316 PRACTICAL AND SCIENTIFIC ZOOLOGY. 
mals of the country they go through, and come under the 
denomination of practical naturalists, find that the 
preservation of specimens is absolutely necessary, and 
for the same reasons. It is obvious, however, that the 
principle upon which, in these cases, they should pro- 
ceed, is very different from that already suggested for 
the adoption of the scientific naturalist. There is no 
occasion to preserve objects to which they can attach no 
anecdote or history, unless they collect for the ulterior 
purposes of general science. In either case, however, 
every naturalist and traveller would do well to make 
himself acquainted with the ordinary process of pre- 
serving skins, and of collecting and preserving insects 
and shells. As for the soft mollusca, very little inform- 
ation can be obtained from them, after they have been 
contracted by being put into spirits. 
(381.) Technical words will prove, at first, a great hin- 
derance to the student ; but they are inevitable. They 
constitute, in fact, the language of zoology, since they 
are employed to express ideas which cannot be conveyed 
by words in ordinary use. To lessen this difficulty, we 
shall arrange all the words of this description, as they 
occur, at the end of each succeeding volume, where they 
may be immediately referred to. Such as are of fre- 
quent occurrence had better be copied out in a memo- 
ryandum book for more perfect recollection ; a plan 
which would tend more to fix them upon the memory 
than any other we could recommend. 
(382.) The assistance of books is as important as the 
assistance derived from specimens: by the latter we 
study nature, while by the former we learn the opi- 
nions of her expounders, and the progress they have 
made in recording her manifold works. Let us re- 
member that the latter are Divine, while the former 
partake more or less of that imperfection which belongs 
to every thing human. 
