CANADA BALSAM — a special type of the pitch received from Canadian, or balsam, firs (Abies balsamea), widely applied in histologic methods of a research. To. — transparent viscous liquid of yellowish color; during the drying hardens, keeping transparency. Index of refraction of light K. it is close to index of refraction of light of glass (n = 1,541 — 1,547) in this connection it is applied in the histologic equipment as Wednesday to drugs and also as agglutinant in the optical industry. To. let's dissolve in terpineol, a xylol, toluene, benzene and other organic solvents; in water it is insoluble. For preparation of working solution pieces dry To. fill in with one of solvents (it is possible in the thermostat) and after formation of homogeneous mass part with the same solvent to a consistence of liquid honey. Carefully dehydrated drug is placed on a slide plate, put a drop To. also I close cover glass. During the drying of solvent of glass are strongly stuck together, and drug between them can remain for years.
For the best safety of coloring it is recommended to use neutral To.; acid To. it is possible to neutralize by addition of powder of lithium carbonate, potash or baking soda. At absence To. it with success is replaced with fir balm from the Siberian fir (Abies sibirica) and a white-backed fir (Abies nephrolepis), damarlaky, the mystical masses (polyvinyl alcohol, polystyrene), etc.
See also Balms .
Bibliography: Merkulov, A. Kurs of the patologogistologichesky equipment, L., 1969; Romeys B. Mikroskopicheskaya of the technician, the lane with it., M., 1954.
Ya. Sh. Hesinonim