83 
tion of the land. There can be no doubt that the land round the Bay of 
Concepgion was upraised 2 or 3 feet ; at the island of St. Maria (about 30 
miles distant) the elevation was greater ; on one part Captain Fitzroy found 
beds of putrid mussel-shells still adhering to the rocks 10 feet above high- 
water mark, where the inhabitants had formerly dived at low water spring- 
tides for these shells.” 
After this testimony of “ experience }) versus “ theory/' a 
man must be a bold one who would take any upheaval theory 
as a basis for a chronometrical scale of geological ages. 
Again, we have the vast depths of certain strata, the chalk, 
for instance, formed for the most part of the skeletons of 
minute infusoria, foraminifera, diatomace83, and other crea- 
tures. These, we are told, must have taken myriads of ages 
to form. Ehrenberg estimates that there are 41,000 millions 
of the silicious skeletons of diatomaceae in one cubic inch of 
Bilin tripoli. That gives a little cube, each of its sides being 
the ten-thousandth part of an inch in size, for each of these 
remains. Some say the chalk foraminifera are smaller than 
these diatomaceae. Let us take their little cubes as one hun- 
dred-thousandth part of an inch, then we shall have 10 15 , that 
is, 1 followed by 15 ciphers, for the number packed in a 
cubical inch of chalk formed solely of their remains. Surely 
the cretaceous strata of Europe, formed by such minute crea- 
tures, must have taken myriads of ages in its formation. Let 
us test this by a little arithmetic. We will suppose one forami- 
nifera created, in one year to produce 1 0 others, each of these 
10 more the next year, each of these 10 the next year, and so 
on, multiplying tenfold each year ; at the end of any given year 
the number produced will be 10 n “ 1 , n being the number of the 
years elapsed. 
The number of cubical inches in a cubic mile lies between 
10 14 and 10 15 . Taking the larger of these two figures for con- 
venience in calculation, 10 15 multiplied by 10 15 , equalling 10 3 °, 
will give the number of foraminifera in a cubic mile. Multi- 
plying this number by 10 16 , we shall have 10 46 for the number 
of foraminifera covering an area of 100 million of square miles 
a mile in height. Hence, the foraminifera produced in the 
47 th year alone would cover more than an area of 100 million of 
square miles a mile high. Less than half a century. Now, if 
I had taken days instead of years for the probable average 
duration in which the generations of foraminifera multiply, 
and if I had taken their increase as a hundredfold instead of 
tenfold, I might not probably have erred from the facts of 
nature. But it will be objected that long before such a rate 
could be reached, food for the nourishment of the foraminifera 
g 2 
