 Appendix 18 of Edison, His Life and Inventions. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Recording by Jerome Lawson, January 2008. Edison, His Life and Inventions by Frank Louis Dyer and Thomas Cumberford Martin. Appendix 18, Edison's new storage battery. Generically considered, a battery is a device which generates electric current. There are two distinct species of battery, one being known as primary and the other as storage. Although the latter is sometimes referred to as a secondary battery or accumulator, every type of each of these two species is essentially alike in its general makeup. That is to say, every cell or battery of any kind contains at least two elements of different nature, immersed in a more or less liquid electrolyte of chemical character. On closing the circuit of a primary battery, an electric current is generated by reason of the chemical action which is set up between the electrolyte and the elements. This involves a gradual consumption of one of the elements and a corresponding exhaustion of the active properties of the electrolyte. By reason of this, both the element and the electrolyte that have been used up must be renewed from time to time in order to obtain a continued supply of electric current. The storage battery also generates electrical current through chemical action, but without involving the constant repriming with active materials to replace those consumed and exhausted as above mentioned. The term storage as applied to this species of battery is however a misnomer and has been the cause of much misunderstanding to non-technical persons. To the lay mind, a storage battery presents itself in the aspect of a device in which electric energy is stored just as compressed air is stored or accumulated in a tank. This view however is not in accordance with facts. It is exactly like the primary battery in the fundamental circumstance that its ability for generating electric current depends upon chemical action. In strict terminology, it is a reversible battery, as will be quite obvious if we glance briefly at its philosophy. When a storage battery is charged by having an electric current pass through it, the electric energy provides a chemical effect, adding oxygen to the positive plate and taking oxygen away from the negative plate. Thus the positive plate becomes oxidized and the negative plate reduced. After the charging operation is concluded, the battery is ready for use and upon its circuit being closed through a translating device, such as a lamp or motor, a reversion discharge takes place. The positive plate giving up its oxygen and the negative plate being oxidized. These chemical reactions result in the generation of an electric current as in a primary battery. As a matter of fact, the chemical actions and reactions in a storage battery are much more complex, but the above will serve to afford the lay reader a rather simple idea of the general result arrived at through the chemical activity referred to. The storage battery, as a commercial article, was introduced into the market in the year 1881. At that time, and all through the succeeding years, until about 1905, there was only one type that was recognized as commercially practicable, namely that known as the lead-sulfuric acid cell, consisting of lead plates immersed in an electrolyte of dilute-sulfuric acid. In the year last named, Edison first brought out his new form of nickel-iron cell with alkaline electrolyte as we have related in the preceding narrative. Early in the 80s, at Menlo Park, he had given much thought to the lead type of storage battery and during the course of three years had made a prodigious number of experiments in the direction of improving it, probably performing more experiments in that time than the aggregate of those of all other investigators. Even in those early days, he arrived at the conclusion that the lead-sulfuric acid combination was intrinsically wrong and did not embrace the elements of a permanent commercial device. He did not at that time, however, engage in a serious search for another form of storage battery, being tremendously occupied with his lighting system and other matters. It may here be noted, for the information of the lay reader, that the lead-acid type of storage battery consists of two or more lead plates immersed in dilute-sulfuric acid and contained in a receptacle of glass, hard rubber, or other special material non-acted upon by acid. The plates are prepared and formed in various ways and the chemical actions are similar to those above stated. The positive plate being oxidized and the negative reduced during charge and reversed during discharge. This type of cell, however, has many serious disadvantages inherent to its very nature. We will name a few of them briefly. Constant dropping of fine particles of active material often causes short circuiting of the plates and always necessitates occasional washing out of cells. Deterioration through sulfation, if discharges continue too far or if recharging is not commenced quickly enough. Destruction of adjacent metalwork by the corrosive fumes given out during charge and discharge. The tendency of lead plates to buckle under certain conditions. The limitation to the use of glass, hard rubber, or similar containers on account of the action of the acid, and the immense weight for electrical capacity. The tremendously complex nature of the chemical reactions which take place in the lead acid storage battery also renders it an easy prey to many troublesome