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Historic Electric Apparatus

By H. Winfield Secor,





In the present article, describing historic electric apparatus, you will find many facts not generally known. For instance, did you know that the first electric telegraph was actually worked in 1774, by Le Sage, a Frenchman residing in Geneva, Switzerland? Did you know that incandescent electric lamps, employing a carbonized paper filament burning in a vacuum were successfully constructed as far back as 1845? This lamp was invented by a Yankee, Mr. Starr of Cincinnati, Ohio. The first successful arc lamp with automatic carbon feeding mechanism was built about the same time, by an Englishman named Wright. The history of these electric inventions is a real romance.



THE present article is an endeavor to refresh the minds of our electrical students with the antecedents of the wonderful present-day electrical inventions. Like every invention or science, the art of electricity has had its full share of struggling inventors and laugh-producing inventions.

The early inventions in electrical science here discust are not necessarily the very first effort made in each respective line, but are those which are given credit historically, being the fundamental ones from which all later practical applications developed.

One of the first electrical phenomenon experimented with, was that of static electricity. Fig. 1 shows the first static machine as devised by Otto Von Guericke, of Magdeburg, Germany, in the year 1630. The illustration shows Von Guericke and also his machine, which consisted of a globe of sulfur fixt upon a rotatable spindle so that it could be revolved rapidly by means of a crank. Powerful static electric shocks were obtained from this relatively crude device by pressing against the surface of the sulfur ball with the hand, while it was being turned.

The Voltaic pile illustrated in Fig. 2 was invented by Alessandro Volta in 1775. This device was the first to produce what is properly known as voltaic (also called galvanic) electricity. This battery was made by placing a pair of discs of zinc and copper in contact with one another, then laying on the copper disc a piece of flannel or blotting paper, moistened with brine; then another pair of discs of zinc and copper, etc., each pair of discs in the pile being separated by moist conductor. Such a pile, if composed of a number of such pairs of discs will produce electricity enough to give quite a perceptible shock, if the top and bottom disc terminal wires be touched simultaneously with the moist fingers. Volta is given credit for laying the foundation of all present day batteries.

The first electric telegraph of which we have historic record, and also that on which most writers and authorities agree, is that of George Louis Le Sage, a Frenchman residing in Geneva, Switzerland, and who built his first telegraph in 1774. The Le Sage telegraph system employed 24 wires, placed in a trough in the ground, the wires being suitably spaced and insulated by means of glass partitions at frequent intervals. Each wire represented a certain letter of the alphabet. As ft known, gold leaf is extremely sensitive to minute electric impulses, and so we find that Le Sage placed a small piece of gold leaf at the end of each wire. To send a signal over any particular wire corresponding to a certain letter of the alphabet, a small static charge was sent thru the wire by touching it at the transmitting station with a glass rod which had previously been electrically excited by rubbing it with silk. This system was rather limited in its application, as it is very difficult to insulate a static charge for any great distance.

The next serious form of electric telegraph devised was that of Soemmering, bearing the date of 1808, Munich, Germany. This is the machine illustrated in Fie. 3. It operated on a very ingenious principle; viz., that of the electrolysis of water by the passage of an electric current thru it. This inventor used a wire for each letter, the same as Le Sage, and to send a signal over any certain wire, but the wire in this case could be of considerable length. With this system it was but necessary to pass a small battery current thru the proper wire, which caused the water in the indicating device at the opposite end of the line to be decomposed, this indication being evidenced by the production of a large amount of (hydrogen) gas bubbles in the water.

The first electric motor is undoubtedly of interest to every electrician. Early in the 19th century a number of philosophers became much interested in the effect of electric current carrying conductors, especially in their reaction when placed in the field of a magnet. With respect to the first electric motor devised, credit is invariably given to Michael Faraday, who devised the first electro- magnetic rotation apparatus in the year 1822. Barlow in 1823 produced the rotation of a star wheel placed in the field of a strong magnet as shown in Fig. 4. These devices were very crude and simple however, and developed infinitesimal power. Undoubtedly the first electric motor employing electromagnets wound with many turns of wire, and also comprising a motor which utilized both permanent steel magnets and electromagnets, was that perfected by Prof. Joseph Henry, of Princeton University, in the year 1831. Henry produced reciprocating motion as well as the rotary motion by electro-magnetic means. Henry's motor of the vintage of 1831 is also shown in Fig. 4. This was the forerunner of the present day electric motor of which there are many hundred thousands in use in all parts of the world. Henry's device interrupted the battery current by its oscillating or rotary motion in an intermittent manner in either case. It is interesting to note that Henry called his motor a "philosophical toy." In studying the history of electric motors and dynamos it is well to keep in mind this first electro-magnetic motor of Professor Henry's, which fact will be further touched upon in the present article, as it had a very important bearing on certain other inventions.

