f the thinking faculty in this way.
To all such questions, answers which are necessarily incomplete,
though true as far as they go, may be given by any teacher whose
ideas represent real knowledge and not mere book learning: and a
panoramic view of nature, accompanied by a strong infusion of the
scientific habit of mind, may thus be placed within the reach of
every child of nine or ten."

In 1880 Huxley, in association with Professor Roscoe, the chemist, and
Professor Balfour Stewart, the physicist, took a great practical step
toward securing the widest possible extension of elementary knowledge
in science. They became general editors, for the English publishing
house of Macmillan, of a series of "Science Primers." These were
written in simple language, suitable for those with no preliminary
knowledge of science, but were the work of the chief authorities in
the leading branches of science. They were published at what was then
the phenomenally cheap price of a shilling, and they sold in almost
incredible numbers. Huxley himself wrote the introductory volume to
this great series of tracts, taking for his subject the simplest and
most natural phenomena of the world and the simplest chains of cause
and effect that can be observed around us. The keynote of the little
book was that knowledge of nature could be gained only by observation
and experiment, and that for these the ordinary things in the world
around us provided ample material. A few years later he wrote a more
advanced volume on the same subject. He had now found an English name
for the German _Erdkunde_, and his book on _Physiography_ was simply
an account of the leading things and forces of nature. A traveller
set down in a foreign land will at once get into difficulties unless
he has provided himself with a guide to the geography, the manners and
customs, and the regulations of the country in which he finds himself.
Huxley's aim was to provide a similar guide to nature; an outline of
elementary knowledge of the world into which we all come as strangers.
He wrote of force and energy, of the forms of water, of heat and cold,
of the atmosphere, of winds and tides and weather, and of the main
features of the lives of plants and animals. There was nothing new in
what he wrote; he simply took from the chief sciences their leading
principles and elementary facts, and set them forth in plain and
simple language so that all could read and u