SUCCINIC ACID. 75 



of water (corresponding with the above formula) it crystallises in 

 oblique rectangular prisms, which fuse at 180 and sublime at 250 

 in the form of needles or plates, containing only half an atom of 

 water, and fusing at 160. In other respects it has the common 

 characters of this group. 



Composition. According to the above formula it consists of : 



Carbon 4 atoms .... 40-678 



Hydrogen .... 2 .... 3-390 



Oxygen 3 .... 40-678 



Water 1 .... 15-254 



100-000 



The atomic weight of the anhydrous acid =625 '0 ; its saturating 

 capacity =16-000. Its rational formula=C 2 H 2 .C 2 O 3 .HO. 



Combinations. With alkalies this acid forms neutral and acid 

 salts, which are soluble and crystallisable ; with earths it forms 

 only neutral salts ; and with the oxides of the heavy metals it 

 forms neutral and basic salts, some of which are soluble and others 

 insoluble. 



Succinamide, H 2 N.C 4 H 2 O 2 , is formed by the action of ammonia 

 on succinate of oxide of ethyl ; it occurs in the form of gra- 

 nular crystals, insoluble in cold water ; like all the amides, it is 

 decomposed by alkalies or stronger acids into the corresponding 

 acid and ammonia. 



Bisuccinamide, or Succinimide, C 8 H 5 NO 4 , is formed on sub- 

 mitting succiiiamide to dry distillation, or on bringing dry ammo- 

 niacal gas in contact with anhydrous succinic acid ; it is a white, 

 crystallisable, fusible, soluble body, which, on being boiled with a 

 solution of potash, takes up 2 atoms of water, and becomes decom- 

 posed into ammonia and succinic acid (HN.C 8 H 4 O 4 + 2HO = 

 H 3 N+C 8 H 4 6 ). 



Preparation. This acid was, as its name implies, originally 

 obtained from the dry distillation of amber. It was discovered in 

 the sixteenth century. It has since been found to exist pre-formed 

 in certain kinds of turpentine and in certain plants. It, however, 

 occurs much more frequently as a product of the decomposition of 

 fats, as wax, stearic acid, spermaceti, margaric acid, &c., and in 

 various kinds of fermentation : thus, for instance, malate of lime, 

 in contact with nitrogenous bodies, becomes gradually converted 

 into succinate of lime (CaO.C 4 H 2 O 4 -O=CaO.C 4 H 2 O 3 ). 



According to C. Schmidt,* succinic acid is found in greater or 



* Handworterbuch der Cheinie, von Liebig^ Wohler, u, Poggendorff. Bd. 3, S. 224. 



