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tallised from ether, and further identified by the tests mentioned. The following results were obtained: Weight of crude residue. Swedish filter paper 3.0 crystallised at once by 'sowing.' Ordinary cotton 3.3 " " Mercerised cotton 2.1 " " Straw cellulose[6] 2.3 " " Laevulose 2.2 " " Inulin 1.3 " " Potato starch 0.37 " " Cane sugar 0.85 " " Dextrose 0.33 uncrystallisable. Milk sugar 0.37 " Glycogen 0.34 " Galactose 0.34 " The products from _dextrose_, _milk sugar_, and _galactose_ absolutely refused to crystallise even when extracted with ether and again evaporated, or by 'sowing,' stirring, &c. The _glycogen_ product deposited a very small amount of crystalline matter on standing, but the quantity was too minute for examination; moreover, it refused altogether to crystallise in contact with the aldehyde. It may fairly be stated, therefore, that these last four substances give absolutely negative results as regards the formation of omega-brommethylfurfural; if any is formed, its quantity is altogether too small to be detected. The specimen of _starch_ examined was freshly prepared from potato, and purified by digestion for twenty-four hours each with _N_/10 KOH, _N_/4 HCl, and strong alcohol; it was then washed with water and allowed to dry in the air. It will be seen that this substance gave a positive result, but that the yield was extremely small, and might yet be due to impurity. Considering the importance of the behaviour of starch, for the purpose of drawing general conclusions from these observations, it was thought advisable to make further experiments with specimens which could be relied upon, and also to investigate the behaviour of dextrin. This the authors have been enabled to do upon a series of specimens specially prepared by C. O'Sullivan, and thus described by him: 1. Rice starch, specially purified by the permanganate method. 2. Wheat starch " " " 3. Oat starch, contains traces of oil, washed with dilute KOH and dilut
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