ACCESSORY FOOD BODIES 103 



o'i8 gramme of bacterized peat were after six weeks' 

 growth double the size of similar untreated plants, 

 and it was noted that flower production and root 

 development were promoted equally with increase 

 of foliage. In view of what was then known as to 

 the effect of vitamines on the growth of animals and 

 on their health, it was decided as a preliminary 

 experiment to follow the method adopted by Cooper 

 and Funk for the isolation of beriberi vitamine. 

 A considerable quantity of bacterized peat was 

 extracted with absolute alcohol in a shaking machine 

 for three hours, and the extract was filtered off and 

 evaporated to dryness in vacuo. The residue was 

 taken up in distilled water, 'filtered, and to the filtrate 

 Sulphuric acid was added until the concentration of 

 the latter reached 5 per cent. A slight precipitate 

 of Humic acid was filtered off, and to the filtrate an 

 excess of a 30 per cent, solution of Phosphotungstic 

 acid was added. The whole was then left to stand 

 overnight, when the liquid was decanted off through 

 a filter, the precipitate repeatedly washed with a 

 5 per cent, solution of Sulphuric acid, and finally 

 decomposed with an excess of Baryta. The liquid 

 was filtered off from the precipitate of Barium 

 phosphotungstate, and the filtrate, freed from the 

 last traces of Baryta by means of a very dilute 

 solution of Sulphuric acid, was evaporated to dryness 

 in vacuo. From 7 kilogrammes of bacterized peat 

 the amount of dry substance thus obtained amounted 

 to 12*0096 grammes. For purposes of testing, this 

 dried residue was dissolved in such a way that the 

 amount extracted from 10 grammes of the original 



