60 Appendix. 



of the aldehydes. In the following list, each dash prefixed indi- 

 cates the displacement of one atom of hydrogen from benzene ', C 6 H 6 , 

 to the residue of which the additions are made. Thus, benzoic 



acid is C 6 H 5 C | QH etc., (the H of OH in acids being re- 

 placed by metals, forming salts). 



Acid. Aldehyde. Alcohol. 



Benzoic C { TT C { c ( ** 



(OH 



OH OH OH 



f 

 F 

 OH 



Salicylic \ C { w _ _ r f O fl 



Cinnamic 

 (Phenyl 



ic ) C | O ) 1 H 



[(C 3 H 3 y [n 



-acrylic) ) ( (C 3 H 3 ) W JO O (C.H,)'" O 



Cuminic ) ( fC 3 H 7 )' (C 8 H.)' (C.H.)' 



r! N 



(Phenyl-propylic) ) ( ' \ OH " " { H C ] H 



OH 



Anisic 



isic -j 



Benzoic acid 'is accompanied in the balsams, ( 13 ) and often 

 complemented by cinnamic acid. It is formed from its aldehyde, 

 bitter almond oil, by exposure of the latter to air. It is now 

 manufactured from the naphthalin of coal tar (the double mole- 

 cule benzene before described), by the process mentioned farther 

 on. Benzoic aldehyde is hardly an educt ; being a product, along 



(13) Styrax benzoin, Myrospermum toluiferum, Myrospermum perui- 

 ferum, Eunonymous Europceus. 



