198 CHEMICAL AND METABOLIC ACTION NOT MUTUAL. 



tions for action independent of spontaneity, and the mere cir- 

 cumstance of vivid molecular movement can be paralleled in 

 all liquids, especially where chemical changes are going on. To 

 peer then farther in imagination into the constitution of those 

 spherules, we may picture to ourselves the very elements 

 resolved into their component atoms, and these, rearranged into 

 clusters and constellations of molecules of relatively enormous 

 size and complexity. These latter, again, representing systems 

 made up of atoms corresponding to suns, planets, and satellites, 

 all revolving rapidly in their orbits, while possibly also, as sup- 

 posed by Williamson in solutions of salts, some atoms may be 

 passing from one molecule to another. In this state of matter,, 

 so different from the simpler inorganic state, we may suppose 

 new laws of vito-chemical or metabolic combination. In all 

 chemical combination double decomposition and recombination 

 with formation of a third substance into which both factors 

 enter in exact proportion, are the rule, while here, when a 

 chemical substance pabulum is placed in contact with the 

 living matter, the latter is not decomposed but the pabulum is 

 instantly taken to pieces possibly its ultimates even resolved 

 and incorporated with the living matter, from which it 

 emerges in a totally different state of chemical combination 

 partly as tissue or secretion, and partly as effete products, while 

 any surplus force comes out as heat or mechanical movement. 



Leaving what is merely speculative on the constitution of the 

 living molecules, it is obvious that between ordinary matter and 

 such a kind of material composed as protoplasm is, there can be- 

 no possible relation of a chemical kind at all ; and the only rela- 

 tions the living matter can have with matter in the ordinary state 

 and with force are those of pabulum, conditions, and stimuli. To 

 the living matter there are no acids nor alkalies, no solvents, no 

 astringents, no fats or soaps, no ferments or catalytic agents, 

 no sugars nor alcohols, no>lbumen, fibrin, gelatine or the like to 

 act upon it in any way, resembling in the least their action on 

 dead matter, but only as pabulum and stimuli. Probably 

 moisture alone acts purely as a condition, but nearly all kinds 

 of pabulum, including oxygen, act also as stimuli, while some 

 agents generally recognized as stimuli, act in that capacity 



