LECTURE VIII.] HISTORY OF CHEMISTRY. 147 



is distinguished by very marked advantages over the radical 

 theory, which, owing to the very definite form that had been 

 given to the radical, could only be of service in certain direc- 

 tions, while it wholly overlooked various relationships. 



I think it may be advantageous to show, by means of a few 

 examples, the mode in which Laurent applied his theories, and 

 also what his formulae were for different compounds. In doing 

 this I shall choose familiar groups of substances. 

 Nucleus, Etherene C 4 H 8 [C= i2] 46 

 Etherene Hydrochlorate C 4 H 8 + H 2 C1 2 



Chloretherase C 4 H 6 C1 2 



Chloretherase Hydrochlorate C 4 H 6 C1 2 + H 2 C1 2 



Chloretherese - C^C^ (then unknown) 



Chloretherese Hydrochlorate C 4 H,C1 4 + H 2 C1 2 



Chloretherise C 4 H 2 C1 6 (then unknown) 



Chloretherise Hydrochlorate C 4 H 2 C1 6 + H 2 C1 2 4T 



Chloretherose C 4 C1 8 



Etherose Chloride C 4 C1 8 + C1 4 



Chloral C 4 C1 6 O + H 2 O 



Bromal C 4 Br 6 O + H 2 O 



Chloracetic Acid (then unknown) C 4 H 2 C1 4 O + O 2 



Nucleus, Methylene C 2 H 4 

 Chloroform - C 2 C1 4 + H 2 C1 2 



Bromoform C 2 Br 4 -f H 2 Br 2 



Cyanogen C 2 Az 2 



Hydrocyanic Acid - C 2 Az 2 + H 2 



Cyanic Acid C 2 Az 2 + O 4S 



Nucleus C 14 H 14 



Bitter Almond Oil - C 14 H 10 O 2 + H 2 



Benzoic Acid - C 14 H 10 O 2 + O 



Hydrobenzamide C 14 H IO Az 4 / 3 4- H 2 49 



46 Ann. Chim. [2] 63, 388 ; Annalen, 22, 303. 47 The principle of 

 the nomenclature employed originated with Dumas (Ann. Chim. [2] 57, 

 305). Laurent almost always used this nomenclature. 48 The symbol 

 Az (Azote) was written for the nitrogen atom in France at that time (as it 

 still frequently is). I have used it here for a reason that will be perceived 

 further on, 49 Ann. Chim. [2] 62, 23. 



