1 74 Foreign Literature and Science. 



20. ActioJi of anhydrous sulphuric acid onjluor spar. — M. 

 Kuhlman, Professor of Chemistry at Lisle, has discovered 

 that fluor spar cannot be decomposed by anhydrous sulphu- 

 ric acid. This new fact is in favor of the opinion which 

 considers this body as a fluoruret of calcium. 



Ann. de Chim. et de Phys. Fev. 1827. 



21. Disinfection of Alcohol. — According to the experiments 

 of M. Accaric, confirmed by those of M. Chevallier, alcohol 

 which has been employed in the preservation of animal mat- 

 ters, is easily disinfected by adding to it, small quantities of 

 chloruret of lime, until the putrid odour has disappeared. It 

 is then to be distilled, and the product may serve for the pre- 

 servation of new substances, or for any other use in the arts. 



Ibid. 



22. Mosaic Gold, by Parker and Hamilton. — The pa- 

 tentees employ equal parts of copper and zinc, melted at the 

 lowest temperature at which copper will fuse ; and after hav- 

 ing stirred the mixture so as to produce a perfect combina- 

 tion, they add a fresh quantity of zinc in small portions, until 

 the alloy acquires the requisite color. If the temperature ot 

 the copper is too high, a portion of the zinc will be volatilized 

 and the result will be the mixture called strong solder, but 

 if the operation be conducted at a temperature as low as 

 possible, the alloy assumes a yellow color like brass, and then 

 by adding zinc in small portions the color changes to purple, 

 violet, and finally becomes perfectly white. This alloy may 

 be cast into ingots, or any other form, and when cold it pre- 

 sents the aspect of an alloy of fine gold and copper. But it 

 is difficult to preserve this color when remelted as the zinc 

 is easily volatilized if the heat be raised above the melting 

 point of copper. — Bull. Univ. Dec. 1826. 



23. Solution of Copal. — Many persons do not know that 

 the tedious process of dissolving copal in spirits of wine, be- 

 comes at once easy and expeditious by the addition of cam- 

 phor : thus, dissolve one ounce of camphor in a quart of alco- 

 hol ; put the solution into a suitable glass and add eight ounces 

 of copal in small fragments, place the mixture on heated 

 sand, whose temperature should be so regulated that the 

 bubbles which rise from the bottom may be counted as they 

 rise, and let it thus remain till the solution is complete. 



