Alfred Powell Morgan

“ All bodies which produce sounds are in a state of vibration, and they communicate their vibrations to the surrounding air and thus set it into waves, just as a stick waved back and forth in a pool of water creates ripples. ”

“ The nerves of every war vessel and fort are the wires of the telephones, telegraphs, telautographs, dynamos, storage batteries etc., that transmit orders by speech or in writing, find the range, fire the guns, explode the mines and seek out the enemy with a powerful searchlight.
Every battle-ship, cruiser, etc., of the United States Navy is now equipped and with the completion of the new ultrapowerful station at Washington the War Department will be enabled to issue instructions to a ship no matter where it may be on the ocean or in what harbor it may lie. ”

“ This seething mass of flame and heat furnishes us more than mere winter and summer and night and day, for we on this earth are not living on our own resources, and the real work of the world so necessary for even bare existence is accomplished by the energy of the sun stored up in coal, in plants and trees and mountain torrents. ”

“ A decade later and aeroplanes have become a living reality. A man and a little frame of sticks and canvas can throw off the fetters of gravity and go soaring dizzily two miles up into the blue sky, and daring more, come skimming and diving back to earth with motor dead. Such wonders only came to pass, however, when numbers of men accepted the problem as one to be solved by trying, and bent their energies toward its solution. Science has not reached the limits of its resources. It never will. The art of wireless may always be embarrassed by novelty in many directions.
FIG. 154. ”

“ There are many places in the world where water power is available capable of generating almost unlimited electrical energy. The present difficulty lying in the way of its utilization is the limitation of electrical transmission by wire, for not only is the cost of long lines of copper tremendous, but power can only be carried in this manner for limited distances. Central distributing wireless power stations could send the power of Niagara, which alone might be made to supply a fifth of all the power in the United States, and the energy of Victoria to the ends of the earth with little loss. ”

“ The wonderful mysteries of oscillatory currents, whose natural medium is the ether, currents which object to being confined to wires and cables, and defy all ordinary laws; currents that will melt masses of metal with the violence of an explosion, but yet pass through the human body without producing any sensation; currents that will instantly manifest themselves 2,000 miles away from their source, with no visible means of propagation, are the open sesame to the treasures of a wonderful future. ”

“ The best known expert in all branches of engineering have contributed to these volumes. The Cyclopedia is admirably well adapted to the needs of the beginner and the self-taught practical man, as well as the mechanical engineer, designer, draftsman, shop superintendent, foreman, and machinist. The work will be found a means of advancement to any progressive man. It is encyclopedic in scope, thorough and practical in its treatment of technical subjects, simple and clear in its descriptive matter, and without unnecessary technicalities or formulae. ”

“ The need for such a work has been felt by most engineers engaged in the construction and working of Marine Engines, not only by the younger men, but also by those of greater experience. The fact that the original German work was written by the chief engineer of the famous Vulcan Works, Stettin, is in itself a guarantee that this book is in all respects thoroughly up-to-date, and that it embodies all the information which is necessary for the design and construction of the highest types of marine engines and boilers. ”

“ Wireless telegraph instruments are simply a means for creating and detecting waves in a great pool of ether.
Scientists suppose that all space and matter is pervaded with a hypothetical medium of extreme tenuity and elasticity, called luminiferous ether, or simply ether.
Although ether is invisible, odorless, and practically weightless, it is not merely the fantastic creation of speculative philosophers, but is as essential to our existence as the air we breathe and the food we eat. By imagining and accepting its reality, it is possible to explain and understand many scientific puzzles. ”

“ What really passes out from the source is merely a rhythmical motion of the air particles, manifesting themselves as changes in pressure, spreading out in ever-widening spheres through the atmosphere. The order of these compressions is different for every sound. The musical sounds of an orchestra embody a different set of vibrations for each note of each particular instrument. If the fluctuations in pressure of a sound wave are irregular and non-periodic, the sound is called a noise; if they are cyclic, and follow a regular and sufficiently rapid periodic lag, the sound is musical. ”

“ The greatest obstacle to all efforts in radically new directions is the resistance of the human race. The antagonism of prejudice and skepticism can only disappear when the world as a whole grasps a new proof and learns to appreciate it. ”

“ A general diffusion of waves is often very undesirable for the reasons that the message may be received by an unfriendly neighbor or enemy and also because it is wasteful of energy. By so directing the waves that they may be sent over the earth to any desired point of the compass and only in that direction, it is possible to communicate without disturbing another station and also for a vessel at sea to secure its bearings and position by tuning its apparatus to respond to electric waves from two different known stations. ”

“ The cause of lightning is the accumulation of electric charges in the clouds. The electricity resides on the surface of the particles of water in the cloud. These charges grow stronger as the particles of water coalesce to form larger drops, because, as they unite, the surface increases proportionally less than the volume and, being forced to lodge on a smaller space, the electricity becomes more "concentrated," so to speak. For this reason the combined charge on the surface of the larger drop is more intense than were the charges on the separate particles, and the "potential" is increased. ”

“ MODERN AMERICAN LATHE PRACTICE. By OSCAR E. PERRIGO. This is a new book from cover to cover, and the only complete American work on the subject written by a man who knows not only how work ought to be done, but who also knows how to do it, and how to convey this knowledge to others. It is strictly up-to-date in its descriptions and illustrations, which represent the very latest practice in lathe and boring mill operations as well as the construction of and latest developments in the manufacture of these important classes of machine tools. ”

