SECT. III. 93 



SECTION III. . 



ATOMIC THEORY, ANALYSIS AND SYNTHESIS OF MATTER, UTILITY OF 

 WASTE SUBSTANCES COAL-TAR COLOURS, ETC. 



THE chemical combination which, forms the infinite 

 variety of substances in the organic and inorganic 

 creation consists in an intimate union of their ultimate 

 atoms which produces substances differing from their 

 constituent parts in every respect except gravitation, the 

 sum of the weights of their constituent parts being in- 

 variably equal to the weight of the resulting" substance. 

 Thus the chemical union of oxygen and hydrogen forms 

 water, and the weight of the water so formed is exactly 

 equal to the sum of the weights of the two gases. 



All chemical changes whether of analysis or composi- 

 tion are subject to definite unalterable laws of weight, 

 measure and number ; nothing is by chance or casual, 

 the relative weights of the invisible atoms of matter, and 

 their combination in definite proportions reveal the laws 

 which prevailed in the primeval structure of created 

 things. By the wonderful discovery of these laws Dr. 

 Dalton has placed chemistry on a strictly numerical 

 basis. 



The chemical union of different kinds of atoms and 

 volumes of matter in the definite proportions of whole 

 numbers entirely changes their character and properties, 

 as for example the chemical combination of one atom, 

 of hydrogen and one atom of oxygen into water. The 

 condensation is often unexpected and wonderful; two 



