168 



LIST OF ELEMENTARY SUBSTANCES. 



certained, for the reason that a single molecule is too 

 minute an object to be distinctly seen, or handled. 



The following table exhibits a list of the element- 

 ary molecules, arranged in alphabetical order, 

 with their relative weights as compared with mole- 

 cules of hydrogen, adopted as the unit standard 

 of comparison ; and hence these comparative 

 weights are denoted "chemical equivalents." 



TABLE OF ELEMENTARY SUBSTANCES AND OF THEIR 

 CHEMICAL EQUIVALENTS. 



