Darwin, would never have been written.

At length, however, after much preparation and many delays, the
_Beagle_ sailed from Plymouth on December 27th, 1831, and five years
elapsed before Darwin set foot again on English soil. The period,
therefore, in Darwin's life which we find covered by his term at
Edinburgh and Cambridge, until at the age of 22 he found himself
suddenly launched on an entirely new experience full of adventure and
fresh association, was spent by Wallace in a somewhat similar manner in
so far as his outward objective in life was more or less distinct from
the pursuits which gradually dawned upon his horizon, though they were
followed as a "thing apart" and not as an ultimate end.

With Wallace's removal into Bedfordshire an entirely new life opened up
before him. His health, never very good, rapidly improved; both brain
and eye were trained to practical observations which proved eminently
valuable. His descriptions of the people with whom he came in contact
during these years of country life reveal the quiet toleration of the
faults and foibles of others, not devoid of the keen sense of humour and
justice which characterised his lifelong attitude towards his
fellow-men.

The many interests of his new life, together with the use of a pocket
sextant, prompted him to make various experiments for himself. The only
sources from which he could obtain helpful information, however, were
some cheap elementary books on mechanics and optics which he procured
from the Society for the Diffusion of Useful Knowledge; these he studied
and "puzzled over" for several years. "Having no friends of my own age,"
he wrote, "I occupied myself with various pursuits in which I had begun
to take an interest. Having learnt the use of the sextant in surveying,
and my brother having a book on Nautical Astronomy, I practised a few of
the simpler observations. Among these were determining the meridian by
equal altitudes of the sun, and also by the pole-star at its upper or
lower culmination; finding the latitude by the meridian altitude of the
sun, or of some of the principal stars; and making a rude sundial by
erecting a gnomon towards the pole. For these simple calculations I had
Hannay and Dietrichsen's Almanac, a copious publication which gave all
the important data in the Nautical Almanac, besides much other
interesting matter useful for the astronomical amateur or the ordinary
navigator. I also tried to make a telescope b