480 MATERIA MEDICA 



Essence of Mustard appears to be composed of mustard, 

 camphor, oil of rosemary, and oil of turpentine, which form a 

 good stimulatino; embrocation. See Embrocation. 



ESSENTIAL OILS. The smell, taste, and other qualities 

 of vegetables frequently reside in a volatile oil, particularly in 

 those" vegetables or certain parts of vegetables, that have a 

 strong odour and taste ; as mint, penny-royal, peppermint, la- 

 vender, caraway-seeds, anise-seeds, juniper-berries, lemon-peel, 

 sandal-wood, &c. Tliis oil, being volatile, may be extracted, 

 and procured in a separate state, by distillation ; and, as it often 

 contains the useful qualities of the substance it was obtained 

 from, is termed an essential oil. See ESSENCE. 



ETHER, SULPHURIC— ^^/ifr Sulphuriciis. This is the 

 most volatile liquid we are acquainted with, and evaporates 

 readily in the common temperature of the atmosphere ; it must 

 be given, therefore, with great expedition, or a considerable 

 part of the dose will be lost by evaporation. Sulphuric ether is 

 a powerful stimulant, and must be given Avith caution. I have 

 known a dose of two ounces destroy a horse, but it was given in 

 a case that was supposed to be the flatulent or spasmodic colic, 

 but which was probably inflammation of the bowels. [It is a 

 valuable medicine for flatulent colic, in doses from four drachms 

 to an ounce, combined with tincture of opium. Since the pre- 

 vious edition of this work was published, the vapour of sulphuric 

 ether has been employed for the purpose of preventing the sen- 

 sation of pain, and thus facilitating the performance of various 

 operations. It has, however, now given place to chloroform, the 

 effects of which, though similar, are found superior. The writer 

 has operated successfully on many occasions. — Ed.] 



ETHIOPS MINERAL. — i/^fZrorr/^n Sulphuretum Ni- 

 grum. Black sulphuret of mercury. A preparation made by 

 rubbing equal parts of quicksilver and flour of sulphur together, 

 imtil the mixtui'e becomes black, and the quicksilver invisible. 



Ethiops Mineral, though generally considered as a medicine 

 of little power or nearly inert, is, I am inclined to believe, pos- 

 sessed of considerable virtue, and will be found, probably, as 

 good a mercurial as can be employed, in all cases where it is ne- 

 cessary to introduce mercury into the circulation, as in farcy, 

 glanders, obstinate cases of mange, &c. It should be given in a 

 dose of two or three drachms in the horse's corn, once or twice a 

 day, until an offensive smell is perceived in the animal's breath, or 

 he is found to stale more than usual ; for these symptoms indicate 

 that the mercury has got into the circulation. The disorder for 

 which it is given may, at this period, be expected to yield to the 

 mercurial influence, and may not require a farther continuance 

 of the medicine. I would advise a trial being made of Ethiops 

 mineral in the early stage of glanders. M. Volpi, one of the 



