipitates with ammonio-nitrate of 
silver, or with basic acetate of lead. When gardenine is digested with concentrated 
