530 THE PRINCIPLES OP EOTANV. 
Dr. Pereira says, “ Farriers sometimes employ it as a sub¬ 
stitute for cantharides for blistering horses, but cautious and 
well-informed veterinarians are opposed to its use. 5 ’ 
Such practitioners, then, as a rule should never trust the 
manufacture of a horse-blister out of his hands, and it would 
be well in making this useful application to procure sound 
Hies in the whole state, and powder them at home. 
We now describe the Ricinus communis , castor oil plant. 
This is an Asiatic-Indian plant, well known from very 
remote times for its medicinal qualities. It is cultivated in 
this country on account of its ornamental growth, its hand¬ 
some palmate leaves and bold method of growing giving it 
quite a handsome appearance. We always grow a few by 
placing the seeds in pots in a hot-bed in spring, and trans¬ 
planting them to the border in June. In warm summers it 
ripens its seeds, a few of which bruised have all the effects of 
castor oil. 
Castor oil, the product of the seeds, is too well known and 
too extensively used to require minute description in this 
place. It is considered both for man and the lower animals 
a safe purgative medicine, and when good, effects its purpose 
with but little irritation; but, on the contrary, if made by 
processes in which heat is employed, as fatty acids are 
engendered thereby, and hence “ cold-drawn castor oil ” is 
to be preferred, which is simply made by expression. It has, 
indeed, been much disputed whether certain acrid principles 
which castor oil sometimes possesses are really contained in 
the seeds, or are the result of decomposition, and this points 
to the importance of obtaining oil as pure as possible, though 
we are far from recommending those perfectly colourless oils 
that have been bleached in the sunshine, for though they 
appear so much more attractive as to cause some people to 
believe that it has but a minimum of nauseous flavour, ex¬ 
posure to sunshine certainly augments this objectionable 
quality. 
Croton tiglium is a tree of the order from the seeds of 
which the active medicine known as “ croton oil ” is derived, 
one drop of the oil being sufficient for a most active purga¬ 
tion. The plant itself is a native of the Indian Archipelago. 
It is used both as a purgative and a counter-irritant in 
numerous diseases of man and the lower animals. 
Croton elutheria yields the cascarilla bark, which is used 
medicinally as a tonic and aromatic bitter, and on account of 
its fragrant smell on being burnt it has been used for 
smoking mixed with tobacco* but we have no evidence of its 
effects in this state. 
