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that the result of this has fairly proved that the poison of the seed, and so, by 

 a very proper inference, the poison of the plant generally, since I find an oily 

 substance throughout it, exists in this oil, if it is not the oil itself. It therefore 

 now only remains to be ascertained whether this oil is a single proximate 

 substance, or a mixture or compound of such, and if the latter, which is, or 

 which are, the active ones concerned in the production of these phenomena 

 I have described. Unfortunately I had not sufficient of the oil to allow me 

 to test this properly, but I am in hopes of having it by next autumn, 

 as I have been promised a large quantity of these seeds from Taranaki. 



The following are the characteristics of this oil, as ascertained up to the 

 present time. 



Somewhat viscid at common temperature, but flowing freely at a little 

 above this ; colour, pale-green ; reaction, acid ; taste, bland ; burns away 

 readily with much flame ; scarcely volatile without decomposition ; soluble in 

 ether, alcohol, chloroform, and strong acetic acid ; insoluble in hydrochloric 

 or nitric acid ; also insoluble in water ; does not dry when long exposed to 

 the air. 



When boiled with solutions of the caustic alkalies thei-e is much frothing, 

 but only a portion of the oil dissolves, even when the boiling is continued 

 for many hours ; the portion dissolved was found to be saponified. The whole 

 of the oil is, however, soluble in a cold alcoholic solution of potash, 

 without yielding a precipitate when admixed with water ; hence it is probable 

 that all the acid portion of the oil is really saponifiable, that which was 

 unsaponifiable, in the first instance, being a product of the metamorphosis of a 

 portion of the normal oil by the process employed. 



When the oil is heated to the decomposing point, a substance is given 

 off having the pungent odour of acrolein, a substance characteristic of the 

 the presence of glycerine, or oxide of lipyle the base of common fatty 

 bodies. 



Heated with caustic alkalies, either in the wet or the dry way, there are no 

 alkaline vapours evolved, but in the latter case an odorous oil forms, probably, 

 cenanthylic acid. 



From the reaction of this oil, here described, it evidently belongs to the 

 series of non-drying fixed oils ; in its solubility in alcohol or acetic acid, it 

 bears a remarkable resemblance to castor oil, the only other fixed oil, which 

 I find to be wholly soluble in acetic acid. Now castor oil, it will be 

 remembered, is a very peculiar oil : it does not contain any of the acids of 

 the common oils or fats, but in place of them, two very singular acids, quite 

 peculiar, I believe, to this variety of oil ; hence 1 conceive that the acid part 

 of this oil of Tutu to be also quite distinct from the ordinary fatty acids ; 

 to be in all probability, peculiar to it ; and to one or more of these acids I 

 should ascribe the poisonous effects of the oil. 



If further experiments should confirm the correctness of the views here 

 stated, this case will, I conceive, become invested with an interest beyond 

 that immediately under our notice ; since it will offer another instance in 

 which a non-nitrogenous oily principle, is proved to affect the system like a 

 neurotic poison ; this class of poisons being almost always alkaloids, or at 

 least nitrogenous substances. 



Now it will be remembered there are several poisonous plants in Europe, 

 which have, hitherto, refused to yield any pure poisonous principle to chemical 

 processes, but then these processes have been, as a general ride, I believe, 

 especially for the detection of alkaloids. With this case to point, therefore, it 

 does seem in the highest degree probable, that in some of these cases, at least, 

 the poisonous effects may be due to a non-nitrogenoiis oil, not yet isolated or 

 examined. In view of this I have recommended the subject for examination 



