222 Journal of Agricultural Research voi. xxn,No.4 



solution was drawn ofif through a tubulature at the bottom of the jar. 

 It was not until succinic acid instead of one of the usual fruit acids was 

 isolated from this solution that suspicion arose as to the possibility of 

 any fermentation, other than an autolytic one, having occurred, and it 

 was then too late to examine the solutions for microorganisms. It can 

 only be stated that there was no evidence that such were present. The 

 high acidity would have prevented bacterial action, and the perfectly 

 clear solution, saturated with chloroform and toluol, showed no evidence 

 of the presence of yeasts. 



The infusion was neutralized by stirring with calcium carbonate. 

 During this process rapid darkening took place, with the formation, 

 presumably, of the same brown oxidation product that forms when a 

 cut surface of apple is exposed to the air. A dark precipitate separated, 

 which was not a salt of one of the fruit acids. It was filtered off. From 

 the filtrate it was possible to get relatively pure succinic acid by acidi- 

 fying with hydrochloric acid and shaking with ether, but the more econom- 

 ical and easy procedure, by which a larger yield was obtained, is 

 described below. 



The neutralized filtrate was evaporated to a small volume and pre- 

 cipitated with several volumes of ethyl alcohol. An impure calcium 

 salt separated as a sticky, molasses-like mass. It was dissolved in dilute 

 hydrochloric acid, and the solution was concentrated until the succinic 

 acid crystallized out. It was purified by crystallization from lo per 

 cent nitric acid, and finally by repeated recrystallization from water. 



The pure acid thus obtained agreed in all properties with succinic acid. 

 It melted at 184° to 185° C. (Rosenthaler (13) ^ gives 185° C). The 

 reaction mixture obtained by heating with concentrated sulphuric acid, 

 when diluted, boiled, and neutralized with ammonia, gave a red solution 

 with a strong green fluorescence, a characteristic reaction of succinic acid. 



Combustions of the pure material dried at 110° C, resulted as follows: 



(I) Weight of sample, 0.2378 gm. ; H.^O, 0.1047 g"!-! CO2, 0.3556 gm. 



(II) Weight of sample, 0.3063 gm. ; HjO, 0.1356 gm. ; CO2, 0.4530 gm. 

 Calculated for C4H6O4; C, 40.66 per cent; H, 5.12 per cent. 



Found: (I) C, 40.78 per cent; H, 4.94 per cent. (II) C, 40.33 per cent; H, 

 4.96 per cent. 



Titration with sodium hydroxid (NaOH) gave the following results: 



(I) 0.1776 gm. acid required 30.037 cc. NJio NaOH. 



(II) 0.1453 g"^- ^cid required 24.424 cc. N/io NaOH. 

 Calculated for C4Hg04; replaceable H, 1.707 per cent. 

 Found: (I) 1.703 per cent; (II) 1.692 per cent. 



A silver salt was prepared and analyzed, giving the following data: 



(I) 0.4809 gm. salt gave 0.3119 gm. Ag. 



(II) 0.4818 gm. salt gave 0.3126 gm. Ag. 

 Calculated for C4H404Ag2; Ag 65.02 per cent. 

 Found: (I) 64.86 per cent; (II) 64.88 per cent. 



' Reference is made by number (italic) to "Literature cited," p. 22S. 



