100 SELECTED ESSAYS FROM LAY SERMONS 



that, by appropriate processes, it may be resolved into 

 bonic acid and quicklime. If you pass the same carb 

 acid over the very quicklime thus obtained, you will ot 

 carbonate of lime again; but it will not be calc-spar, 

 anything like it. Can it, therefore, be said that chen ^ 

 analysis teaches nothing about the chemical composi 

 of calc-spar? Such a statement would be absurd; but 

 hardly more so than the talk one occasionally hears al 

 the uselessness of applying the results of chemical ana 

 to the living bodies which have yielded them. 



One fact, at any rate, is out of reach of such refineme 

 and this is, that all the forms of protoplasm which 1 

 yet been examined contain the four elements, carl 

 hydrogen, oxygen, and nitrogen, in very complex un 

 and that they behave similarly towards several reage , 

 To this complex combination, the nature of which . 

 never been determined with exactness, the name of I 

 tein has been applied. And if we use this term with s . 

 caution as may properly arise out of our comparative ig 

 ranee of the things for which it stands, it may be truly si 

 that all protoplasm is proteinaceous, or, as the white, 

 albumen, of an egg is one of the commonest examples c 

 nearly pure proteine matter, we may say that all liv 

 matter is more or less albuminoid. 



Perhaps it would not yet be safe to say that all form^ 

 protoplasm are affected by the direct action of elec 

 shocks; and yet the number of cases in which the contr 

 tion of protoplasm is shown to be affected by this agei 

 increases every day. 



Nor can it be affirmed with perfect confidence, that • 

 forms of protoplasm are liable to undergo that pecub 

 coagulation at a temperature of 40^-50° centigrade, whi 

 has been called "heat-stiffening," though Kiihne's beam 



