proved to be wrong, and a book is much harder to sweep under
the carpet than a single paper. He decided to write to his friend
Reginald Daly in America.
Although a much older man, Daly, like Holmes, had a back-
ground in physics. The two men were also both passionate
about igneous rocks, Daly recalling that his interest in geology
stemmed from the moment Professor A. P. Coleman held up a
piece of granite and remarked, 'This is made of crystals'. Daly
had long been an admirer of Holmes and had organised his lec-
ture tour of the States in 1932, whereupon the two men had
become close friends and since then had regularly corre-
sponded. It also transpired that Daly too had lost a child at the
age of three, his only child as it turned out. So, as he was one
of the few Americans who had openly converted to the theory
of continental drift, it was natural that Holmes should write to
him expressing a moment of doubt:
I have been hesitating whether or not to put continental drift
into the topic. On the whole, I think not. I am still doubtful
about it . . . We really need a first class palaeontologist to
assess the biological evidence at its true value. If you could
stimulate someone to do that and then take up the problem
in the sane light of your long experience we might expect some
real progress. However, while it may be complimentary, it is
hardly kind to thrust upon you all the headaches and night-
mares that such an enterprise would entail!
Daly did not take up the challenge.
In the end Holmes decided that he could hardly ignore what
he had been preaching for so long and what, in his heart of
hearts, he really considered to be the truth. He had been teach-
ing his students about continental drift for nearly twenty years.
Consequently, when they went to conferences at other universi-
ties where the old ideas of land bridges and ismuths (island
'stepping stones') were still advocated, they were amazed to dis-
cover that what they understood to be the accepted doctrine
turned out to be considered heretical and revolutionary.