The Reason Why. Robert Kemp Philp

of a candle, why is there a spark generally at the end of it, 256

       Will-o'-the-wisp, what is it, 318

       Winds, what is the cause of, 234

       Winds, why are east usually dry, 384

       Winds, why are west usually wet, 385

       Winds, why are north usually cold and dry, 386

       LESSON LXXVIII.

       Winds, why are south warm and rainy, 387

       Wind, what is it, 666

       Winds, what are the velocities of, 667

       Winds, what are trade, 668

       Winds, what is the cause of trade, 669

       Winds, why do trade winds blow from east to west, 670

       Winds, what determines the character of, 674

       Wind-mills, why do their wings turn round, 690

       Windows, why do they reflect the sun's rays in the evening, 523

       Windows, why do they not reflect the sun's rays at noon, 524

       Wood, why does decayed look luminous, 95

       Wood, burning at one end, why does it not feel hot at the other, 118

       Wood, why is it a bad conductor of heat, 119

       Wood that is green, why does it hiss and steam when burning, 285

       Wood, why does it ignite less readily than paper, 297

       Woodcocks and snipes, why have they nerves running down to the tip of their bills, 1043

       Woodpeckers, why do they "tap" at old trees, 1066

       Woollens, why are they worn in winter, 166

       Wool, what is it, 1201

       Yawn, why do we, 1026

       Zoological geography, 1326

      "God looked down from heaven upon the children of men, to see if there were any that did understand that did see God."—Psalm liii.

THE REASON WHY.

       Table of Contents

CHAPTER I.

       Table of Contents

      1. Why should we seek knowledge?

      Because it assists us to comprehend the goodness and power of God.

      And it gives us power over the circumstances and associations by which we are surrounded: the proper exercise of this power will greatly promote our happiness.

2. Why does the possession of knowledge enable us to exercise power over surrounding circumstances?

      Knowledge enables us to understand that, in order to live healthily, we require to breathe fresh and pure air. It also tells us that animal and vegetable substances, undergoing decay, poison the air, though we may not be able to see, or to smell, or otherwise discover the existence of such poison. Knowing this, we become careful to remove from our presence all such matters as would tend to corrupt the atmosphere. This is only one of the countless instances in which knowledge gives us power over surrounding circumstances.

3. Name some other instances in which knowledge gives us power.

      Knowledge of Geography and of Navigation enables the mariner to guide his ship across the trackless deep, and to reach the sought-for port, though he had never before been on its shores.

      Knowledge of Chemistry enables us to separate or to combine the various substances found in nature. Thus we obtain useful and precious metals from what at first appeared to be useless stones; transparent glass from pebbles, through which no light could pass; soap from oily substances; and gas from solid bodies.

      "Give instruction to a wise man, and he will be yet wiser; teach a just man, and he will increase in learning."—Proverbs ix.

      Knowledge of Medicine enables the physician to overcome the ravages of disease, and to save suffering patients from sinking prematurely to the grave.

      Knowledge of Anatomy and of Surgery enables the surgeon to bind up dangerous fractures and wounds, and to remove, even from the internal parts of bodies, ulcers and diseased formations that would otherwise be fatal to life.

      Knowledge of Mechanics enables man to increase his power by the construction of machines. The steam-ship crossing the ocean in opposition to wind and tide, the railway locomotive travelling at 60 miles an hour, and the steam-hammer beating blocks of iron into useful shapes, are evidences of the power which man acquires through a knowledge of mechanics.

      Knowledge of Electricity enables man to stand in comparative safety amid the awful war of the elements. Lightning, the offspring of electricity, has a tendency to strike upon lofty objects by which it may be attracted. By its mighty powers churches or houses may be instantly levelled with the dust. But man, knowing that electricity is strongly attracted by particular substances, raises over lofty buildings rods of steel communicating with bars that descend into the ground. The lightning, rushing with indescribable force toward the steeple, is attracted by the bar of steel, and conducted harmlessly to the earth. Man may thus be said to take even lightning by the hand, and to divert its destroying force by the aid of Knowledge. And in countless other instances "Knowledge is Power."

CHAPTER II.

       Table of Contents

      4. Why do we breathe air?

      Because the air contains oxygen, which is necessary to life.

5. Why is oxygen necessary to life?

      Because it combines with the carbon of the blood, and forms carbonic acid gas.

      "Be not as the horse, or as the mule, which have no understanding: whose mouth must be held with the bit and bridle."—Psalm xxxii.

      6. Why is this combination necessary?

      Because we are so created that the substances of our bodies are constantly undergoing change, and this resolving of solid matter into a gaseous form, is the plan appointed by our Creator to remove the matter called carbon from our systems.

7. Why do our bodies feel warm?

      Because, in the union of oxygen and carbon, heat is developed.

      8. What is this union of oxygen and carbon called?

      It is called combustion, which, in chemistry, means the decomposition of substances, and the formation of new combinations, accompanied by heat; and sometimes by light, as well as heat.

9. What