diseases. In the year 1900, when Edison undertook to invent a storage battery he declared it should be a new type into which neither sulfuric nor any other acid should enter. He said that the intimate and continued companionship of an acid and a metal was unnatural and incompatible with the idea of durability and simplicity. He furthermore stated that lead was an unmechanical metal for a battery being heavy and lacking stability and elasticity and that as most metals were unaffected by alkaline solutions he was going to experiment in that direction. The soundness of his reasoning is amply justified by the perfection of results obtained in the new type of storage battery bearing his name and now to be described. The essential technical details of this battery are fully described in an article written by one of Edison's laboratory staff, Walter E. Holland who for many years has been closely identified with the inventor's work on this cell. The article was published in the Electrical World, New York, April 28, 1910 and the following extracts therefrom will afford an intelligent comprehension of this invention. The A-type Edison cell is the outcome of nine years of costly experimentation and persistent toil on the part of its inventor and his associates. The Edison invention involves the use of an entirely new voltaic combination in an alkaline electrolyte in place of the lead, lead peroxide combination and acid electrolyte characteristic of all other commercial storage batteries. Experience has proven that this not only secures durability and greater output per unit weight of battery but in addition there is eliminated a long list of troubles and diseases inherent in the lead-acid combination. The principle on which the action of this new battery is based is the oxidation and reduction of metals in an electrolyte which it does not combine with and will not dissolve either the metals or their oxides and an electrolyte furthermore which although decomposed by the action of the battery is immediately reformed in equal quantity and therefore in effect is a constant element not changing in density or in conductivity. A battery embodying this basic principle will have features of great value where lightness and durability are desired. For instance, the electrolyte being a constant factor as explained is not required in any fixed and large amount as is the case with sulfuric acid in the lead battery. Thus the cell may be designed with minimum distancing of plates and with the greatest economy of space that is consistent with safe insulation and good mechanical design. Again, the active materials of the electrodes being insoluble in and absolutely unaffected by the electrolyte are not liable to any sort of chemical deterioration by action of the electrolyte no matter how long continued. The electrolyte of the Edison battery is a 21% solution of potassium hydrate having in addition a small amount of lithium hydrate. The active metals of the electrodes which will oxidize and reduce in this electrolyte without dissolution or chemical deterioration are nickel and iron. These active elements are not put in plates as metals but one nickel in the form of a hydrate and the other iron as an oxide. The containing cases of both kinds of active material figure one and their supporting grids figure two as well as the bolts, washers and nuts used in assembling. Figure three and even the retaining can in its cover figure four are all made of nickel plated steel a material in which lightness, durability and mechanical strength are most happily combined and a material beyond suspicion as to corrosion in an alkaline electrolyte. An essential part of Edison's discovery of active materials for an alkaline storage battery was the preparation of these materials. Metallic powder of iron and nickel or even oxides of these metals prepared in the ordinary way are not chemically active in a sufficient degree to work in a battery. It is only when specially prepared iron oxide of exceeding fineness and nickel hydrate conforming to certain physical as well as chemical standards can be made that the alkaline battery is practicable. Needless to say, the working out of the conditions and processes of manufacture of the materials involved great ingenuity and endless experiments. The article then treats of Edison's investigations in demeans for supporting and making electrical connection with the active materials, showing some of the difficulties encountered and the various discoveries made in developing the perfected cell after which the writer continues his description of the A type cell as follows. It will be seen at once that the construction of the two kinds of plate is radically different. The positive or iron plate, figure five, has the familiar flat pocket construction. Each negative contains 24 pockets, a pocket being one half inch wide by three inches long and having a maximum thickness of a little more than one eighth inch. The positive or nickel plate, figure six, is seen to consist of two rows of round rods or pencils, 30 in number, held in a vertical position by a steel support frame. The cells have flat flanges at the ends, formed by closing the metal case, by which they are supported and electrical connection is made. The frame is slit at the inner horizontal edges and then folded in such a way as to make individual clamping jaws for each end flange. The clamping in is done at great pressure and the resultant plate has great rigidity and strength. The perforated tubes into which the nickel active