betwixt it and all other facts is exhibited. The student thus acquires by degrees the faculty of comparing, reasoning, and judging correctly; the acquisition and proper development of which is the chief end of mental culture. I trust that I have, in some measure, succeeded in compiling a Treatise exhibiting, in a mathematical form, but without mathematical technicalities and symbols, the various process by which the establishment of any proposition in Physics is arrived at, and the nature of the evidence which enables us to speak with confidence of the truth of any theory; exhibiting also, what may be considered as certain, what only probable, what absolutely unknown. The sphere of our knowledge being thus defined, we shall have made some progress towards ascertaining the limits of human faculties. I am aware that, in the preceding remarks, I have described what the following work ought to be, rather than what it is; but still I trust that it will be found useful for the purposes of general education; and that by the removal of some unnecessary obstacles, the student's progress to many of the higher departments of science will be facilitated. At all events, this attempt may perhaps stimulate others better qualified for the task to devote their talents to the preparation of similar works. To make any proper acknowledgment of the many various sources from which I have derived assistance in the compilation of the present work, would be impossible; but I must express my deep obligations to the Élémens de Physique of Pouillet; from which valuable work I have borrowed much. The reader is referred to the annexed copious Table of Contents for the various subjects treated of in the following pages. London, Aug. 1837. T. W. CONTENTS. CHAP. I.-INTRODUCTORY OBSERVATIONS... p. r Introduction—Laws of Nature-Physical Theory-Space and Time— CHAP. II-THE PROPERTIES OF BODIES Arts. 1-6 p. 13 Divisibility—Atomic Theory- Compressibility-Porosity - Elasticity Arts. 7-12 CHAP. III. THE PROPERTIES OF SOLIDS AND CRYSTALLO- GRAPHY - p. 20 Hardness, &c.- Friction- Crystallization — Primitive and Secondary CHAP. IV.-LAWS OF EQUILIBRIUM AND OF MOTION Arts. 13-17 Equilibrium Action and Reaction - Resultants- Parallelogram of CHAP. V.-ON GRAVITY .... p. 51 SECTION I Weight Direction of Gravity-Laws of Falling Bodies—Uniformly SECTION II. The Pendulum-Laws of the Cycloidal Pendulum-Simple Pendulum CHAP. VI.-ON THE LAWS OF FLUIDS. SECTION I. p. 90 General Properties of Fluids-Compressibility-Equal Transmission Arts. 66-81 SECTION II. Floating Bodies-Loss of Weight-Conditions of Equilibrium-Spe- Arts. 82-87 SECTION III. Laws of Elastic Fluids-Elastic Force-Illustrations-Dalton's Laws Arts. 88-91 SECTION IV. Existence of an Atmosphere-Pressure of the Atmosphere-Levelling .... Arts. 92-101 SECTION V. Laws of Fluids in Motion-Velocity of Efflux-Vena Contracta-Ad- Arts. 102-110 |