5O PHYSIOLOGICAL CHEMISTRY. 



test with Fehling's solution. Dextrose has been formed from the 

 cellulose by the action of the acid. 



4. Schweitzer's Solubility Test. Place a little absorbent cotton 

 in a test-tube, add Schweitzer's reagent/ and stir the cellulose with 

 a glass rod. When completely dissolved acidify the solution with 

 acetic acid. An amorphous precipitate of cellulose is produced. 

 Schweitzer's reagent is the only solvent for cellulose. 



REVIEW OF CARBOHYDRATES. 



In order to facilitate the student's review of the carbohydrates, 

 the preparation of a chart similar to the appended .model is recom- 



MODEL CHART FOR REVIEW PURPOSES. 



mended. The signs + and may be conveniently used to indicate 

 positive and negative reaction. Only those carbohydrates which 

 are of greatest importance from the standpoint of physiological 

 chemistry have been included in the chart. 



1 Schweitzer's reagent is made. by adding potassium hydroxide to a solution 

 of cupric sulphate which contains some ammonium chloride. A precipitate of 

 cupric hydroxide forms and this is filtered off, washed, and 3 grams of the 

 moist cupric hydroxide brought into solution in a liter of 20 per cent ammonium 

 hydroxide. 



