Origin and Production. Canada balsam, known in North America as balsam of fir and as balsam of Gilead, is used principally for mounting microscopic sections. It is obtained from Abies balsamea, Mill. (Pinus balsamea, L), which grows in British North America and in the northern and northwestern United States, but is collected principally in the Laurentine hills of the Province of Quebec. Some of the commercial balsam is said to be obtained from Abies Fraseri, Lindl., the double balsam fir of the Northern Alleghanies, also from Abies canadensis, Mchx. (Tsuga canadensis, Carr.), the hemlock spruce, Ger. Schierlingstanne1). These conifers secrete a clear balsam in special receptacles between sap wood and bark. The laborious collection of the balsam is conducted from the middle of July to the middle of August and is performed mostly by descendants of the Indians who camp in the forests during the summer. For tapping the honey-like balsam they use small iron cans provided with a pointed lip. With this lip they penetrate the bark of the pustules that are visible on the larger branches. The oleoresin flows slowly into the cans which are emptied daily and then stuck into a new reservoir. One man can collect little more than l/2 gal. or l1/2 kg. daily; with the aid of children, however, double this amount. After a campaign the tapped trees must be allowed to rest 1 to 2 years, otherwise the secretion of oleoresin ceases or is too small. The commercial center for Canada balsam is Quebec. The annual production is quoted variously but in all probability does not exceed 20,000 kg.2).
1) Observations made in the laboratory of Schimmel & Co.
2) The turpentine itself is dextrogyrate. Fluckiger observed aD + 9,5°, Schimmel & Co. +29° 20', hence the statement by Pereira (Pharmaceutical Journ. I. 5 (1845), 71), who says that the turpentine is lavogyrate, may be assumed as being erroneous.
3) Neues jahrb. f. Pharm. 31 (1869), 73; Jahresber. f. d. Pharm. 1869, 37.
4) Pharm. Review 23 (1905), 44.
Upon distillation, the balsam yields 16 to 24 p. c. of oil.
Properties. The odor of the oil is like that of turpentine oil; d15o0,862 to 0,865. Though the balsam is dextrogyrate the oil is laevogyrate3) aD - 264) to - 36°; n20o 1,4730 to 1,4765; it boils between 160 and 167°.
Composition, l-a-pinene is the principal constituent of the oil. Upon saturating the oil with hydrogen chloride, Fluckiger5) obtained a chlorhydrate C10H16Hc1, and Emmerich") prepared a nitrosochloride and from this pinene nitrolbenzylamine melting at 122°.
1) The last-named tree occurs in large forests along the lower St. Lawrence and in Nova Scotia, New Brunswick and westward to Minnesota.
2) Fred. Stearns, Americ. Journ. Pharm. 31 (1859), 29. - Wm. Saunders, Proceed. Americ. pharm. Ass. 25 (1877), 337; Pharmaceutical Journ. III. 8 (1878), 813.
3) Rabak, Pharm. Review 23 (1905), 48.
4) E. Dowzard, Chemist and Druggist 64 (1904), 439.
5) Fluckiger, Jahresber. f. Pharm. 1869, 37 and Pharmacographia p. 613. 6) Americ. Journ. Pharm. 67 (1895), 135.