JUNE 1, 1899] 
NATURE 
107 
the correctness of its major contention. We may be 
said to pass from chemical speculation to a solid 
chain of facts, which doubtless will be strengthened and 
lengthened as time goes on. In all these changes we 
seem to be in the presence of a series of what chemists 
call polymerisations, that is, roughly, a series of doublings. 
The greater complexities may also have been brought 
about by the union of different substances. In either 
case, as temperature is reduced, we get a possibility of 
combinations which was not present before ; so that more 
and more complex forms are produced. 
That brings us to a possibility of considering the pro- 
cesses of inorganic evolution in relation to those of organic 
evolution. I have already referred to the fundamental 
difference in the conditions. We had a running down of 
temperature which no one could define in the case of the 
stars ; in the case of the organic evolution going on under 
our present conditions, we cannot be very much removed 
from the temperature conditions of the Cambrian form- 
ations. That isa point which I have made before, and 
it is important to insist upon it; clearly there cannot 
have been any very great change of temperature during 
the whole cycle of organic life. Previous to it we have 
found complexity brought about by doublings and com- 
binations, the result being, as I have already mentioned, 
more complex forms. Of course, at the dawn of organic 
life on the surface of the earth there may have been 
residua of the earlier chemical forms; that is to say, 
not all the elements which we found in the hottest 
stars had combined to form the substances of which 
the earth was composed. However this may be, the 
work of organic evolution, unlike that of inorganic evolu- 
tion, must have been done under widely different 
temperature conditions, but the result has been the 
same ; it has since provided us with another succession 
of forms getting more complex as time has gone on, and 
there is still a residuum of early forms. We are led then 
to the conclusion that life in its various forms on this 
planet, now acknowledged to be the work of evolution, 
was an appendix, as it were, to the work of inorganic 
evolution carried on in a perfectly different way. 
Although the way was different, still nature is so parsi- 
monious in her methods—she never does a thing in two 
ways that can be as well done in one—that I have no 
doubt that when these matters come to be considered, as 
they are bound to be considered with the progress of our 
knowledge, we shall find a great number of parallels ; but 
I am not looking for these parallels now. What I wish 
to drive at is a chemical point of view which I think of 
some importance in relation to what has gone before ; it 
is a point which I wish to make depending upon the 
existence of those elements which make their appearance 
in the hottest stars. In inorganic forms, in those repre- 
sented to us in the hottest stars and the stars of gradually 
lower temperature, we have forms produced by a junction 
of like or unlike forms. Very good; but the more of 
these junctions the more the early forms must have dis- 
appeared, unless we’ may take it that they may have 
been made occasionally to reappear by the destruction of 
the later forms: that is a point to bear in mind. If the 
simpler forms must go on doubling to provide the more 
advanced forms, then if all the simpler forms are so used 
up there will be none left, and the only chance of getting 
the simpler forms again is to destroy something which 
had been previously made ; and we can quite understand, 
of course, that there were many conditions of this dis- 
truction possible at the time when the crust of the earth 
was being formed. But however that may be, the gaseous 
elements with the non-gaseous elements first formed, 
would be the chief chemical substances on the surface 
and over it. Now the substances over the crust, of 
course, would be the gases, oxygen, hydrogen, nitrogen, 
and from the stars we can suggest carbon combined 
withthem ; that is to say, hydrocarbons, carbonic acid, and 
NO. 1544, VOL. 60] 
so on. On the surface, whether the surface be one of land 
or water, we should expect, in addition to the low melting 
point metals lithium and sodium, those two metals which 
we know existed in the hottest stars long before the 
others, magnesium and calcium. I have told you that 
lithium probably and sodium certainly exist in some of the 
relatively hot stars ; the evidence also suggests sulphur, 
and this is rendered more probable because of the sim- 
plicity of its spectrum-series. Now these are very remark- 
able associations, and seem far away from ordinary 
chemical considerations, but they are the most important 
substances in sea water. 
Constituents of Sea Water. 
Chloride of sodium 
i 77°75 
55 magnesium 10°87 
Sulphate of “5 4°73 
a lime... 3°60 
s potash ... 2°46 
Bromide of magnesium 0°21 
Carbonate of lime ... 0°34 
The most easily thinkable evolution under these cir- 
cumstances would be that of organisms built up of these 
chemical forms, chiefly because they would represent 
the more mobile or the more plastic materials. You 
would not expect evolution to have begun in iron, 
you would have expected it to have begun in some- 
thing which was the most mobile and the most 
plastic. The available matter then for this evolu- 
tion would be those gases plus those metals and those 
non-metals to which I have referred. Now, mark this. 
Suppose you have this evolution ; if the forms so com- 
posed were to be multiplied indefinitely, the available 
material would be used up and organic evolution would 
be brought just as certainly to a dead-lock as the in- 
organic evolution was brought to a dead-lock when there 
was no possibility of any considerable reduction of 
temperature. We should expect a tendency to growth 
among the organic molecules, I dare not call it an 
inherited tendency, but I feel almost inclined to do so, 
having the growth of crystals in mind. Now, suppose 
that after you have got these new organic forms, the 
results instead of being stable were emphatically 
unstable, and still better, suppose you could induce a 
dissolution or the destruction of parts or wholes, progress 
would always continue to be possible, and indeed it might 
be accelerated.? 
The new organic molecules would ultimately not have 
the first user of the chemical forms left available by the 
inorganic evolution, but they would have the user of the 
gases and other substances produced by the dissolution 
of their predecessors. They would be shoddy chemical 
forms, it is true, but shoddy forms would be better than 
none. Under these circumstances and in this way, the 
organic kingdom would be allowed to go on ; in other 
words, the dissolution of parts or wholes of the néw 
organisms would not merely be an advantage to the race, 
but might even be an essential condition for its con- 
tinuance. 
It therefore looks very much as if we can really go 
1 My friend and colleague, Prof. Howes, has called my attention in this 
connection to Prof. Weismann’s views (‘‘ Weismann on Heredity,” vol. i. 
. 112), who seems to have arrived at somewhat similar conclusions, though 
by a vastly different road. He says, in his “ Essay on Life and Death, 
“In my opinion life became limited in its duration not because it was con- 
trary to its very nature to be unlimited, but because an unlimited persistence 
of the individual would be a luxury without a purpose.” 
The general view I have put forward, however, suggests that perhaps it 
was not so much a question of /wxrury for the living as one of necessity in 
order that others might live ; it was a case of mors anua vitae. 
The whole question turns upon the presence or absence, in all regions, ot 
an excess of the early chemical forms ready to be used up 77 a@d/ necessary 
proportions. Hence it may turn out that the difficulty was much greater 
for land- than for sea-forms, that is, that dissolution of parts or wholes of 
land-forms proceeded with the greater rapidity. It is a question of the 
possibility of continuous assimilation (see Dantec, “ La Sexualité,” p. 11), 
and the word “ parts” which I have used refers to the somatic cells, and not 
to the “‘immortal’” part of living organisms. 
