Geology Reference
In-Depth Information
which sediments had been derived and then estimate the time
it had taken to deposit the new sediments.
'Situated as I am in
Africa without any geological literature,'
he wrote,
'I can only
give the most approximate estimates'
. But he did not let that
stop him! Taking his new approach to estimating rates of sedi-
mentation, he calculated that it had taken 325 million years to
deposit all the sediments that had accumulated since the Base
Cambrian. He was thus comforted to find that this was a value
much closer to the radiometric estimate of around 500 million
years for the Base Cambrian, and felt relieved that radiometric
ages were not as unreasonable as some geologists believed. In
fact, because there really was no way of estimating the vast quan-
tities of rock that had once been deposited but had since been
eroded away over countless geological eras, this way of calcu-
lating the amount of sediments that had been deposited since
the Base Cambrian was no more meaningful than any of the
other hour-glass methods around, but the improved age agree-
ment probably made him feel better.
He wrote a short article on his results and wrote to Bob ask-
ing him to see to its publication:
I want you to do me a favour which I am sure you will be
glad to do. Read over the article and if you find it without fal-
lacy, I should like you to verify my figures. Your correspon-
dence with Dr. Jude is highly complimentary to you and is
great evidence of the height to which you must have climbed
mathematically. In that direction I feel absolutely ignorant -
even though I know probably far more than the average geo-
logical man.
Another dig at the innumerate geologist!
Having sent my letter to 'Nature' keep your eye on the sub-
sequent numbers and if it should be published get three
copies. For the expense of the above 2/6 will probably suffice
and I will tell mother to give it you.
He did not receive a reply from Bob confirming his acquies-
cence to this request until three months later, by which time it
