Preface.

THOUGH not professing to be a Manual of the Sciences -a thing impossible within the limits of a single volume this Work is yet so arranged as to present the leading features of a connected compendium. The object of the Compiler has been at once to instruct and attract;-to instruct by facts drawn from the most direct and authentic sources; and to attract by presenting these facts in the most intelligible language at command. There is nothing given in these pages beyond the comprehension of an advanced pupil of average ability; and where technicalities appear they are explained as they occur, that there may be no interruption to the sequence, nor imperfect understanding of the information intended to be conveyed. In this respect, indeed, the volume may be regarded as fitted alike for the general reader and the schoolboy; an instructive companion for the leisure hour of the one, and a necessary text-book for the training of the other.

November 1868.

"The study of the Natural Sciences, as a means of Education, is a necessity of our age. Along with the all-important instructions in the fundamental principles of morality and religion, Education should unfold and exercise the different mental faculties, and store the mind with a certain amount of general useful knowledge."-LIEBIG'S Familiar Letters on Chemistry.