104 SELECTED ESS A YS FROM LA Y SERMONS 



assimilative powers of the animal world cease. A solution 

 of smelling-salts in water, with an infinitesimal propor- 

 tion of some other saline matters, contains all the elemen- 

 tary bodies which enter into the composition of protoplasm; 

 but, as I need hardly say, a hogshead of that fluid would 

 not keep a hungry -man from starving, nor would it save 

 any animal whatever from a like fate. An animal cannot 

 make protoplasm, but must take it ready-made from some 

 other animal, or some plant — the animal's highest feat of 

 constructive chemistry being to convert dead protoplasm 

 into that living matter of life which is appropriate to itself. 



Therefore, in seeking for the origin of protoplasm, we 

 must eventually turn to the vegetable world. A fluid con- 

 taining carbonic acid, water, and nitrogenous salts, which 

 offers such a Barmecide feast to the animal, is a table richly 

 spread to multitudes of plants; and, wdth a due supply of 

 only such materials, many a plant will not only maintain 

 itself in vigour, but grow and multiply until it has increased 

 a million-fold, or a million million-fold, the quantity of 

 protoplasm which it originally possessed; in this way build- 

 ing up the matter of life, to an indefinite extent, from the 

 common matter of the universe. 



Thus, the animal can only raise the corr^plex substance of 

 dead protoplasm to the higher power, as one may say, of 

 living protoplasm; w^hile the plant can raise the less complex 

 substances — carbonic acid, water, and nitrogenous salts — 

 to the same stage of living protoplasm, if not to the same 

 level. But the plant also has its limitations. Some of the 

 fungi, for example, appear to need higher compounds to 

 start with; and no known plant can live upon the uncom- 

 pounded elements of protoplasm. A plant supplied with 

 pure carbon, hydrogen, oxygen, and nitrogen, phosphorus, 

 sulphur, and the like, would as infallibly die as the animal 



