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present. We, therefore, carried out another series of tests with 

 extracts from rabbits' small intestines, which were always much 

 more active than extracts of cats' intestines. Our procedure was the 

 following : 



The rabbit was killed by a blow on the neck and dehematized 

 from the carotids; the small intestine was cautiously detached from 

 the mesenterium and subsequently put in an abundant qaantity of 

 warm Tj'rode-solution. Hereafter the gut was perfused with this 

 fluid three or four times and every time transferred to another 

 dish with fresh Tyrode-tluid. Afler being tied up on both ends and 

 rinsed again it was suspended in 75 c.c. of water at 38°. The gut 

 was taken out after an hour. A slightly alkaline reaction of the 

 colourless and perfectly limpid aqueous extract was now noticeable. 

 By infusion of carbonic acid or an admixture of some drops of 

 1/10 nHCl the reaction to litmus is made neutral, and rapidly boiled 

 up. A flocculent precipitate is thrown down and on filtration there 

 ensues a clear solution which (foaming being precluded) is evaporated 

 down to a very small volume under a diminished pressure at 50°. 

 A subsequent admixture of 25 cc. of methylalcohol produces a 

 precipitate which contains little or nothing of the active substance 

 and can be readily removed by filtration. The alcoholic solution 

 thus obtained, possesses in undiminished degree the activity of the 

 primary aqueous extract. 



After removing the greater part of the methylalcohol by distillation, 

 acetone is added to 4 — 5 times the quantity of the extract, which 

 gives a large precipitate, containing only a small portion of the 

 active constituent. After filtration the solution is evaporated down 

 to a small volume under a lower pressure and subsequently placed 

 in a vacuum-exsiccator. The pale yellow residue is then repeatedly 

 extracted with small amounts of absolute alcohol until KI^, added 

 to a few drops of the filtrate, arrests the precipitation. As Stanêk 

 has pointed out this is a delicate reaction on cholin. By saturating, 

 this solution with sublimate a white precipitate is produced that, 

 after some hours, is filtered by suction and washed out first with 

 an alcoholic sublimate solution and subsequently with absolute alcohol. 

 The precipitate is then extracted with a little warm water, acidulated 

 with a drop of hydrochloric acid. After cooling down, or if necessary 

 concentrating, lightly tinged crystals segregate in the shape of little 

 columns. After repeated ciystallization the melting point was found 

 to be 244°; when mixed with the mercurous double salt of pure 

 cholin (melting point 246°) we found 244°— 245°. To identify our 

 experience still further platinum-salt was prepared, which melted at 



