242 Nature Study. [Sess. 
for a generation they had never noticed the ice-markings. 
Examples might be multiplied indefinitely. When the British 
Association was in Edinburgh last, I heard the late Professor 
Fitzgerald make some remarks which were so pithy that I have 
not forgotten them yet. He said that the study of Greek 
literature had made very little impression on us as a nation, 
because the thoughts were conveyed in an almost unknown 
language; while Hebrew literature had had an enormous in- 
fluence on us, because the Bible had been translated into 
the vernacular. Nature study is the vernacular of the race, 
by the use of which it has made all its great discoveries ; 
and when we prefer secondhand knowledge to nature study, 
we allow our powers of observation to become atrophied. 
We are much more impressed by observations made by 
ourselves than things we read about. The fact observed is 
like a scene in the sunlight; the other is like a photograph 
which, however accurate, wants life and colour. Let me give © 
an illustration or two from my own experience. Many years 
ago I visited Yellowstone Park, and amidst the many wonders” 
of that region of geysers was one which made a great impres- 
sion on me. It was to see the water in the geyser basins of a 
beautiful blue-green colour, from the living alge it contained. 
The water was boiling—that is, it had a temperature of about 
180° Fahr., which is the boiling-point at the elevation where 
we were. I could not believe that it was possible for proto- 
plasm to live at that temperature, and my first impulse was to 
doubt that these delicate organisms were alive at all. Many 
years after, at a meeting of the Royal Society, I was delighted 
to hear Lord Kelvin express his wonder at finding similar 
organisms in the hot springs of Banff, in Canada. His in- 
ference was that living alge might exist on the earth when ib 
was much hotter than it is, and supply the atmosphere with 
oxygen. Later, I found other cases of simple organisms living 
in most unexpected places,—for example, a mould growing in 
dilute sulphuric acid; from which it may be concluded that 
the physical basis of life has powers of adapting itself to con- 
ditions as yet not dreamt of in our philosophy. 
But Yellowstone is in a far country, and not many of us 
wander thither. Let me take another illustration of the — 
impressiveness of seeing things for oneself, and this from ow ; 
