CORTEX LARICIS. CTl 



CORTEX LARICIS. 



Larch Bark. 



Botanical Origin — Piniis Larix L. — see p. GOO. 

 History 



y — The bark of the larch has long been knowTi to possow 

 iwuiiiiguiiu properties; hence it has been used in tannini:?, Gcrarile,' who 

 Avrote near the close of the 16th century, likened it to that of tlic pine, 

 which he described to be of a binding nature; but there is no eviacn 



astrinofcnt 



officinal 



i^uai it vv<i» nil uiiicixiai arug. 



About the year 1858 larch bark was recommended by Dr. Frizell <»f 

 Dublin, and afterwards by other physicians, as a stimulating astrin-tnt 

 and expectorant. In consequence of the favourable effects which havr 



AdditiO'^ tothcFhar- 



>/ 



Description— The bark that we have seen is in flattish pieces or 

 large quills, externally reddish-brown. In those taken from older wood 

 there is a large amount of an exfoliating corky coat, displaying as it is 

 removed bright rosy tints, while the liber is of a different texture, s hghtly 



fibrous and w^hitish. 

 or pale yellow. T 



piidcish 



ng 



ked astringent 



taste. For medicinal use the inner bark is to be preferred. 



Microscopic Structure— A transverse section cxlnbit^ rcsin-duct , 

 but far less numerous than in the bark of many alhed tiv.i. ine 

 medullary rays are not very distinct. Throughout the ""'''^' ^T «r. 

 the bark large isolated thick-walled cells of very irrcndar shape art 



scattered. 



tannin 



mical Com 

 who finds i 



examine 



The same 



ist ''also discovere^d^ in "larch bark an ^'^f'^'l^'^^'^^on 

 suDstance called Lariayln or Larvdnw Acid, which has ^ ,e comp<«mo 

 C"H-0^ It may be obtained by digesting the bark m ^va^^^^^" ^; 

 and evaporating the infusion to a syrupy consistence. From tmy 



bini turther cautious heating inarewit, ^i- — ^ k j^,fa^ 



during which operation sonfe of it cp-talhz^s on tjie^^^^^ 

 of the receiver, the remainder being dissolved 'if''^^^^^ Vh. 

 From the latter it may be obtained in crystal ^T ^^^f^f^^j, !,„,; 

 substance forms colourless crystals, sometimes as »^^^^ ^^j^.^ j^l„,„t - 

 It volatilizes even at 93° C, and melts at ^-^^ • ,'^\. .^1,-, jp boilir- 



parts of water for solution at 15^ C, but "f ^.^/f^^^^ .^.^Hn-ly ^-lubk, 

 water or in alcohol. From ether, in which it is out i . «/|^ j^^t,i„. 

 it separates in brilliant crystals. The solutions ha^ . a 



pentine and another of common turpentine , ,„/^ ,«fifi 



be spread on two sheets of paper it ■« ill be ^^%JiyZ:Jinas of the Royal Society, xi. 



found after the lapse of some weeks that ,.J^!^'^nr ^ „ ... 



the former cannot be touched without ad- ^T Phil Trans., vol. 152 (1862) 5.3.-^^ e 



rixin instead 



iave Serome\ dri;rW v:i;:ish ^Sf^S: crc^rr^nre of D;:Stenhou.e 



