RICINUS COMMUNIS. 
3 
from the bruised seeds by means of a hand-press ; but this oil is 
thought more acrimonious than what is prepared by coction."* Dr. 
Brown, of Jamaica, is also of thi^ opinion, preferring the oil obtained 
by coction to that by expression, and attributes its greater mildness 
to the action of the fire. This acrimony, however, appears from 
later experiments to be owing to the membranes which invest the 
kernel. In this country, the cold-drawn oil is always preferred, for 
the reasons we have already stated, and bears a much higher price. 
The oil obtained is equal to one-fourth of the weight of the seeds 
employed. It is often adulterated with olive oil, linseed oil, and 
poppy oil : the adulteration maybe detected by adding an equal 
quantity of alcohol, sp. gr. 820, to any given quantity of the oil ; if 
it be pure an uniform solution will take place, which will not be the 
case should it be adulterated ; a weaker spirit, with the addition of 
camphor, may likewise be employed as a test. 
Sensible Properties. Good expressed castor oil is nearly 
inodorous and tasteless, but even the best leaves a slight sensation of 
acrimony in the throat after it is swallowed ; it is thick, viscid, 
transparent, and colourless, or of a very pale straw colour. The oil 
obtained by coction is of a deeper hue ; and both kinds, when they 
become rancid, thicken, deepen in colour to a reddish brown, and 
acquire a hot, nauseous taste. It has all the chemical characters of 
the other expressed oils, except that it is heavier, and is very soluble 
in alcohol and in sulphuric ether.f 
Orfila classes the fruit of the Palma Christi among the acrid 
vegetable poisons of his Toxicology : the seeds, he says, " produce 
a local irritation, and act upon the nervous system after being 
absorbed." His experiments, however, are by no means sufficient 
to establish this fact, for in all of them, except one, the cesophagas 
of the dogs which were the subjects of the experiments was tied, 
and the animals died within from twenty-four to forty-eight hours 
after the introduction of the seeds into the stomach. In the first 
experiment, where a small dog was made to swallow thirty grains of 
these seeds, Orfila says, that " at the end of twenty minutes he 
Tomited without any eftbrt some white matter, stringy and Hquid, iu 
which the ingested fruit was observed ; at nine, he passed a stool, 
partly Uquid, partly solid, and experienced no further inconvenience ; 
in the course of the day he fed heartily." Now we would be inclined 
* Long's Jamaica, p. 713. 
f Thoiasou's Materia Medica, 
