Chap. 7.
Empyreumatic Oils.
ermoft: fuffer this to run out;then clofe the flem again, and af-terwards feparate the acid liquorfrom the lighter oil in the famemanner. They are more perfeftlyfeparated, by pouring them into ahollow cone of filtering paper, moi-itened with water, and placed in afunnel: the acid liquor paiTesthrough, and the oil remains onthe paper.
The oils obtained by this treat-'ment from different woods andplants, are nearly of the fame qua-lities : they have all a very dif-agreeable acrid tafte, and a burntftinking fmell; without any thingof the peculiar flavour, tafte, or vir-tues of the fubjedt which affordedthem. The prefent praftice rarelyemploys thofe oils any other wifethan for external purpofes, as theclean fing of foul bones, for thetooth-ach, againft fome kinds ofcutaneous eruptions, old pains andaches, and the like; and for thefenot very often.
OLEUM LATERITIUM.
Oil of bricks.
Land.
Keat bricks red hot, and quenchthem in oil olive, till they havefoaked up all the oil: then breakthem into pieces fmall enough tobe conveniently put into a re-tort ; and diftil with a fand-heatgradually increafed : an oil willarife, together with a fpirit,which is to be feparated from itas in the foregoing procefs.
Th is preparation has had a placem moll difpenfatories, under thepompous names of oleum philofo-phorum, fanttum, divinum, bene-<H£lum, and others, as improper asthat under which it ftands above.It is really oil olive, renderedftrongly empyreuraatic by heat:the fpirit, fo called, is no more than
419
phlegm, or water, tainted With theburnt flavour of the oil. It hasbeen celebrated for fundry externalpurpofes, particularly againlt goutyand rheumatic pains, deafneis andtingling of the ears, See. and fome-times likewife given inwardly.But common pra£lice feems tohave now entirely rejefled thisloathfome remedy; and the col-lege of Edinburgh have expungedit from their book.
OLEUM PETROLEl BARBA-DENS1S.
Oil of Barbadoes tar.
Lond.
Diftil Barbadoes tar with a fand-heat ; an oil will arife, toge-ther with a fpirit, which is tobe feparated from it.
Dr. Pembertoh obferves, thatthis oil will be more or lefs thin,according to the continuanceof thediftillation ; that the tar will atlaft be reduced to a black coal,and then the oil will be pretty deepin colour, though perfeftly fluid :that this oil has a property fimilarto that of the tin&ure of nephriticwood in water, appearing bluewhen looked upon, but of anorange colour when held betwixtthe eye and the light. By longkeeping, I have obferved it to lofethis property. It is fomewhat lefsdifagreeable than the foregoingoils, though very acrid and ftimu-lating.
OLEUM TEREBINTHINL©^ETHEREUM; et empvreu-maticum five BALSAMUM.
The ethereal oil of turpentine, andthe empyrcumatic oil or balfam.
Lond.
Diftil the effential oil of turpentinein a retart, with a very gentlefire, until what remains has ac-E e 2 quired