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lime water. When complete solution was attained, the alkaline solution 

 was carefully neutralized with .2 per cent. HC1. 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. HC1. This 

 was filtered, dissolved and precipitated, the whole process being repeated 

 fifteen times. Samples of the fifth, tenth and fifteenth precipitate were re- 



