so sickened with lectures at
Edinburgh that I did not even attend Sedgwick's eloquent and interesting
lectures." ("L.L." I. page 48.)

It was only after passing his examination, and when he went up to spend
two extra terms at Cambridge, that geology again began to attract his
attention. The reading of Sir John Herschel's "Introduction to the Study
of Natural Philosophy", and of Humboldt's "Personal Narrative", a
copy of which last had been given to him by his good friend and mentor
Henslow, roused his dormant enthusiasm for science, and awakened in his
mind a passionate desire for travel. And it was from Henslow, whom
he had accompanied in his excursions, but without imbibing any marked
taste, at that time, for botany, that the advice came to think of and to
"begin the study of geology." ("L.L." I. page 56.) This was in 1831, and
in the summer vacation of that year we find him back again at Shrewsbury
"working like a tiger" at geology and endeavouring to make a map
and section of Shropshire--work which he says was not "as easy as I
expected." ("L.L." I. page 189.) No better field for geological studies
could possibly be found than Darwin's native county.

Writing to Henslow at this time, and referring to a form of the
instrument devised by his friend, Darwin says: "I am very glad to say I
think the clinometer will answer admirably. I put all the tables in my
bedroom at every conceivable angle and direction. I will venture to say
that I have measured them as accurately as any geologist going could
do." But he adds: "I have been working at so many things that I have
not got on much with geology. I suspect the first expedition I take,
clinometer and hammer in hand, will send me back very little wiser and
a good deal more puzzled than when I started." ("L.L." I. page 189.)
Valuable aid was, however, at hand, for at this time Sedgwick, to whom
Darwin had been introduced by the ever-helpful Henslow, was making one
of his expeditions into Wales, and consented to accept the young student
as his companion during the geological tour. ("L.L." I. page 56.) We
find Darwin looking forward to this privilege with the keenest interest.
("L.L." I. page 189.)

When at the beginning of August (1831), Sedgwick arrived at his father's
house in Shrewsbury, where he spent a night, Darwin began to receive his
first and only instruction as a field-geologist. The journey they took
together led them through Llangollen, Conway, Bangor, and Capel