iv PREFACE. 
number of our readers, that we have in this Third Volume brought 
to aconclusion most of our Introductions to the different branches 
of Natural History, originally intended to be continued through 
several volumes. In every other respect we have adhered to our 
prospectus ; and we hope to go on in the same course for many 
years to come, gathering strength as we proceed ; and so rooting 
this periodical into the literature of the country, as that there 
must always in future be in these islands a Magazine of Natural 
History. 
With the present Volume is given a Glossarial Index to the 
technical terms made use of from the commencement of the work 
up to the present time, with references to the pages where will 
be found their explanations at length, and their application to the 
different departments of natural science. As the first step to- 
wards the knowledge of the nature of things, and to the commu-~ 
nication of that knowledge to others, is to know their names ; so 
we would earnestly recommend to our young readers, or generally 
to all those who feel that they are not yet beyond the age of 
acquiring new ideas, to study this Glossary word by word. We 
would recommend them to turn to every page referred to, so as 
not only completely to understand the word and its application, 
but to impress on the understanding and the memory the subject: 
in the discussion of which the application is made. This will be 
to master a part of every branch of Natural History, and to make 
the Magazine, as far as it has hitherto proceeded, the reader's 
own, ‘The ideas communicated to the world in this Magazine 
proceed from the minds of some hundreds of individuals, all 
directed to the same subject; they are, therefore, much more 
worthy of being fixed in the memory than those of any one 
individual; for example, in a single treatise. This is a proposition 
which will bear discussion at length; but we must leave it for 
the present, and conclude by hinting that those who peruse a 
scientific magazine, as they would glance over a merely literary 
periodical, are spending their time to very little purpose. 
J.C. L, 
Bayswater, Oct. 18, 1830. 
