distribution of subjects, a logical development of scientific principles, and a remarkable clearness of definition and explanation. In addition, it is profusely illustrated with beautifully executed engravings, admirably calculated to convey to the mind of the student a clear conception of the principles unfolded. Their completeness and accuracy are such as to enable the teacher to dispense with much of the apparatus usually employed in teaching the elements of Physical Science. In preparing an American edition of this work on POPULAR PHYSICS, it has not been the aim of the editor to produce a strict translation. No effort, however, has been spared to preserve throughout, the spirit and method of the original work. No changes have been made, except such as have seemed calculated to harmonize it with the system of instruction pursued in the schools of our country. By a special arrangement with M. GANOT, the American publishers are enabled to present fac-simile copies of all the original engravings. NEW YORK, June 1st, 1860. NOTE. At the request of many teachers, a chapter has been prepared on the Application of Physical Principles to Machines. NEW YORK, June, 1861. CONTENTS. POPULAR PHYSICS. INTRODUCTION. CLASSIFICATION OF THE SCIENCES. SCIENCE is a knowledge of the laws that govern the Universe. A Law is a necessary relation between cause and effect. It is assumed as the foundation of all Science, that like causes produce like effects. This principle is an inductive truth, founded upon universal experience. By the UNIVERSE we mean all that has been created, whether material or immaterial. The Universe may be regarded as made up of mind and matter. MIND is that which thinks and wills; MATTER is that of which we become cognizant through the medium of the senses. Science admits of two corresponding divisions, Science of Mind, or METAPHYSICS, and Science of Matter, or Natural Phi LOSOPHY. NATURAL PHILOSOPHY is that branch of science which treats of the laws that govern the material Universe. Matter exists in two states, organized and unorganized; it is organized when its particles are aggregated into organs adapted to the support of life; in all other cases it is un What is Science? What is a Law? Define the Universe. Mind. Matter. What are the two divisions of Science? What is Natural Philosophy? In what two states may Matter exist? Illustrate. organized. Natural Philosophy admits of two corresponding divisions: Science of Organized Matter, or PHYSIOLOGY, and Science of Unorganized Matter, or GENERAL PHYSICS. Physiology, which treats of the laws of matter as modified by the principle of vitality, is divided into two principal branches: Animal Physiology, or ZoöLOGY, and Vegetable Physiology, or BOTANY. Both of these branches, with their various subdivisions, belong to the domain of NATURAL HISTORY. All unorganized matter may be divided into two classes, Celestial and Terrestrial. General Physics admits of two corresponding divisions. That branch which treats of celestial bodies, including the earth as a whole, is called AsTRONOMY; that which treats of terrestrial bodies, is called TERRESTRIAL PHYSICS. TERRESTRIAL PHYSICS is again subdivided into two branches. The first is called Physics Proper, or simply PHYSICS; it treats of the general properties of bodies. The second is called CHEMISTRY; it treats of the nature of the ultimate particles of bodies and of their laws of combination. The first of these branches, or PHYSICS, is the subject treated of in the following pages. Besides the branches above enumerated, and which may be called Pure Sciences, there are others that depend upon, or are applications of, two or more of them. Such, for example, are the sciences of GEOLOGY, MINERALOGY, PHYSICAL GEOGRAPHY, &c. These are called Mixed Sciences. Into what may Natural Philosophy be divided? What is Physiology, and what are its branches? How may Unorganized Matter be divided? What are the corresponding divisions of General Physics? Define them. How is Terrestrial Physics divided? What is Physics Proper? Chemistry? What are the Pure Sciences, and what are some of the Mixed Sciences? |