14 GENERAL PEOPEETIES OF LIVING MATTER. 



albuminates, comprehending by these terms both the living 

 matter and its derivations or products. According to Hoppe- 

 Seyler, the proteinates are composed of : carbon, 51.5 to 54.5 per 

 cent. ; oxygen, 20.9 to 23.5 per cent. ; nitrogen, 15.2 to 17.0 per 

 cent, j hydrogen, 6.9 to 7.3 per cent. ; and sulphur, 0.3 to 2.0 per 

 cent. 



Manifestation of Life. While chemical examination has re- 

 vealed very little of the intimate nature of living matter, we 

 know certain properties to be essential to living matter as long 

 as it is really alive, and we know, also, some of its morphological 

 features, to as great an extent as direct observation is possible with 

 our best modern magnifying apparatus. The physiological proper- 

 ties are visible in every moving and growing organism, and they 

 must be attributed to the minutest living particles as well as to 

 the whole organism. We consider living matter alive only so 

 long as it exhibits to us certain physiological properties j when 

 motion and reproduction cease, it is dead. Life is evidently a 

 peculiar kind of motion of the molecules (plastidules) of living 

 matter, of a relatively short duration. A change of the motion 

 is disease ; cessation is death. The chemical changes of living 

 matter are different during life and death ; the former are mani- 

 fested by motion and reproduction, the latter by decomposition, 

 which means simplification of the atomic construction. The 

 shape of living matter is changed by decomposition, but by 

 preservation we succeed in retaining the shape of the substance, 

 which we know was once the seat of life, and microscopic 

 morphology is largely based upon observation of dead but pre- 

 served living matter. 



Properties of Living Matter. The physiological properties are 

 mainly two: motion and reproduction viz., the capability of 

 producing its own kind. In speaking of the motion of living 

 matter, we do not mean the motions to which every substance is 

 subject, and of which light, heat, electricity, etc., are peculiar 

 manifestations. There are certain forms of motion dependent 

 on the contractility or irritability of living matter which do not 

 occur in inorganic bodies, nor in organic matter after it has 

 ceased to be alive. This kind of motion enables living matter to 

 work, at least to a certain limited degree, against the law of 

 gravity. It is controlled by complicated laws, which we term 

 the " will and the " spontaneity " of living matter. According to 

 M. Foster, the term " automatic motion is preferable to " spon- 

 taneous," inasmuch as it does not necessarily carry with it the 



