from the auther 161

AUTHOR OF “CONVERSATIONS ON CHEMISTRY,”

NATURAL PHILOSOPHY," ETC. ETC.

Scbenth Edition,

REVISED AND ENLARGED.

LONDON:

PRINTED FOR

LONGMAN, ORME, BROWN, GREEN, & LONGMANS

PATERNOSTER-ROW.

1839.

HB 161 M 314

18.31

LONDON: Printed by A. SPOTTISWOODE,

New-Street-Square.

HP

IEL ,N314 1839

PREFACE.

In offering to the Public this small work, in which it is attempted to bring within the reach of young persons a science which no English writer has yet presented in an easy and familiar form, the author is far from inferring, from the unexpected success of a former elementary work, on the subject of Chemistry, that the present attempt is likely to be received with equal favour. Political Economy, though so immediately connected with the happiness and improvement of mankind, and the object of so much controversy and speculation among men of knowledge, is not yet become a popular science, and is not generally considered as a study essential to early education. This work, therefore, independently of all its defects, will have to contend against the novelty of the pursuit with young persons of either sex, for the instruction of whom it is especially intended. If, however, it should be