306 EXPERIMENTS [CH. XVI 



(2) Compare the diastatic power of malt and un- 

 germinated barley. 



(3) Shew that cold water extract of malt has diastatic 

 power, but that cold water extract of leaves of barley when 

 filtered clear has little or no diastatic power. 



(4) Compare the diastatic power of the leaves of 

 Pisuvi sativum and Trifolium pratense. 



Experiments on Invertase and Glycase. 



(1) Shew that water in which living yeast cells have 

 been suspended has no invertive action on cane-sugar 

 when filtered quite free from yeast cells, but that water in 

 which yeast cells have been killed and crushed has inver- 

 tive power even when filtered quite clear. 



(2) Shew that the addition of finely ground maize 

 suspended in water transforms maltose into dextrose. 



Glucoside Ferments. 



Shew that emulsion of bitter almonds will produce 

 saligenol from salicin. 



Diastase. 



(1) Prepare a specimen of solid diastase by the 

 method given on p. 305. 



Shew that the specimen is soluble in water and that 

 it will produce dextrins and maltose from starch. 



(2) Make aqueous extracts of malt and barley as 

 described for preparation of diastase. 



Compare the diastatic power of the extracts by their 

 action on soluble starch. 



