Part II.
Materia Medica.
215
transparent, and have a more agreeable flavour than the otherkinds. The common turpentine, as being the most offensive,is rarely given internally ; its principal use is in plasters andointments among farriers, and for the distillation of the essen-tial oil.
Medical use. —Taken internally, they are active stimulants,open the bowels, and increase the secretion of urine, to whichthey give the smell of violets, even though applied only exter-nally. In all cases accompanied with inflammation, they oughtto be abstained from, as this symptom is increased, and notunfrequently occasioned by them. They are principally re-commended in gleets, fluor albus, and the like. Their doseis from a scruple to a drachm and a half. They are most com-modiously taken in the form of a bolus, or blended with wa-tery liquors, by the mediation of the yolk of an egg, or muci-lage. They also may be given in the form of electuary, mix-ed with twice their weight of honey, and in the dose of adrachm of the compound twice or thrice a-day ; or of clyster,half an ounce being well triturated with the yolk of an egg,and mixed with half a pound of gruel, or decoction of chamo-mile.
By distillation turpentines are analysed into two products,a solid resin and a volatile oil.
Oil of Turpentine is officinal in the Edinburgh and LondonPharmacopoeias ; by the Dublin college directions are givenfor its preparation. At Queensferry, in this neighbourhood,there is a considerable turpentine work : the turpentine usedcomes from America, and therefore it is not a product of anyof the officinal species of pine.
Oil of turpentine is lighter than water, transparent, limpid,and volatile. It has a hot pungent taste, and a penetratingsmell ; is highly inflammable, and possesses all the other pro-perties of essential oils.
It is remarkably difficult of solution in alcohol, althoughturpentine itself dissolves easily. One part of the volatile oilis indeed apparently taken up by seven of alcohol ; but onstanding, the greatest part of the oil falls to the bottom, amuch larger quantity of alcohol being necessary to retain itin solution.
Med. use. —As a medicine, it is highly stimulating and pe-netrating. Internally it acts as a diuretic or sudorific in verysmall doses. It has also been given in large doses, mixedwith honey, principally in those modifications of chronic rheu-matism which are styled sciatica and lumbago. But it has notbeen often successful, and sometimes has had the effect of in-ducing bloody urine.
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