BIOLOGY. 275 



ties, canals, and spaces, in the interior of the body are due to the 

 same progress, and that the faihare or arrest of it may be the cause 

 of many of the so-called adhesions of seams and other surfaces, of 

 the imperforate condition of canals, and the union of parts that 

 should be free." 



"It is quite clear that what we call 'Chemistry,' with its 

 attendants, heat and eleetricity, plays a most important part in the 

 animal machine ; and, probably, more information as to the nature 

 of the organic processes is to be expected from their chemical 

 study than in any other way. We have found out that there is a 

 very close relation between a complete atomic formula and the 

 vital i^i-ocesses, the amount of chemical tension which is expressed 

 by the former being commensurate with the character of the lat- 

 ter, and the amount of chemical change which takes place in the 

 textures being commensurate with the activity of the vital pro- 

 cesses. There seems good reason to believe that a muscular fibre 

 is the container of a given amount of chemical force compressed by 

 the medium of a high chemical formula, and existing, therefore, 

 in a high state of tension ; that during its contraction the com- 

 pressed force is set free by the decomposition of its structure — 

 that is, by the resolution of its component elements, chiefly by a 

 process of oxidation, to a lower formula or a state of lower ten- 

 sion, at the same time that heat is evolved and electrical changes 

 take place; though the latter are not yet distinctly defined. It 

 is impossible, therefore, to avoid the application here of the doc- 

 ti'ine of contractile force, which is being so clearly worked out in 

 the organic world, and wliich seems to be the greatest advance 

 that has for some time been made in our knowledge of the laws of 

 matter. We can scarcely doubt that the chemical force whicli is 

 set free during the decomposition attendant upon muscular action is 

 the equivalent of the contractile force that is evinced, and of the 

 heat that is evolved. In other words, a muscle may be regarded 

 as the medium by which force is accumulated, rendered latent, or 

 condensed in a condition of high chemical tension, and is, from 

 time to time, as occasion may require, set free and converted into 

 muscular or contractile force and heat." 



Change from Life to Death. — In relation to the transition from 

 life to death, a change which takes place under ordinai'y circum- 

 stances in the most delicate, insensible manner, — so that it is 

 impossil)le to say when and how life ends and death begins, — he 

 referred to the mode in which the parts of the ultimate tissue of 

 the body become changed and cease to exist. Even in the in- 

 stance of the cuticle, a structure comparatively under the eye as 

 we watch the transition of the spherical deejjer components to 

 the flattened forms of the superficial strata, and the disintegra- 

 tion of the latter, we are at a loss to decide where living force 

 ends. Clearly, it is not by an abrupt disintegration or solution, 

 but by some slow insensible process, which savors rather of ato- 

 mic change than of destruction. "Then one is inclined to ask, 

 if tlie passage froiu the living to the unliving condition be of this 

 insidious, inappreciable nature, may there not be a converse of 

 a like kind, an insensible origination of, or conversion into life 