material is loaded are made of nickel plated steel of high quality. They are put together with a double-lap spiral seam to give expansion-resistant qualities and as an additional precaution, small metal rings are slipped on the outside. Each tube is one quarter inch in diameter by four and one eighth inches long and has eight of the reinforcing rings. It will be seen that the A positive plate has been given the theoretically best design to prevent expansion and overcome trouble from that cause. Actual tests, long continued under very severe conditions, have shown that the construction is right and fulfills the most sanguine expectations. Mr. Holland in his article then goes on to describe the development of the nickel flakes as the conducting factor in the positive element. But as this has already been described in Chapter 22, we shall pass on to a later point where he says, an idea of the conditions inside a loaded tube can best be had by microscopic examination. Figure 7 shows a magnified section of a regularly loaded tube which has been sawed lengthwise. The vertical bounding walls are edges of the perforated metal containing tube. The dark horizontal lines are layers of nickel flake while the light colored thicker layers represent the nickel hydrate. It should be noted that the layers of flake nickel extend practically unbroken across the tube and make contact with the metal wall at both sides. These metal layers conduct current to or from the active nickel hydrate in all parts of the tube very efficiently. There are about 350 layers of each kind of material in a 4 1⁄8 inch tube. Each layer of nickel hydrate being about 0.01 inch thick. So it will be seen that the current does not have to penetrate very far into the nickel hydrate. One half a layer's thickness being the maximum distance. The perforations of the containing tube through which the electrolyte reaches the active material are also shown in Figure 7. In conclusion, the article enumerates the chief characteristics of the Edison storage battery which fit it preeminently for transportation service as follows. One, no loss of active material hence no sediment short circuits. Two, no jar breakage. Three, possibility of quick disconnection or replacement of any cell without employment of skilled labor. Four, impossibility of buckling and harmlessness of a dead short circuit. Five, simplicity of care required. Six, durability of materials and construction. Seven, impossibility of sulfation. Eight, entire absence of corrosive fumes. Nine, commercial advantages of light weight. Ten, duration on account of its dependability. And eleven, its high practical efficiency. End of Appendix 18. Recording by Jerome Lawson. January 2008. Appendix 19. Of Edison, his life and inventions. This is the LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Edison, his life and inventions. By Frank Lewis Dyer. And Thomas Comerford Martin. Appendix 19. Edison's poured cement house. The inventions that have been thus far described fall into two classes. First, those that were fundamental in the great arts and industries which have been founded and established upon them. And second, those that have entered into and enlarged other arts that were previously in existence. On coming to consider the subject now under discussion, however, we find ourselves at this writing on the threshold of an entirely new and undeveloped art of such boundless possibilities that its ultimate extent can only be a matter of conjecture. Edison's concrete house, however, involves two main considerations. First of which was the conception or creation of the idea, vast and comprehensive, of providing imperishable and sanitary homes for the wage earner by molding an entire house in one piece in a single operation, so to speak, and so simply that extensive groups of such dwellings could be constructed rapidly and at a very reasonable cost. With this idea suggested one might suppose that it would be a simple matter to make molds and pour in a concrete mixture. Not so, however, and here the second consideration presents itself. An ordinary cement mixture is composed of crushed stone, sand, cement, and water. If such a mixture be poured into deep molds the heavy stone and sand settle to the bottom. Should the mixture be poured into a horizontal mold like the floor of a house the stone and sand settle forming an un-uniform mass. It was at this point that invention commenced in order to produce a concrete mixture which would overcome this crucial difficulty. Edison, with characteristic thoroughness, took up a line of investigation and after a prolonged series of experiments he succeeded in inventing a mixture that upon hardening remained uniform throughout its mass. In the beginning of his experimentation he had made the conditions of test very severe by the construction of forms similar to that shown in the sketch below. This consisted of a hollow wooden form of the dimensions indicated. The mixture was to be poured into the hopper until the entire form was filled. Such mixture flowing down and along the horizontal legs and up the vertical members. It was to be left until the mixture was hard and the requirement of the test was that there should be absolute uniformity of mixture and mass throughout. This was finally accomplished and further invention then proceeded along engineering lines looking towards the devising of a system of molds with which practicable dwellings might be cast. Edison's boldness and breadth of conception are well illustrated in his idea of