“ In breathing, the air to and from the lungs passes freely between the chords. When the controlling muscles are tightened, so as to stretch the chords, the edges are also brought parallel and quite close to each other. If the breath from the lungs is then forced through the narrow slit between them, they vibrate like the reed of a musical instrument, and produce the sounds of the voice. ”

“ Suppose that an induction coil, having a high-speed interruptor, and therefore able to produce a very rapid stream of sparks at the gap, is connected to the aerial and ground in the usual manner and a telephone transmitter placed in series with the ground wire. When the coil is set in operation the sparks jump across the gap, each spark setting up a train of oscillations. If speech is conveyed into the transmitter, the resistance in the path of the oscillations will be varied and correspondingly also the strength of the waves emitted. ”

“ Any one whose imagination is vivid enough can make a prediction, but when the great truth is accidentally revealed, or experimentally confirmed, as the case may be, and rendered absolutely sure of accomplishment, will its incalculable consequences continue to baffle the imagination and carry us further into the land of wonderment? ”

“ One of the greatest disadvantages of most systems of wireless telegraphy lies in the fact that no arrangement is provided for simultaneously transmitting and receiving wireless signals. It is usually necessary for one operator listening to another to have to wait until the finish signal is given before he can reply or interrupt in case he cannot understand part of the message, because the receiving apparatus of the transmitting station is necessarily disconnected from the aerial and the ground during the period a message is being sent. ”

“ No shop can afford to be without it. It bristles with valuable wrinkles and helpful suggestions, It will benefit all, from apprentice to proprietor. Every machinist, at any age, should study its pages. ”

“ The studies to be followed, methods of work, field of operation and the requirements of the successful electrician are pointed out and fully explained. Every young engineer will find this an excellent stepping-stone to more advanced works on electricity which he must master before success can be attained. Many young men become discouraged at the very out-start by attempting to read and study books that are far beyond their comprehension. ”

“ Wireless telegraphy is part of the established order of things. The wireless telephone is practical for limited distance, but is not a commercial rival of the telegraph. Great distances are claimed, but they are matters for proof and speculation.
There is no immediate possibility that wireless telephony will take the place of local exchanges. If the time ever does come that it in any way tends to supplant the line telephone for some uses, it is more than probable that each subscriber must have his own generating station and call up direct. ”

“ Only a few years ago Langley launched his famous aerodrome over the waters of the Potomac, while the world stood by and sneered, ridiculed a man whose work is now one of the classics of aeronautical literature, and scoffed at a machine whose principles embodied the conclusions of years of careful thought and scientific effort. ”

“ The transmission of the vibrations depends upon well known principles of electricity, and consists, not of an actual transmission of the sounds, but the passage of electric waves, or impulses, which keep perfect accord and agree in phase and period with the atmospheric waves produced by the voice. These in turn, through the medium of an electromagnet, cause vibrations of a plate or membrane, which agitates the air in a manner similar to the original disturbance, and thus emits sounds. ”

“ The purpose of the iron core is to concentrate the magnetic field and make the coil more efficient. Since currents are only induced in the secondary when the magnetic field is changing, an automatic device called an interrupter or sometimes a vibrator, is employed to rapidly turn the current flowing through the primary on and off. The interrupter consists of a spring carrying a platinum point against which presses a second piece of platinum on the end of an adjustable thumbscrew. Platinum is necessary because the current of electricity would quickly oxidize and burn up any other material. ”

“ Both the induction coil and transformer depend for their operation upon the principles of magnetic induction. In 1831, Michael Faraday, a famous English chemist and physicist, discovered that if a magnet be suddenly plunged into a hollow coil of wire, that a momentary current of electricity is generated in the coil. As long as the magnet remains motionless, it induces no current in the coil, but when it is moved back and forth, it sets up the currents. The source of electrical energy is the mechanical work done in moving the magnet. ”

“ When a battery is used in connection with a detector a condenser is also necessary to oppose the direct current of the battery and prevent it from flowing around through the tuning coil instead of through the detector. The capacity of the condenser may be smaller if the resistance of the telephone receiver is very great for the reason that as the wire grows smaller it offers greater impedance to the current. ”

“ Indicating as it does, in every line, the familiarity of the author with every detail of daily experience in the shop, it cannot fail to be of service to any man practically connected with the shaping or finishing of metals. There is nothing experimental or visionary about the book, all devices being in actual use and giving good results. It might be called a compendium of shop methods, showing a variety of special tools and appliances which will give new ideas to many mechanics, from the superintendent down to the man at the bench. ”

“ In summer the trees are full of sap and, being much better conductors of electricity when in this condition, act in the capacity of innumerable aerials rising in the air, and able to absorb appreciable amounts of energy. During these same months the air becomes highly ionized, in which state the air molecules carry an electric charge, and are particularly opaque to the waves. This condition also usually exists in the presence of sunlight, the result being that the most favorable time for the wireless transmission of messages are the hours around midnight. ”

“ Let us consider briefly how the waves are created in a wireless telegraph station. Almost every one has seen and heard the brilliant snapping spark produced by the discharge of a Leyden jar. A Leyden jar in its common form is a glass jar lined inside and out with tinfoil for about two thirds of its height. A brass rod, terminating in a knob, connects below with the inner coating, usually by means of a loose chain. It may be described as a device which is capable of storing electricity in the form of energy and discharging this energy again in actual electricity. ”