AlilES — SPRCCE. 257 



viscid, snmowhat opfilesront liquid, of an fip;rcral>le odor and a pinigent, 

 bitterisli taste. ]'!xiK)se(l to tlio air for a k'n<4lli of tiiiio it c«ncrt'tt'8, and 

 forms a tou^li mass wliicli is brittle when cold. It consists of volatile oil 

 and rosin. The former is sei)aratcd by distillation, and is the spirit of 

 turpentine of commerce, while the latter is the non-volatile residue, com- 

 mercially known as rosin. Tar is an cniiiyreumatic oleorcsin of very com- 

 plex composition, containing acetic acid, methylic alcohol, creasote, car- 

 bolic acid, etc. 



I'rcparnlioiifi. — Of turpentine : Oleum terebinthina' — oil of turpentine, 

 resina — resin. Preparations of oil of turpentine : Linamentum canthan- 

 dis — cantharides liniment ; linamentum terebinthinic— turpentine lini- 

 ment. Preparations of resin : Ceratum resinm — resin cerate ; emplastrum 

 r(!sin!r — rosin plaster. Preparations of tar : Sj-rupus picis liquiihe — synip 

 of tar ; unguentum picis liquicUe — tar ointment.— ('////crZ Stales riianua- 

 copci'ia. 



Medical Properties and Uses. — Crude turi^ontine is seldom or never 

 used internally at the present daj-^ ; since its virtues are believed to reside 

 chiefly in its essential oil, this is almost universally employed instead. Oil 

 of turpentine is stimulant, diuretic, anthelmintic, and in lai-ge doses, catliar- 

 tic ; externally it is rubefacient and mildly vesicant. In hduvU, frequently 

 repeated doses it stimulates the kidneys, augments the secretion of ui-ine, 

 and occasionally produces stranguiy and luematuria. In large doses it 

 produces \ertigo, nausea, and often brisk catharsis. It is used in a great 

 variety of cases. Like other terebinthinate medicines it is often employed 

 in the later stages of gonorrho'a, and in other catan-hal ailections. In 

 typhoHl fever, and in other iili'ections whore tynqutnites is a jn-ominent and 

 disti'cssing symptom, it often aftbrdi^ great relief ; and, indeed, in low ty- 

 phoid conditions generally its employment is commonly very satisfactory. 

 Its controlling influence in passive hemorrhages has also long been recog- 

 nized and made use of. As a vermifuge it often enters into tho conqwsi- 

 tion of draughts for the expulsion of taniia. Externally, alo' or in com- 

 bination, it is largely employed as a rubefacient. 



Resin is employed as an ingredient of plasters and cerates, to which it 

 gives consistence and adhesiveness, without adding sensibly to their ac- 

 tivity. 



The medicinal properties of tar are similar to those of turpentine, 

 modified, however, to some extent by the puiely empyreumatic bodies 

 which it contains. It is used internally and by inhalation in chronic ca- 

 tai-rhal ati'ections, and externally in a variety of cutaneous diseases. 



ABIES.— SmucE. 



Charnrtcr of the Genus. — Sterile catkins scattered or clustered in the 

 axils of the leaves of the preceding year ; fertile catkins lateral or terminal 

 on the branches of the preceding year ; both appearing in spring, the cones 



