Science for the School and Family, Part I. Natural Philosophy

270. =Heat and Cold.=--In common language we speak of heat and cold as two distinct and opposite things. That this is not strictly correct may be shown by the following experime...

180. =Universality of Motion.=--The world is full of motion. The rising and setting of the sun, the changes of the seasons, the falling of the rain, the running of rivers into t...

334. =Nature of Light.=--We do not know what light is. There are two suppositions in regard to it. One is that of Sir Isaac Newton, called the theory of _emission_. According to...

146. =What Pneumatics Teaches.=--As Hydrostatics treats of the pressure and equilibrium of liquids, Pneumatics treats of the same in air and the gases, or aeriform substances. T...

110. =What Hydrostatics Teaches.=--Hydrostatics is that branch of Natural Philosophy which treats of the pressure and equilibrium of liquids. The phenomena which it brings to vi...

370. =Origin of the Term.=--The ancients observed that when certain substances were rubbed together singular phenomena were produced. One of these substances was amber, and as t...

222. =Machines not Sources of Power.=--The Mechanical Powers, as they are termed, are six in number--viz., the Lever, the Wheel and Axle, the Inclined Plane, the Screw, and the...

73. =Attraction Between Masses.=--I have thus far treated of attraction as existing between the atoms or particles of matter when they are brought very near together, which is c...

248. =What Sound is.=--Sound is such a vibration of substances as can, on being transmitted to the ear, act upon the sense of hearing. I say _such_ a vibration, because there ma...

17. =Variety in the Properties of Matter.=--All matter has properties or qualities. Some of these are different in the different kinds of matter. Thus its three forms have diffe...

53. =Nature of Attraction.=--If you attempt to break a very tenacious solid substance, why do you not succeed? It is because the particles are so strongly fastened together. But...

397. =Loadstones.=--It was discovered many centuries ago that a certain ore of iron has the property of attracting pieces of common iron or of steel. The fact was probably consi...

95. =Centre of Gravity Illustrated.=--If you balance a ruler on your finger, as in Fig. 30, it is balanced because there is just as much weight on one side as on the other. Now...

309. What is said of the attraction of magnetism? What law is there in regard to it? What is said of the poles of a magnet? What of magnetism by induction?

134. =Nature of the Subject.=--We now come to a very interesting subject, which is at least intimately connected with Hydrostatics, if it may not be considered a part of it. The...

Entered, according to Act of Congress, in the year one thousand eight hundred and sixty-three, by HARPER & BROTHERS, in the Clerk's Office of the District Court of the Southern...

1. =Matter and Spirit.=--The distinction between matter and spirit is almost universally recognized even by those who have given little thought to such subjects. It is a distinc...

44. =Extension.=--You can not conceive of any portion of matter, however small it may be, that has not shape or figure. It may be so small as to appear only as a point to the na...

208. What other facts sustain this inference? How did Sir Humphrey Davy prove that there is heat in ice? What are the two theories of heat? What is the chief source of heat for...

136. Give the comparisons to the operation of a spring, of firing of a cannon, and the throwing of stones from the crater of a volcano. What is said of the jumping of a man from...

258. What is Newton's theory of light? What is the undulatory theory? State the analogies to sound and heat. When is a body luminous? What are the sources of light?

112. How is the height of the atmosphere ascertained? At what rate does the earth move round the sun? How does it carry along the air with it? State the influence which gravitat...

194. What is sound? What relation has sound to rapidity of vibration? Mention cases in which the vibration of sounding bodies is manifest to the sight and touch. What is said of...

288. What is the supposed explanation of electrical repulsion? Explain the difference between resinous and vitreous electricity. What is said of the two supposed electrical flui...

175. Explain the terms power, weight, and fulcrum. What is said of the use of the lever? What is the lever of the first kind? What is said of its force?

54. What is said of the universality of attraction? Explain the tides. What is said of the attraction of the moon for the land? What is the difference between the attraction of...

20. What is said of gold-leaf, and of the wire of gold-lace? What of the soap-bubble? What of the thread of the silk-worm, and of the web of the spider? What of solution of blue...

80. What is said of the phenomena treated of in Hydrostatics? What are the two characteristics of liquids? What makes a liquid have a level surface? Give the explanation. Give t...

39. What is said of attraction in solids? What of its different modes of action? What is the difference in attraction in the case of steel and of water? What is said of the free...

74. What is said of the stability of bodies whose shapes are represented in Figs. 48, 49, and 50? What of that of a round ball? Why is the pyramid the firmest of all structures?

14. What is the origin of the word spirit? What is the relation of the senses to the spirit? What is said of the effects of matter on the senses? What are the forms of matter?

101. What is the most obvious way of ascertaining the specific gravities of different liquids? Explain the sinking of heavy substances in water. Explain the rising of light subs...

36. What is the property of matter called inertia? Give illustrations of it. Illustrate the fact that matter has no power to stop its own motion. What is the reason that the pop...

=The Child's Book of Nature.= For the Use of Families and Schools; intended to aid Mothers and Teachers in training Children in the Observation of Nature. In three Parts. Illust...