486 ANNUAL EECORD OF SCIENCE AND INDUSTRY. 



The result of many inquiries on his part is to show that 

 the solids left by evaporation of cow's milk vary compara- 

 tively little, in different animals or in different seasons, and 

 he thinks that a range of from 11.5 to 12 per cent, expresses 

 about the average amount of these solids. 1 A, October IS^ 

 1872,187. 



HAEDENING OF DEIED PEASE IN BOILING. 



While some pease become soft in boiling, others become 

 horny and hard, and it has been a question whether this is 

 due to the pease or to the water. Professor Ritthausen ex- 

 amined two samples of pease, one said to become soft on boil- 

 ing, the other hard, and on boiling them in distilled water 

 found these characters substantiated. The analysis of their 

 ashes gave : 



Soft. Hard. 



Phosphate of lime 10.77) ^^^ qi ^^'^^l 2r 06 



Phosphate of magnesia. . . 8.14) * 16.55) 



Phosphate of potassa 59.74 37.43 



Sulphate of potassa 8. 10 14.80 



Chloride of potassium 4.72 6.23 



Potash... 11.47 



Phosphoric acid 4.43 



From this we see that the soft-boiling pease contain a con- 

 siderably greater amount of phosphate of potassa, smaller 

 percentage of phosphatic earths, and more phosphoric acid 

 than the other kind, which, for their part, are richer in the 

 earth-phosphates, poorer in other phosphoric compounds, and 

 contain an excess of potash. 



In the action of water on those pease poor in phosphoric 

 acid, that harden on boiling, the legumine, which is present in 

 large quantity, although partially combined with the excess 

 of potash, has also its function. It is decomposed with the 

 separation of a compound of lime or magnesia, which be- 

 comes horny on heating, and brings about the hardening re- 

 ferred to. Cold water extracts from the meal of those j^ease 

 that boil soft 4.24 per cent, of soluble legumine, while from 

 the hard-boiling kinds only 1.73 per cent, can be derived. 

 The difference in the amounts of nitrogen and sulphur was so 

 slight that the hardening could not be ascribed either to a 

 larger amount of dlbumen or of sulphuric acid. Some kinds 

 of pease, however, represented as hardening on boiling, soft- 