The dynamo, which produces electricity by rotating an inductor or series of inductors in the field of a powerful magnet, was first studied on the basis of a peculiar phenomenon. The first experiment in this field reverts back to what is known as Arago's disc. This consisted of a brass or copper disc which, when rotated at considerable speed and placed below a magnetized compass needle, caused that needle to be dragged around. These "Arago's rotations," as they were called, were supposed to be some kind of mysterious magnetic rotation, until Faraday proved them to be due to induction and simply obeying a basic law of electro-magnetism. The next definite step in the development of the dynamo as a producer of electricity by electro-magnetic means was in 1831, when Faraday made his first experiments with a revolving copper disc placed between the poles of a very powerful magnet. In some of these experiments, a copper disc was allowed to dip in a trough containing mercury; the electric current being taken from the axle support ing the disc, and from the mercury trough in which the disc dipt as it was rotated by means of a crank handle.

About a year later Pixii devised an electro-magnetic dynamo as shown also in Fig. 5, which involved the use of a revolving permanent steel-magnet placed below two iron cores containing coils of wire. By means of driving gears and a handle as shown in the illustration, Pixii was able to produce quite strong alternating currents with his dynamo as the permanent magnet spun around below the magnet coils at high speed.

The trolley car, with which we are all familiar today, and which moreover seems so simple that it would almost appear to have always been with us, instead of passing thru many stages of evolution, was distinctly an American invention. Going back to the work of Prof. Joseph Henry and the electric motor, it is recorded that Thomas Davenport, a New England philosopher who was residing in Vermont, went to see one of Prof. Henry's powerful electro-magnets in operation at a manufacturing plain where the magnet was in use for the pin pose of removing iron from clay and other materials. This was about the year 1833. and Davenport was much imprest by tin great power of the then new electro-magnets, one of which he saw demonstrated by lifting a heavy steel anvil when excited by three battery cells.

Davenport did much thinking on this subject and at once started building models of electric motors, and he is given credit for producing the first electric railway in 1835 History records that Davenport actually made over one hundred models of electric motors in the period from 1835 to 1840. These included motors of every conceivable type and variety, both with electro-magnets and permanent magnets. He exhibited an excellent model of his proposed electric railway in Boston in 1840. Davenport, so we learn, was not an educated technician or true philosopher of the college-bred type, but was a natural born genius, and it is said of him that he surely realized the wonderful basic principle which underlies even electric motor and dynamo today; i.e., that to obtain the maximum and most satisfactory results, there shall be two distinct magnetic fields employed, one of which shall be of permanent polarity, and the other of which shall be of constantly changing polarity.

The first incandescent electric lamp has been a bone of contention for a great man; years, and much mystery surrounds the early days of the incandescent lamp. Most historical electrical treatises give credit for the first incandescent lamp to Sir Humphrey Davy, who exhibited this type of illuminant (first demonstration in 1802) in the year 1810. He did not enclose his incandescent lamp in a vacuum or in a tube however, but contented himself with bringing a strip of platinum 1/30 of an inch thick by 18 inches in length to a high state of brilliance by connecting it to a large number of batteries. Little was done in succeeding years to evolve any form of incandescent electric lamp, and the next we hear of this now universal illuminant is in 1841, when we find the work of de Moleyns.

His incandescent lamp utilized a fine platinum wire. About the first incandescent lamp of the exhausted bulb type that we find a record of, is that due to Starr, a Yankee inventor of Cincinnati, Ohio. His first product bears the date of 1845, when he took out a patent for a carbon filament lamp with an exhausted bulb. He took out many patents, and evolved a diversified number of incandescent lamps and filaments, but owing to the lack of commercial dynamos, success in those days was of short duration.

Another earnest worker in this field was Henrich Gobel, of New York City, who produced a very promising carbon filament lamp in 18S4. Gobel first used wood charcoal for the filament, and later tried carbonized bamboo.

The Edison incandescent lamp upon which large sums of money were spent in development for several years, finally emerged from the laboratory in 1879, and from that date progress was real and assured in the development of electric lighting. The illustration in Fig. 7 shows the earliest form of incandescent lamp, and also the Edison lamp as first manufactured. The Edison lamp had an exhausted bulb, and a carbon filament was used composed of carbonized brown paper at first, but shortly afterward this was made of carbonized bamboo. Thousands of different kinds of filament and materials for them were exhaustively tested out in Edison's laboratory, and it is surprising to learn that even in those days there were a number of inventors who proposed metallic filament lamps, and actually tried out incandescent lamps, having filaments coated with metallic oxids, etc.

