21 
is not.” These properties are, — first, the chemical consti- 
tution of living matter, as it invariably contains a par- 
ticular compound of carbon, water, and nitrogen, only found 
in organic matter, which, is the chief constituent of the 
“ protoplasm ” of which the organism is constructed. The 
second distinctive property of living matter is its universal 
disintegration and waste by oxidation, and its re-integration, 
not by external accretion, as a crystal increases in size, but by 
introsusception of fresh and suitable material. The third pro- 
perty is its tendency to undergo cyclical changes ; each indi- 
vidual form, when it has passed through these changes, ceasing 
to possess the properties of living matter, though continuing 
and multiplying its existence by its seed or other portions of 
itself, which, in their turn, all undergo the same cycle of 
changes. No other form of matter whatever (I still quote from 
Professor Huxley) exhibits these properties, or any approach 
to the remarkable phenomena of the two last properties. 
Living matter has indeed other properties peculiar to itself, 
though not so distinctly marked. Its activities depend more or 
less on moisture and heat. Complete desiccation is fatal to living 
matter, as are also extremes of temperature. Besides these, 
organisation, or the possession of special instruments for special 
purposes, is usually characteristic of these existences, and is 
often, even in what we might consider a simple form, exceed- 
ingly complicated. And, we may add, in living matter a new 
idea is introduced into Nature, that of an existence composed 
of many very different molecules of matter, which yet is one 
individual. 
10. We have, then, here, in the order of the Universe, a 
class of existences definitely marked off from the rest by the 
possession of properties, different not only in degree but in 
kind, from those of other material existences. Science, intent 
as it is on tracing unity, confesses that it can find “ no kind 
of link ” between them. Is there, then, a real break in unity 
because we cannot find continuity in Nature ? If we believe 
in that rational basis of unity beyond Nature which Religion 
supplies, we shall not wonder that Science cannot trace the 
continuity here, when continuity cannot be traced even among 
the constituents of dead matter. The same remark applies 
to the distinctions between the main divisions in this general 
class of living existences. The tendency of the scientific 
mind, whenever it shrinks from recognising a deeper founda- 
tion of the unity and order of the universe than any that 
Nature can supply, is, in disregard of distinctions which 
unprejudiced reason recognises as fundamental, to assume that 
the vegetable, animal, and human types, are all connected 
