T.H. HUXLEY.

HODESLEA, EASTBOURNE,

_April, 1894._

CONTENTS

I

ON A PIECE OF CHALK [1868]
(A Lecture delivered to the working men of Norwich during the meeting of
the British Association.)

II

THE PROBLEMS OF THE DEEP SEA [1878]

III

ON SOME OF THE RESULTS OF THE EXPEDITION OF H.M.S. "CHALLENGER" [1875]

IV

YEAST [1871]

V

ON THE FORMATION OF COAL [1870]
(A Lecture delivered at the Philosophical Institute, Bradford.)

VI

ON THE BORDER TERRITORY BETWEEN THE ANIMAL AND THE VEGETABLE KINGDOMS
[1876]
(A Friday evening Lecture delivered at the Royal Institution.)

VII

A LOBSTER; OR, THE STUDY OF ZOOLOGY [1861]
(A Lecture delivered at the South Kensington Museum.)

VIII

BIOGENESIS AND ABIOGENESIS [1870]
(The Presidential Address to the Meeting of the British Association for
the Advancement of Science at Liverpool.)

IX

GEOLOGICAL CONTEMPORANEITY AND PERSISTENT TYPES OF LIFE [1862]
(Address to the Geological Society on behalf of the President by one of
the Secretaries.)

X

GEOLOGICAL REFORM [1869]
(Presidential Address to the Geological Society.)

XI

PALAEONTOLOGY AND THE DOCTRINE OF EVOLUTION [1870]
(Presidential Address to the Geological Society.)

I

ON A PIECE OF CHALK

[1868]

If a well were sunk at our feet in the midst of the city of Norwich, the
diggers would very soon find themselves at work in that white substance
almost too soft to be called rock, with which we are all familiar as
"chalk."

Not only here, but over the whole county of Norfolk, the well-sinker
might carry his shaft down many hundred feet without coming to the end of
the chalk; and, on the sea-coast, where the waves have pared away the
face of the land which breasts them, the scarped faces of the high cliffs
are often wholly formed of the same material. Northward, the chalk may be
followed as far as Yorkshire; on the south coast it appears abruptly in
the picturesque western bays of Dorset, and breaks into the Needles of
the Isle of Wight; while on the shores of Kent it supplies that long line
of white cliffs to which England owes her name of Albion.

Were the thin soil which covers it all washed away, a curved band of
white chalk, here broader, and there narrower, might be followed
diagonally across England from Lulworth in Dorset, to Flamborough Head in
Yorkshire--a distance of over 280 miles as the crow flies. From this band
to the North Sea, on the eas