24 FORMS OF MATTER. 



course, possess a motion made up of a 

 combination and modification of the special 

 motions of the two atoms a tertium quid 

 motion, so to say. Chemists also believe 

 that four of the atoms combined to form 

 a molecule of phosphorus, which of course 

 must also possess quadruple activities ; and 

 that six atoms combined to form a molecule 

 of sulphur, which in like manner must 

 possess six-fold activities ; and so on for 

 the formation of the other elementary 

 substances, each having its own special 

 activities, its own attractions and repul- 

 sions, its own polarities. 



Hence arose the mutual attractions, 

 repulsions, and elective affinities, sometimes 

 very strong, amongst the chemical elements, 

 that caused one element to attract and 

 unite with some elements and repel others, 

 thus forming the various compound bodies 

 known to chemists ; for instance, molecules 

 of hydrogen united with molecules of 

 oxygen and formed water ; molecules of 

 oxygen united with molecules of potas- 

 sium and made potassium oxide, and 

 with molecules of ferrum made ferrous 

 oxide ; single molecules of oxygen united 

 with single molecules of carbon and made 

 carbon monoxide; single molecules of 



