Technology & Engineering Books

Induction of Electric Currents. 6. About twenty-six feet of copper wire one twentieth of an inch in diameter were wound round a cylinder of wood as a helix, the different spires of which were prevented from touching by a thin interposed twine. This helix was covered with calico, and then a second wire applied in the same manner. In this way twelve helices were superposed, each containing an average... more...

FACTS AND OBSERVATIONS ON THE SALMON. In the following observations I intend to offer some remarks on the various migratory fish of the genus Salmo; and then some facts and opinions which tend to show the importance of some change in the laws which are now in force regarding them. We have first the Salmon; which, in the Ribble, varies in weight from five to thirty pounds. We never see the fish here... more...

CHAPTER I Our object in reading and studying this book is to find out some facts that will help those of us who are thinking of going into farming and gardening as a business or recreation to start right, and will also help those of us that are already in the business to make our farms and gardens more productive. In order to make the book of greatest value to you, I would urge you not only to read and... more...

MY EXCUSE My sixtieth birthday is a thing of yesterday, and I have, therefore, more than half descended the western slope. I have no quarrel with life or with time, for both have been polite to me; and I wish to give an account of the past seven years to prove the politeness of life, and to show how time has made amends to me for the forced resignation of my professional ambitions. For twenty-five... more...

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 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... 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... more...

CHAPTER I. "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,... 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, as... more...