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 by purchasing a lens of
about 2 ft. focus at an optician's in Swansea, fixing it in a paper tube
and using the eye-piece of a small opera-glass. With it I was able to
observe the moon and Jupiter's satellites, and some of the larger
star-clusters; but, of course, very imperfectly. Yet it served to
increase my interest in astronomy, and to induce me to study with some
care the various methods of construction of the more important
astronomical instruments; and it also led me throughout my life to be
deeply interested in the grand onward march of astronomical
discovery.
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