PREFACE. 
* The Geologist,' at whicli I have laboured witli assiduity and 
pleasure for more than six years, is brought unexpectedly to a close, 
with only half the quantity of matter usually devoted to a volume. 
A new geological magazine is announced, and havhig received an 
intimation from my publishers that to continue ' The Geologist ' in 
rivalry with it would be attended with anxiety, and perhaps with 
loss, I have decided to retire from the field rather than take part in 
a contest that might prove injurious to both. 
To give up tliis monthly intercourse with so many friends at home 
and abroad is, naturally enough, a source of regret to me, if not ot* 
pain. I labour, however, neither to gratify vanity nor for gain. The 
honest wish of spreading and advancing knowledge, and of giving 
free scope to the expression of geological theories and criticism, has 
been my motive for maintaining this periodical, and I may with truth 
assert that, during the period of its publication, it has been a means 
of free intercourse among all classes of geologists. To its pages it 
has been my pride that all should, fairly and freely, have admission. 
My duties are done; and in for ever closing this work I will but 
add, tliat had there been any option left with me I should have pre- 
ferred to have completed this volume in full to the end of the year. 
There are, however, stronger reasons than I can control for closing 
it at once. With all my numerous friends I beg, however, to re- 
main in personal correspondence ; while the new works I hope to 
project will soon put me again in open communication with the 
world, and w ill, 1 trust, prove not merely my desire but my capacity 
