VITALITY 381 



same tendency is so great that ■where an isolated group is found it is thought to 

 be probable that the links of connection are missing only because they are ex- 

 tinct, or are not yet discovered. 



It is important for our purpose to notice the manner in which one group of 

 living things passes into another. It will generally be found that the transition 

 is not effected by the shading off or blending of the extreme edges of the groups, 

 but by a kind of interlocking of the one into the other. The junction often 

 resembles that of the sea and the land on the coast of Norway, where in many 

 places it is hard to say whether it is the sea that runs far into the land or the 

 liud that runs far into the sea. Thus, judged by one set of characters, an or- 

 ganic form may not only be a vegetable, but even hold a somewhat high place 

 in the vegetable kingdom, while, judged by another set of characters, the same 

 creature may not only be an animal, but have its place by no means on the 

 confines of the animal kingdom. 



Discoveries relating to the allotropic forms of matter and the correlation of 

 the imponderable forces warrant the same conclusion as to the close affinity 

 subsisting between inorganic things. 



In fact, that "nature does not proceed by a leap" might seem to be a rule 

 that lacks the criterion of an exception; yet there is an exception, and a striking 

 one; limits have given way in all directions, yet tliere is one that stands out as 

 i^hiirply and as distinctly as ever — that, namely, which divides animated things 

 from those which are inanimate. No form of matter tliat is not animate exhibits 

 anything approaching to thi; phenomena of life. Of course, none but a super- 

 ficial observer would suggest the process of crystallization, or the dendritic 

 appearances of some metals, or the moss-like forms seen in agates, as excf^ptions. 

 Neither can any instance of a degradation towards the character of inoiganic 

 matter be found in the very lowest forms of life, in the protozoa, or the sponges, 

 or the nullipores, or the fungi, the algae, the confervas, or even in thi? single living 

 vegetable cell. 



Now, if the vital principle be analogous to any known form of matter or 

 force, this solitary case of a great leap taken by nature is incongruous with 

 all that we know of her other proceedings. If, indeed, the presence of life in- 

 dicates the introduction of something entirely new, then we have a reason for 

 the leap. But if not, the facts we have considered appear to be inconsistent 

 with the hiatus between animate and inanimate things. If life be made up of 

 forces similar to those which act in various ways both on organic and on inor- 

 j;anic matter, we might expect to find the transition from things inanimate to 

 things animate the same in character with all other transitions in nature; the 

 border land would be occupied with semi-animate materials and semi-mineral 

 vegetables or animals, with instances of equivocal life and products of doubtful 

 organization. Whereas, from the highest to the very lowest organism, even to 

 the primordial utricle and cell, the phenomena of life are distinct and unques- 

 tionable. It is trut! that geologists have to deal with certain form.-* of doubtful 

 organization found in the lowest rocks, but in these instances the difficulty arises 

 from the changes through which the fossils have passed. There may b^ reason 

 to doubt whether certain appearances truly indicate organic remains; but thern 

 is nothing to indicate that life, in the Silurian ages, was less distinct than it is 

 now. 



The above argument for the specialty of the vital principle, derived from the 

 unparalled solution of continuity in nature just at the point where life commences, 

 demands for its full illustration rather a volume than a mere notice in a brief 

 paper. Its force, if it have any, is evidently acquired from facts revealed by the 

 very researches which have led sorn'; to form an opposite conclusion. 



Again, if vitality is analogous to, or correlative with, the known forces, we 

 might expect to find at aM events some resemblance existing between their re- 

 spective properties and modes of action Now the results of the action of heat, 



