271 
of Edinburgh^ Session 1864-65. 
certain evidence that this gradation has been the gradation of a 
rising scale — of progressive creations from lower to higher types. 
But this dispute is maintained only on the ground, that we cannot 
safely trust to negative evidence. It is an unquestionable fact, that 
so far as this kind of evidence can go, it does testify to the suc- 
cessive introduction of higher and higher forms of Life. Very 
recently, a discovery has been made, to which Mr Darwin only a few 
years ago referred, as ‘‘ a discovery of which the chance is very 
small,” viz., of fossil organisms in beds far beneath the lowest 
Silurian strata. This discovery has been made in Canada — in 
beds far down, near the bottom even, of the rocks hitherto termed 
“ Azoic.” But what are the forms of life which have been found 
here ? They belong to the very lowest of living types, — to the 
“ Ehizopods.” So far as this discovery goes, therefore, it is in 
strict accordance with all the facts previously known, — that as we 
go back in time, we lose, one after another, the higher and more 
complex organisms, — first, the Mammalia; then, the Vertebrata; 
and now lastly, even the Mollusca. It is in accordance, too, with 
another fact which has been observed before, viz., that particular 
forms of life have attained, at particular epochs, a maximum de- 
velopment both in respect to size and distribution, — the favourites 
as it were, of Creation for a time. These earliest Ehizopods seem 
to have been of enormous size and developed on an enormous scale, 
since there is good reason to believe that beds of immense thick- 
ness are composed of their remains. All that is new in this dis- 
covery is the vast extension which it gives in time to the same rules 
which had been already traced through ages which we cannot num- 
ber. The facts of creation, therefore, do range themselves in an 
observed order, and in this sense, at least, it may be said with truth 
that creation has been “ by Law.” 
And now we advance one step farther. Every observed order in 
physical phenomena does suggest irresistibly to the mind the 
operation of some physical cause — the working of some force or 
forces, of which nothing more may be known than these their 
visible eff“ects. This is the second of the four senses in which I 
have said that “ Law ” is frequently used. We say of an observed 
order of facts that it must be due to some “ Law,” meaning simply 
that all order involves the idea of some arranging cause, the work- 
2 N 
VOL. V. 
