64 Dr. Nimmo on the 



portion was dissolved. A third quantity seemed to have little 

 eiFect; and even when it was aided by heat, though a slight 

 appearance of solution took place, the whole was precipitated 

 when it became cold ; and there was left an oily-looking sub- 

 stance, which appeared to be equal to somewhat more than 

 a third part of the original quantity of oil operated upon. On 

 tasting the alcoholic solution, I found it possessed of the cha- 

 racteristic acrimony of the oil : the undissolved portion had 

 none whatever. This solution of the active ingredient of the 

 croton oil I considered preferable, as c medicine, to the entire 

 oil, as obviating the following objections ; namely, the difference 

 of dose in consequence of the inequality in the thickness of the 

 lip of phials, the greater or less degree of viscidity in the oil at 

 different temperatures, and the difficulty of apportioning the 

 dose to difference of age or constitutional susceptibility to the 

 action of the ordinary purgatives. 



The rude analysis, practised above, shewed that the croton 

 oil was not a simple substance, but a binary compound, at 

 least ; one part consisting of the purgative principle, for in ad- 

 ministering the alcoholic solution in doses relative to the num- 

 ber of drops decomposed, the same effects were produced as 

 have been attributed to the entire oil ; the other part inert, for 

 having first tasted, and then taken, the whole of the residuary 

 oily substance, I found it entirely devoid of acrimony, slightly 

 rancid, and possessed of no power of moving the bowels. 



The supply of croton oil from London having been quickly 

 exhausted, and wishing to prosecute the investigation of its 

 properties by an extended trial, I was informed that a gentle- 

 man in town was possessed of a small quantity of the seeds, 

 with which he was so kind as to supply me ; and with the 

 view partly of obtaining a chemical analysis, but principally 

 to procure some of the oil, the quantity of which in the mar- 

 ket was reported to be nearly exhausted, the following series 

 of experiments upon them was instituted, which perhaps will 

 not be considered devoid of interest in a chemical point of view, 

 and of utility in the medical administration of this powerful 

 remedv. 



