90 APPENDIX. 



(or porcelain) dish at 105 degrees until dried to a con- 

 stant weight, then weighed and the results reckoned on 

 the whole fluid mass. 



5. Carbohydrates:. From the solution saved from the 

 extract determination, a measured amount, about 200 

 c. c. is mixed with 5 grams of concentrated H2SO4 

 (or 18 c. c. of concentrated hydrochloric acid) and 

 boiled 5 hours in a flask provided with a reflux conden^ 

 sen* Thereby all the carbohydrates are inverted, that is, 

 they are transformed into reducing sugars and can be de- 

 termined according to methods given for milk sugar. The 

 inverted cooled solution is brought at room temperature 

 to a stated volume, an aliquot part of the same taken and 

 treated as for the milk sugar determination given on 

 page 50. 



*Such prolonged heating at such high temperature is usually 

 inadvisable and unnecessary. The common practice at present 

 is to heat for 15 minutes at 68° — 70° C. See bulletin No. 46, U. 

 S. Dept. of Agr., Div. of Chem., p. 31. — Translators. 



