COMPOSITION OF GREEN RYE AND RAPE. 5 



tion was repeated a third time ; the cellular fibre on the cloth by 

 that time was nearly white, and, after a few washings with water, 

 imparted nothing soluble to water. Thus washed clean, the im- 

 pure fibre was dried in the water-bath, and its weight ascertained. 



A portion of the dried impure fibre was subsequently reduced to 

 ash in a platinum capsule, and by this means the proportion of 

 insoluble inorganic matters attached to the fibre was determined. 

 The ash of the fibre consisted principally of carbonate and phos- 

 phate of lime, and contained, likewise, some sulphate of lime, 

 magnesia, and silica. 



Another weighed portion of the finely -powdered and dried 

 impure fibre was employed for a nitrogen determination. The 

 amount of nitrogen was ascertained in the usual way, by com- 

 bustion with soda-lime, and, by calculation from the amount of 

 nitrogen, that of the insoluble protein compounds contained in 

 young rye and rape were determined. 



A third portion of the impure fibre was digested with alcohol 

 and ether, in order to deprive it of any remains of fatty matter 

 which may have been attached to it. 



The amount of insoluble protein compounds and inorganic 

 matters thus obtained, being deducted from the impure fibre, 

 exhausted with alcohol and ether, furnished by calculation the per- 

 centage of pure cellular fibre. 



3. Determination of Soluble Albumen. The united liquids which 

 passed through the linen cloth were raised to the boiling-point in 

 a glass beaker, when a considerable quantity of greenish-coloured 

 flakes of coagulated albumen was separated. These flakes were 

 allowed to settle for twenty-four hours. After that time the 

 supernatant liquid, now become clear, was passed through a 

 weighed filter, on which the coagulated albumen was also col- 

 lected. The albumen was washed on the filter with distilled 

 water, dried at 212 Fahr., then digested with alcohol and ether, 

 and finally dried in the water-bath until it ceased to lose weight. 

 The greenish colour of the albumen is due to some chlorophyll, 

 the greater part of which is removed by digestion in alcohol and 

 ether. 



A few drops of acetic acid added to a portion of the liquid from 

 which the albumen had been separated by boiling and filtration, 

 produced no change, and thus showed the absence of casein in the 

 juice of the plants under consideration. 



4. Determination of gum, pectin, and salts, insoluble in alcohol. 

 In the liquid from which soluble albumen was separated by 

 boiling and filtration, gum, pectin, sugar, and soluble inorganic 

 salts, besides traces of other less important compounds, the quan- 

 titative determination of which was omitted, were present. 



The separation of the sugar and salts soluble in alcohol from 

 gum, pectin, and salts insoluble in alcohol, was effected as follows : 



