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CHAPTER I. INTRODUCTION. Our distance from the old world, and the favorable circumstances in which we have been placed with respect to the other nations of the new world, have made it so easy for our government to adhere to a pacific policy, that, in the sixty-two years that have elapsed since the acknowledgment of our national independence, we have enjoyed more than fifty-eight of general peace; our ... more...

CHAPTER I. STATESMANSHIP IN ITS RELATION TO WAR. Under this head are included those considerations from which a statesman concludes whether a war is proper, opportune, or indispensable, and determines the various operations necessary to attain the object of the war. A government goes to war,— To reclaim certain rights or to defend them; To protect and maintain the great interests of the state, ... more...

DEFINITIONS DEFIN. I. By the Rays of Light I understand its least Parts, and those as well Successive in the same Lines, as Contemporary in several Lines. For it is manifest that Light consists of Parts, both Successive and Contemporary; because in the same place you may stop that which comes one moment, and let pass that which comes presently after; and in the same time you may stop it in any one place, and ... more...

ANNOUNCER In the year 1661 Connecticut received from the hand of Charles the Second a very liberal charter granting to the people of the colony almost complete self-government and to the colony an enormous stretch of territory extending westward to the Pacific Ocean. For fifteen years the colony prospered under the generous charter. Then in 1676 trouble arose with the Governor of New York, Sir Edmund Andros, ... more...

CHAPTER ONE THE DEVELOPMENT OF ELECTRICITY The phenomenon which Thales had observed and recorded five centuries before the birth of Christ aroused the interest of many scientists through the ages. They made various practical experiments in their efforts to identify the elusive force which Thales had likened to a 'soul' and which we now know to have been static electricity. Of all forms of energy, ... more...

ELECTRICITY AND MATTER My Dear Son: You are interested in radio-telephony and want me to explain it to you. I’ll do so in the shortest and easiest way which I can devise. The explanation will be the simplest which I can give and still make it possible for you to build and operate your own set and to understand the operation of the large commercial sets to which you will listen. I’ll write you a ... more...

CHAPTER I. THE POWER OF THE AIR. "That's it, Jack. Let her out!" "Suffering speed laws of Squantum, but she can travel!" exclaimed Dick Donovan, redheaded and voluble. "I tell you, electricity is the thing. Beats gasoline a million ways," chimed in Tom Jesson. Tom sat beside his cousin, Jack Chadwick, on the driver's seat of a curious-looking automobile which was whizzing down the smooth, broad, ... more...

I COMMUNICATION AMONG THE ANCIENTS     Signaling the Fall of Troy—Marine Signaling among the    Argonauts—Couriers of the Greeks, Romans, and    Aztecs—Sound-signaling—Stentorophonic Tube—The Shouting    Sentinels—The Clepsydra—Signal Columns—Indian Fire and ... more...

Advantages of Common-Battery Operation. The advantages of the common-battery system of operation, alluded to in Chapter XIII, may be briefly summarized here. The main gain in the common-battery system of supply is the simplification of the subscribers' instruments, doing away with the local batteries and the magneto generators, and the concentration of all these many sources of current into one single source ... more...

CHAPTER I ACOUSTICS Telephony is the art of reproducing at a distant point, usually by the agency of electricity, sounds produced at a sending point. In this art the elements of two general divisions of physical science are concerned, sound and electricity. Sound is the effect of vibrations of matter upon the ear. The vibrations may be those of air or other matter. Various forms of matter transmit sound ... more...