Secondary Laws. 99 



Section 3. Chemical Attractioji : 



Definition : Chemical attraction is the force which 

 causes different kinds of matter to unite and 

 transform into a new substance. 

 Chemical attraction, like gravity and cohesion, is 

 merely a name for a cause unknown. Manifested, 

 however, in diametrically opposite ways, and con- 

 sequently classed into two sections — Chemical Com- 

 bination, and Chemical Decomposition or Repulsion 

 — an investigation of these phenomena separately 

 shall probably reveal the information required. 



1. — Chemical Combination : 



Definition : Chemical combination is reciprocal 

 attj'action between two or more specific substances 

 resulting in the formation of a totally different 

 product. 

 Chemical combination is usually defined in text- 

 books as "the operation of chemical attraction,". but 

 as this " operation " is itself unexplained, we need 

 hardly say the definition lacks lucidity. The chief 

 facts of chemical combination are : — ■ 



(1) It is an atomic or molecular process; that is 

 atoms and molecules must be in a suitable free con- 

 dition before they can effect combination. 



(2) " Only bodies of different kinds rush together 

 and unite after this fashion." 



(3) The products of chemical combination, as car- 

 bonates, sulphates, or silicates, are bodies manifesting 

 cohesion. 



