612 CONIFERiE. 



gent taste and a slightly acid reaction, and assume a purple hue on 

 addition of ferric chloride. When a solution of baryta is added to a 

 concentrated solution of larixin, the latter being in excess, a bulky 

 gelatinous precipitate falls; it is readily soluble in boiling water and is 

 deposited again on cooling. Stenhouse failed to obtain it either from 

 the bark of Pimus Abies L., or from that of P. silvestris L. 



Uses — Larch bark, chiefly in the form of tincture, has been pre- 

 scribed to check profuse expectoration in cases of chronic bronchitis; it 

 has also been found useful in arresting internal haemorrhage. 



TEREBINTHINA CANADENSIS. 



Balsamum Canadense; Canada Balsam, Canadian Turpentine; F. 

 Ter4henthine oil Baume de Canada; G, Canada-Balsam. 



Botanical Origin — Pinus halsamea L. (Abies balsamea Marshall), 

 the Balsam Fir or Balm of Gilead Fir, a handsome tree, 20 to 40 feet 

 high, with a trunk 6 to 12 inches in diameter, sometimes attaining still 

 larger dimensions, growing in profusion in the Northern and Western 

 United States of America, Nova Scotia and Canada, but not observed 

 beyond 62° N. lat. It resembles the Silver Fir of Europe {Pinus 

 Picea L.), but has the bracts short-pointed and the cones more acute at 

 each end. 



Canada balsam is also furnished by Pinus FraseH Pursh, the Small- 

 fruited or Double Balsam Fir, a tree found on the mountains of Penn- 

 sylvania, Virginia, and southward on the highest of the Alleghauies.^ 



Pinus canadensis L. {Abies canadensis Michx.), the Hemlock 

 Spruce or Perusse, a large tree abundant in the same countries as 

 P. balsamea, and extending throughout British America to Alaska, is 

 said to yield a similar turpentine, which however has not yet been 

 sufficiently examined. The Hemlock Spruce is of considerable import- 

 ance on account of the resin collected from its trunk, and the essential 

 oil distilled from its foliage, the latter operation being performed on a 

 large scale in Madison County, New York. The inner bark of the tree 

 is a valuable material for tanning. 



History — The French, in whose possession Canada remained until 

 the year 1763, were probably acquainted with Canada balsam long be- 

 fore this period. Yet no mention of it is found in Pomet's work, but 

 in 1759 it was at Strassburg a current article of the pharmacy.^ As to 

 England, Lewis, in his History of the Materia Medica published in 1761, 

 says that " an elegant balsam," obtained from the Canada Fir, is some- 

 times brought into Europe under the name of Balsam^um Canadense. 

 Canada balsam was first introduced into the London Pharmacopoeia in 

 1788. From the books of a London druggist, J. Gurney Bevan, we find 

 that its wholesale price in 1776 was 4s., in 1788, 5s. per lb. 



Description — Canada balsam is a transparent resin of honey-like 



^ Asa Gray, Botany of the Northern ^ Fliickiger, Pharm. Journ. vi. (1876). 



UnUed States, New York, 1866. 422. 1021. 



