MECHANICAL PHILOSOPHY, 34426 HOROLOGY, AND ASTRONOMY; BEING AN EXPOSITION OF THE PROPERTIES OF MATTER AND OF THEIR MODE OF ACTION; THE CONSTRUCTION OF INSTRUMENTS FOR THE THE HEAVENLY BODIES. enjamin illiam BY W. B. CARPENTER, M.D., F.R.S., AUTHOR OF "GENERAL AND COMPARATIVE PHYSIOLOGY," LECTURER ON NATURAL HISTORY AND COMPARATIVE ANATOMY AT ST. THOMAS'S HOSPITAL. LONDON: WM. S. ORR AND Co., PATERNOSTER ROW. MDCCCXLIV. PREFATORY NOTICE. THE following little Work is intended to occupy a place somewhat intermediate between the simpler elementary treatises on Physical science, and the more elaborate works of a professedly philosophical character. With the former, it has this in common-that the Author has aimed at adapting it to those who have no preliminary knowledge of the subject; and to carry on his readers, step by step, from the known to the unknown, without requiring from them more than an accurate acquaintance with the ground over which they have already passed. To the latter, the Author ventures to hope it may be compared in this that the highest principles of the science are introduced, and exhibited in their connexion with each other, and with the phenomena they govern. He has thus endeavoured to give his little work the character of a philosophical treatise; whilst, by the number of examples and illustrations which he has introduced, he has aimed at preventing what might have otherwise been its dry and abstruse appearance. In this attempt, he has merely followed out the plan which has proved successful in the former volume of the present Series. The only preliminary knowledge required for the comprehension of the whole of this treatise, is an acquaintance with ordinary Arithmetic, and with the rudiments of Geometry. The mere |