1. APPARATUS AND SPECIMENS ILLUSTRATING 

 THE APPLICATION OF CHEMISTRY TO 

 RESEARCH. 



A. APPARATUS INTENDED TO BE USED IN LABORATORIES AND 

 LECTURE ROOMS. 



1. Series of J-inch cardboard cubes, with different 

 colour for each chemical element on which its symbol, 

 atomic value, and combining weight are marked, illustrat- 

 ing the laws of chemical combination and the binary 

 theory of Salts. 



1876. Lent by Rev. Nicholas Brady, M.A. 



Only a comparatively small number are sent, as they will 



sufficiently show their method of use; thus 



H 



H 







represents the molecule of water, the dyad oxygen requiring 

 two monads to satisfy it, the molecular weight of the com- 

 pound being 1 + 1 + 16 = 18. 



2. Case containing five stands and a collection of spheres 

 made to demonstrate the structure of chemical com- 

 binations according to the theories of A. W. Hofmann. 



B. 271. 1877. Made by Manuel Gonzalez, Madrid. 



3. Large copper gas holder, of bright metal. 



Made by Warmbrunn, Quilitz, fy Co., Berlin. 

 E. 139. -1877. 



The apparatus consists of a cylindrical reservoir of copper, 

 fitted with an entrance tube for water, an exit tube for the gas 

 with a long tapering nozzle, and a glass water gauge. There is 

 no top-water reservoir. 



4. Large copper gas holder, bronzed, with top-water 

 reservoir. 



Made by Warmbrunn, Quilitz, fy Co., Berlin. 

 E. 140. 1877. 

 Similar to the above, but fitted with a top- water reservoir. 



5. Gasometer, consisting of tub with iron vessel to be 

 raised and lowered within it by means of pulleys. 



From the Pedagogical Museum, St. Petersburg. 

 E. 744. 1877. 



