medicine, he settled down in
London. He married happily and shared in the common joys and sorrows
of domestic life. Advancement came to him steadily, and, although he
was never rich, after the first few years of life in London, his
income was always adequate to his moderate needs. For the greater part
of his working life, he lived actually in London, in the ordinary
style and with the ordinary social enjoyments of a professional man.
His duties in connection with the Royal College of Science and with
the Geological Survey were not arduous but constant; his time was
fully occupied with these, with his scientific and literary work, with
the business of scientific societies, with the occasional obligations
of royal commissions, public boards, and lecturing engagements. The
quiet routine of his life was diversified by many visits to provincial
towns to deliver lectures or addresses, by meetings of the British
Association, by holidays in Switzerland, during which, with Tyndall,
he made special studies of the phenomena of glaciation, and in the
usual Continental resorts, and by several trips to America.

In a rough-and-ready fashion, Huxley's active life may be broken into
a set of decennial periods, each with tolerably distinctive
characters. The first period, roughly from 1850 to 1860, was almost
purely scientific. It was occupied by his voyage, by his transition to
science as a career, his researches into the invertebrate forms of
life, the beginning of his palaeontological investigations, and a
comparatively small amount of lecturing and literary work. The second
decennium still found him employed chiefly in research, vertebrate and
extinct forms absorbing most of his attention. He was occupied
actively with teaching, but the dominant feature of the decennium was
his assumption of the Darwinian doctrines. In connection with these
latter, his literary and lecturing work increased greatly, and the
side issues of what was, in itself, purely a scientific controversy
began to lead him into metaphysical and religious studies. The third
period, from 1870 to 1880, was considerably different in character. He
had become the most prominent man in biological science in England, at
a time when biological science was attracting a quite unusual amount
of scientific and public attention. Public honours and public duties,
some of them scientific, others general, began to crowd upon him, and
the time at his disposal for the quiet labours o