214 CEMB3NTS ANM) VARNISHES. 



The turpentine distributes itself evenly along the side of the 

 cover, and hardens immediately, so that the slide may be 

 cleaned as soon as the four sides are finished. It is claimed 

 for this cement that it is perfectly secure, very handy, and 

 never runs in. Parker saw this cement, or a similar one 

 known as Venedischer Damarlack, exclusively used for gly- 

 cerin mounts in the Pathological Laboratory at Vienna. 



This is an extremely valuable method. It is very rapid and 

 very safe. The cement sets hard in a few seconds. 



421. Colophonium and Wax (KRONIG, Arch. f. mik. Anat., 

 1886, p. 657; Journ. Roy. Mic. 8oc., 1887, p. 344). Seven 

 to nine parts of colophonium are added piecemeal to two 

 parts of melted wax, the whole filtered and left to cool. For 

 use, the mass is melted by placing the containing vessel in 

 hot water. The cement is not attacked by water, glycerin, 

 or caustic potash. 



422. Amber Varnish. As above mentioned, BEHRENS finds 

 this cement to possess an extreme tenacity. He does not 

 give the composition of his varnish, which was procured from 

 E. Pfannenschmidt at Dantzic. The following is from COOLEY'S 

 Cyclopaedia, Art. "Varnish " : 



" Take of amber (clear and pale) 6 Ibs., fuse it ; add of hot 

 clarified linseed oil 2 gallons, boil it until it " strings" well, 

 then let it cool a little and add of oil of turpentine 4 gallons 

 or q. s. v ' 



Other receipts, 1. c. 



423. Amber and Copal Varnish (HEYDENEEICH, Zeit. f. wiss. 

 Mik., 1885, p. 338). An extremely complicated mode of 

 preparation. The varnish may be obtained from Ludwig 

 Marx, at 110, Moskowskaja Sastawa, St. Petersburg, or 79, 

 Graden, Vienna, or 1, Romerthal, Mayence. 



424. Shellac Varnish (BEALE, p. 28). Shellac should be 

 broken into small pieces, placed in a bottle with spirit of 

 wine, and frequently shaken until a thick solution is obtained. 

 The Micro. Dictionary says that the addition of 20 drops of 

 castor oil to the ounce is an improvement. 



Untrustworthy, but useful for protecting balsam mounts 

 from the action of oil of cedar. 



For a method of preparing chemically pure shellac (a some- 



