194 REV. A. IRVING, D.SC., B.A., ON 
greater in the inverse proportion to the squares of the distances) 
were much greater and more f:equent than the tides of the present 
ocean, as Sir Robert Ball taught us long ago. On this point I 
wrote more than twenty years ago (see Chem. and Phys. Studies, etc., 
p. 91):—* On the supposition that the ‘crust’ had sufficiently cooled 
to allow of a general condensation of water upon it, the vast 
accumulations of the materials of the Cambrian slates, grits, and 
conglomerates can be understood as resulting from the destruction, 
and deposition of sedimentary detritus from the cooled slaggy 
crust and its voleanic ejectamenta by the great tidal waves which 
swept over and levelled down the inequalities of that crust, even 
though (as some have thought*) there may have been no very 
general elevation of dry land above the ocean-waters in the 
Cambrian and Silurian periods.” Those conglomerates, etc., have of 
course partaken in the great earth-movements since, which have 
resulted in the building of the present continents and mountain 
systems; and it would be a marvel if the contained blocks did not 
here and there simulate such signs of “ glaciation” (smoothing, 
polishing, striation and scarring) as have been shown by Professor 
Albert Heim of Ziiricht to oceur in slow long-continued earth- 
movements. When these things are considered, the value of the 
evidence lately produced by Professor P. E. Coleman,{ and the 
recorded evidence of a similar nature in the Permian conglomerates 
of South Africa, India and Australia, is very largely discounted as 
evidence of gluciation. Such a notion is opposed to an over- 
whelming mass of cosmic evidence. 
VI. Lire IN GENERAL. 
In concluding his adress to this Institute$ from which I 
have quoted above, Lord Kelvin said: “Mathematics and 
dynamics fail us when we contemplate the earth fitted for life 
but lifeless, and try to imagine the commencement of life upon 
it. This certainly did not take place by any action of chemistry 
or electricity, or crystalliue grouping of molecules under the 
intluence of force, or by any possible fortuitous concourse of 
atoms. We must pause, face to face with the mystery and 
miracle of the creation of living creatures.” 
This is profoundly true. Later on (in 1903) I heard Kelvin 
emphasize this with all tie force of his great personality in his 
* See references above to the Guardian correspondence. 
+ “ Bergstiirze,” Geol. May. (March, 1883). 
{t See Nature (Nov. 17th, 1909). 
g Trans. Vict. Inst., vol. xxix ; compare Lionel Beale, F.R.S., bzd., vol. 
SEXV. 
