CHEMICAL MUSEUM. 



Some of the rarer or very expensive chemicals will be found in Case I. 

 in the Chemical Museum. These specimens are indicated by t- 

 Those specimens which are placed under shades are marked thus *. 



INORGANIC COMPOUNDS. 

 HYDROGEN. H. 



1. PEROXIDE. H 2 2 . (Hydroxyl, Hydric Dioxide.) 



a. Commercial specimen. 



Note. This is the ordinary aqueous solution : the old " oxygenated 

 water." 



NITROGEN. N. 



2. NITROSTL CHLORIDK. N Cl. (Ohloronitrous Gas. Monochloride 



of Nitrosyl.) 



a. Condensed gas, in a hermetically sealed glass tube. 



Note. This specimen was prepared by Dr. Tilden, whose researches 

 in connection with it are recorded in the Journ. Chem. Soc., 1874, p. 630. 



8. NITROUS ANHYDRIDE. N 2 3 . (Nitrogen Trioxide, Anhydrous Ni- 

 trous Acid. ) 

 a. Condensed gas, not quite pure. 



Note. This specimen was condensed by means of a freezing mixture. 

 Nitrous anhydride before exposure to the air condenses into a dark bine 

 liquid, but emits a red vapour which is soluble in the blue liquid. This 

 specimen having been very carefully prepared, is of a blue colour. 



4. NITRIC PEROXIDE. N0 2 . (Nitrogen Tetroxide, Hyponitric Acid, 



Nitroso-nitric Anhydride.) 



a. Condensed gas, in a hermetically sealed glass tube. 



Note. This specimen was condensed by means of a freezing mixture. 

 At 62 F. this specimen remains a brownish yellow liquid. Specimens 

 3 and 4 were presented by Messrs. Hopkin and Williams. 



CARBON. C. 



5. CRYSTALLINE. 



a. Models of the koh-i-noor and other diamonds. 



Note. This specimen will be found in the central cote, in which per- 

 feet crystal* and models of crystalline forms are contained. 



