536 DISSOLUTION. 



motion of units into the motion of aggregates, which con- 

 stitutes evolution, dynamically considered; and we have 

 also, though in a subtler sense, a transformation of the 

 motion of aggregates into the motion of units. Still it is 

 not thus shown that organic dissolution fully answers to the 

 general definition of dissolution the absorption of motion 

 and concomitant disintegration of matter. The disintegra- 

 tion of matter is, indeed, conspicuous enough; but the ab- 

 sorption of motion is not conspicuous. True, the fact that 

 motion has been absorbed may be inferred from the fact 

 that the particles previously integrated into a solid mass, 

 occupying a small space, have most of them moved away 

 from one another and now occupy a great space; for the 

 motion implied by this transposition must have been ob- 

 tained from somewhere. But its source is not obvious. A 

 little search, however, will bring us to its derivation. 



At a temperature below the freezing point of water, de- 

 composition of organic matter does not take place the 

 integrated motions of the highly integrated molecules are 

 not resolved into the disintegrated motions of their com- 

 ponent molecules. Dead bodies kept at this temperature 

 for an indefinitely long period, are prevented from decom- 

 posing for an indefinitely long period: witness the frozen 

 carcases of Mammoths Elephants of a species long ago 

 extinct that are found imbedded in the ice at the mouths 

 of Siberian rivers ; and which, though they have been there 

 for many thousands of years, have flesh so fresh that when 

 at length exposed, it is devoured by wolves. What now is 

 the meaning of such exceptional preservations? A body 

 kept below freezing point, is a body which receives very 

 little heat by radiation or conduction; and the reception of 

 but little heat is the reception of but little molecular motion. 

 That is to say, in an environment which does not furnish it 

 with molecular motion passing a certain amount, an organic 

 body does not undergo dissolution. Confirmatory 



evidence is yielded by the variations in rate of dissolution 