The arc lamp, which is very common now-a-days, was invented by Sir Humphrey Davy, who discovered in 1801, that by connecting up a large number of battery cells to a pair of pointed carbon rods, that when these rods were placed in contact and then separated, an electric arc of great brilliance tended to form between the carbons.

In 1809, Davy exhibited publicly the first electric arc light, which was excited by two thousand primary battery cells. Arc lights languished for a good many years until an Englishman by the name of Wright, in 1844, devised the first successful automatic self-feeding arc lamp. Wright's ingenious automatic arc lamp is shown in Fig. 8, as also Davy's first arc lamp of the hand-feed type.

Wright's arc lamp comprised a series of carbon discs with bevelled edges, arranged in the manner illustrated. Two of these discs were movable; thus making it possible to compensate for the change in the length of the arc as the discs were burnt away, and all of the carbon discs were rotated while the lamp was in operation by means of clock-work mechanism.

The telephone, now in use in practically every city and community all over the civilized world, first saw the light of day in Germany (1861) in the apparatus invented by Philip Reis, instructor in natural sciences at Professor Garnier's Institute, a select school for boys at Friedrichsdorf, near Homburg. As Professor Sylvanus P. Thompson has declared - "the apparatus devised by Reis was the employment of a loose or imperfect contact between two parts of a conducting circuit so that the pressure and electrical resistance might be varied by differing stress." By this system (see Fig. 9) Reis was able to transmit musical sounds, especially whistling and other shrill tones, with all variations of pitch and loudness, altho without timbre, probably resembling somewhat the sound of a xylophone (wooden piano) - and less perfectly, also, the sounds of the human voice; the consonants being readily represented, but the vowels less distinctly, if at all.

Referring to this early forerunner of the wonderful telephone which Professor Bell (1876) later perfected so as to be able to transmit articulate speech over any distance by electrical means, we find that Reis used as a transmitter, a small box having two openings, one at the side for the mouthpiece, and the other at the top, closed by a diafram, made from the smaller intestine of a pig. At the center of this membrane was cemented a strip of platinum in loose contact with the point of a platinum wire held in position above it by a light leaf spring. The receiver of the Reis system comprised a steel wire, wrapt around with a coil of insulated wire, thus forming an electro-magnet. This was mounted on a small resonant wooden box resembling a violin, and which served as a sounding board. To this was later added a cover of thin wood, against which the ear could be prest to receive the sounds transferred along the wire electrically from the transmitter.

Wireless telegraphy for practical purposes really dates back to the brilliant scientific researches of Henrich Hertz. Many electrical writers date wireless telegraphy back to the first wireless transmission of messages to 1838 when Professor Joseph Henry, of Princeton University, succeeded in setting up induced currents in the cellar of a building, when a Leyden jar was charged and discharged by means of a static electrical machine placed in the top room of his residence. Next in line to be credited by many writers is Professor S. F. B. Morse, who is stated by one authority ("Wireless Telegraphy," by Sewall, 1904) to have actually sent the first signal without wires on December 16th, 1842, when he succeeded in sending a wireless telegram across a canal 80 feet in width, and in November, 1844, Mr. A. D. Gale, under the instruction of Professor Morse, transmitted wireless signals across the Susquehanna River at Havre de Grace, a distance of nearly one mile.

This wireless scheme, however, was based on the principle of conduction, and thus was limited in its application and in the range that could be covered. Considerable experiment was done with inductive systems of wireless telegraphy and telephony, in America, from 1882 to 188S by Professor Dolbear and Thomas A. Edison, the latter investigator having successfully signaled thru space to a moving train from a wire installed on poles beside the railway, in 1885.

The crowning achievement in the realm of radio-telegraphy by etheric wave transmission was that of Hertz, in 1886. Across a small spark gap in a ring of wire suspended in a room (there having been no electrical contact with the charging apparatus), Hertz caused tiny sparks to appear as the result of the passage across another and longer spark gap of the oscillatory discharge from a Leyden jar. Finally we come to the work of Guglielmo Marconi, whose successful publisht experiments date from 1896, when he succeeded in transmitting wireless signals by means of Hertzian waves in the ether across a space of 100 yards at the British Postoffice in London. Soon afterwords he made a successful trial of sending and receiving wireless signals over a distance of two miles on Salisbury Plain, and from then on, the art of radio signaling advanced by leaps and bounds, and it was but a few years, or to be exact on Thursday, Dec. 12, 1901, at 12:30 P. M., when Marconi received the first wireless signal across the Atlantic Ocean (over 2,000 miles) between Poldhu, England, and Cape Cod, Mass., this immortal radio signal having been the letter "S" as represented telegraphically by three dots.



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