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PRESIDENTIAL ADDRESS. 17 
that there should be a certain quantity of hydrogen for the 
water—not too much, nor too little—as well as what was 
required for the tissues of plants and animals. Silicon and 
aluminium are necessary to form a non-conducting crust. 
Oxygen is necessary for the water, and to combine with the 
silicon and aluminium; while enough must remain over for 
the respiration of animals. Carbon must be in sufficient 
quantity in the atmosphere for the plants, but it must not 
be so abundant as to poison the animals. And calcium is 
necessary for the skeletons of animals, without which they 
could not have grown to any size. Too much lime, how- 
ever, would have taken all the carzon out of the atmosphe.e, 
and there would be none left for the plants. A little more 
hydrogen or carbon, or a little less oxygen or silicon, would 
have rendered the earth uninhabitable. Even the right 
proportion of the elementary substances would have proved 
useless if the earth had been too small, or if the temperature 
of its surface had been much hotter or colder than it 1s. The 
latter depends upon the distance and temperature of the 
sun, and has nothing to do with the size and composition of 
the earth. Also, if man was ever to become civiliced, gold, 
copper, and other metals in accessible positions were neces- 
sary, although they are of no use in the economy of animals 
and plants. Gold, however, would be almost useless to 
man if it was abundant, while iron would be equally useless 
if it was as rare as gold. But we know that these, as well 
as the other substances, exist in their right proportion. 
We cannot believe that all these various and complicated 
adjustments were brought about by a fortuitous concourse 
of meteorites. When a writer of stories wrecks his hero on 
an uninhabited island, on which, from time to time, he finds 
everything he wants to make himself comfortable, we think, 
as we read, that the story cannot be true, because all these 
useful things could not possibly have come to the island by 
chance. It is just the opposite with the story of the earth. 
In this case we know that the statements are true. We 
know that all these useful things were found when they were 
wanted. First, the silica and alumina for the earth’s crust; 
then, the carbon, nitrogen, and other materials for the pro- 
toplasm ; then, copper, iron, and gold for man. Here, also, 
we say that this cannot be due to chance, and the only 
alternative is design. 
It is possible that, in the meteoritic hypothesis, we may 
find an explanation of the relations between the size of the 
earth, its internal temperature, and its distance from the 
sun, although this is not likely, as there is no uniform grada- 
tion among the planets in these matters. But, even if the~ 
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