1843] WRITINGS OF JOSEPH HENRY. 211 



TRANSPARENT SOLIDS. (CONTINUED.) 

 Permeable, 



Borax, Alum, 



Citric acid, Horn (pellucid), 



Rochelle salt, Wax, do. 

 Common salt. 



Imperfectly permeable. 



Tourmaline, Tartaric acid. 



Mica, Hyposulphate of soda, 



Flint glass, Copal, 



Crown glass, Camphor. 



Saltpetre, 



TRANSPARENT LIQUIDS. 

 Permeable. 



Water, Sulphate of magnesia, 



Solution of alum, Nitrate of ammonia, 



Solution of ammonia, And all weak solutions. 



Imperfectly permeable. 



Muriatic acid, Arsenious acid. 



Sulphuric acid, Ammonia, 



Nitric acid. Spirits of turpentine. 



Phosphoric acid. Alcohol, 



Sulphate of zinc. Ether, 



Sulphate of lead, Oil of aniseed. 



Acetate of zinc, Acetate of lead. 



