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lime water. When complete solution was attained, the alkaline solution 
was carefully neutralized with .2 per cent. HCl. The neutral point was 
determined by litmus paper that was fresh and quite sensitive. No mu- 
coid precipitated in the neutral solution, but it was strained through silk 
for the sake of uniformity of conditions. Duplicate samples were taken to 
determine the mucoid content before heating. The major portion of the 
solution was gently boiled under a water condenser. Every half hour, 
about 100 cc. of the solution was removed, allowed to cool rapidly without 
any loss of water vapor, filtered and duplicate aliquot portions of the fil- 
trate were used for acid precipitation of the mucoid content. 
By way of results, it was noticed that continued boiling had a fatal 
effect on the mucoid. At first the solution became turbid. At the end of 
the first half hour’s heating, there was a nice coagulum in the solution. 
This increased gradually until about the fourth hour, when there was a 
heavy coagulum throughout the solution. During the process of continued 
heating, the solution remained neutral without the addition of any alkali 
or acid. The longer the heating continued, the more rapidly the solution 
filtered. The first few filtrates were very slightly turbid, but the tur- 
bidity gradually decreased to water-clearness in the last few filtrates. 
With regard to the filtrates, on treatment with dilute acid it was 
found that with the initial precipitations, less mucoid was recoverable 
than was obtained from the unboiled mucoid solution. The amount of 
mucoid precipitated gradually decreased as the experiment advanced and 
finally filtrates were obtained from which no mucoid could be precipitated 
with an excess of dilute acid. This was coincident with the heavy coagu- 
lum in the major portion of the solution. This experiment seemed to show 
conclusively that mucoid did coagulate on heating in the presence of neutral 
salts. It was deemed useless to try to separate a coagulable albumin from 
mucoid by this method. 
The work done in this research was carried out, using a mucoid sample 
that had been purified by solution in alkali and precipitation by acid, this 
alternation for eight times. To test whether the eighth precipitate might 
be different from the sixth or tenth precipitate, or any other precipitate in 
the series, about 20 grams dry mucoid that had been precipitated probably 
twice, were dissolved in several liters of half-saturated lime water, strained 
through silk and precipitated with a slight excess of .2 per cent. HCl. This 
was filtered, dissolved and precipitated, the whole process being repeated 
fifteen times. Samples of the fifth, tenth and fifteenth precipitate were re- 
