A New Edition,

WITH ADDITIONS AND IMPROVEMENTS.



LONDON:

DARTON AND CLARK, HOLBORN HILL.

Entered at Stationers' Hall.

TO

GEORGE BIRKBECK, Esq. M.D., F.G.S.,

PRESIDENT OF THE LONDON MECHANICS' INSTITUTION,

AS A TRIBUTE OF RESPECT

FOR


HIS BENEVOLENT AND EFFECTUAL ENDEAVOURS TO PROMOTE THE
DIFFUSION OF KNOWLEDGE,

This Little Work

IS,

WITH PERMISSION, DEDICATED

BY THE EDITOR.

« iv »
« v »