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ANALYSIS OF THE TOMATO. 
1. The glair of the ripened fruit was subjected to pressure in a 
clean muslin cloth, and the acid juice obtained was then boiled in 
a Berlin evaporating dish, to coagulate the albumen present. Of 
this there was a considerable quantity, but it was easily separable 
by heat — the acid present no doubt facilitating the process. 
2. The liquor was then filtered through paper, limpid and color- 
less. Tested with litmus paper, it proved to be strongly acid. 
This, indeed, was obvious to the taste. 
3. This acid liquor was neutralized with ammonia. Both this 
alkali and potash gave to the liquor a wine-red color, which was 
discharged by an addition of the tomato juice, or other acid. 
4. To the neutralized liquor (3) was added chloride of lime. 
This dissipated the wine-red color, but produced no precipitate. 
Ebullition in a test-tube, however, for a few moments, yielded a 
white precipitate. This experiment indicated the absence of oxalic, 
malic, tartaric and paratartaric acids, and the presence of citric 
acid. 
5. The white precipitate (4) was soluble in chloride of ammo- 
nium. This solution boiled, again yielded a white precipitate. This 
reaction with sal-ammoniac afforded another evidence of the ab- 
sence of paratartaric (racemic) acid. 
6. The ebullition of 4 was continued until no more precipitate 
fell. To the decanted liquor, alcohol was added, but the liquid re- 
mained clear. This furnished additional evidence of the absence 
of malic acid. 
7. The acid juice (2) was neutralized with lime water. No 
precipitate appeared. On boiling, flocculi were produced, and 
these were redissolved on cooling. This reaction indicates citric 
acid, to the exclusion of almost every other organic acid. 
8. The acid juice (2) was treated with acetate of lead. A very 
copious, heavy, white precipitate instantly fell. This precipitate 
was readily soluble in citrate of ammonia; thus again denoting the 
presence of citric acid. 
9. To the filtered, neutralized juice, was added sesqui-chloride 
of iron. The liquid assumed a yellowish-green color, and remain- 
ed perfectly transparent. The absence of any reaction in this case 
excludes the idea of tannic, gallic, acetic and benzoic acids being 
present. 
Thus, then, I determined the certain existence of citric acid in 