a poured house in which he displays his accustomed tendency to reverse accepted methods. In fact it is this very reversal of usual procedures that renders it difficult for the average mind to instantly grasp the full significance of the principles involved and the results attained. Up to this time and accustomed to see the erection of a house begun at the foundation and built up slowly piece by piece of solid materials. First the outer frame then the floors and inner walls followed by the stairways and so on up to the putting on of the roof. Hence it requires a complete rearrangement of mental conceptions to appreciate Edison's proposal to build a house from the top downward in a few hours with a freely flowing material poured into molds and in a few days to take away the molds and find a complete, indestructible sanitary house including foundation, frame floors, walls, stairways, chimneys sanitary arrangements and roof with artistic ornamentation inside and out all in one solid piece as if it were graven or bored out of a rock. To bring about the accomplishment of a project so extraordinarily broad involves engineering and mechanical conceptions of a high order and as we have seen these have been brought to bear on the subject by Edison together with an intimate knowledge of compounded materials. The main features of this invention are easily comprehensible with the aid of the following diagrammatic sectional sketch. It should first be understood that the above sketch is in broad outline without elaboration merely to illustrate the working principle and while the upright structure on the right is intended to represent a set of molds in position to form a three-story house with a cellar no regular details of such a building such as window-stores, stairways, etc. are here shown as they would only tend to complicate an explanation. It will be noted that there are really two sets of molds an inside and an outside set leaving a space between them throughout. Although not shown in the sketch there is in practice a number of bolts passing through these two sets of molds at various places to hold them together in their relative positions. In the open space between the molds there are placed steel rods for the purpose of reinforcement while all through the entire structure provision is made for water and steam pipes, gas pipes and electric light wires being placed in appropriate positions as the molds are assembled. At the center of the roof there will be noted a funnel-shaped opening. Into this there is delivered by the endless chain of buckets shown on the left a continuous stream of special free-flowing concrete mixture. This mixture descends by gravity and gradually fills the entire space between the two sets of molds. The delivery of the material or pouring as it is called is continued until every part of the space is filled and the mixture is even with the tip of the roof thus completing the pouring or casting of the house. In a few days afterward the concrete will have hardened sufficiently to allow the molds to be taken away leaving an entire house from cellar to floor to the peak of the roof complete in all its parts moving to the mantels and picture molding and requiring only windows and doors, plumbing, heat and lighting fixtures to make it ready for habitation. In the above sketch the concrete mixers A and B are driven by the electric motor C as the material is mixed it descends into the tank D and flows through a trough into a lower tank E in which it is constantly stirred and from which it is taken a chain of buckets and dumped into the funnel shaped opening at the top of the molds as above described. The molds are made of cast iron in sections of such size and weight as will be most convenient for handling mostly in pieces not exceeding two by four feet in rectangular dimensions. This sub-joint sketch shows an exterior view of several of these molds as they appear when bolted together. The molds represent central portions representing ribs which are included as part of the casting for the purposes of strength and rigidity. The molds represented above are those for straight work such as walls and floors those intended for stairways eaves, cornices, windows doorways, etc. are much more complicated in design although the same general principles are employed in their construction while the philosophy of pouring or casting a complete house in its entirety is apparently quite simple. The development of the engineering and mechanical questions involves the solution of a vast number of most intricate and complicated problems covering not only the building as a whole but its numerous parts down to the minutest detail. Safety, convenience duration and the practical impossibility of altering a one-piece solid dwelling are questions that must be met before its construction and therefore Edison has proceeded calmly on his way toward the goal he has ever had clearly in his mind. With utter indifference to the criticism and jeers of those who, as experts have professed positive knowledge of the impossibility of his carrying out this daring scheme. End of Appendix 19 Arranged according to dates of execution of applications for such patents this list shows the inventions as Mr. Edison has worked upon them from year to year. October 25th, 1870 numbered 4166 and August 5th, 1873 numbered 5519 January 25th, 1869 Number 96567 Apparatus for printing telegraph Reissued February 1st, 1870 numbered 3820 August 17th, 1869 Number 96681 Electrical switch for telegraph apparatus August 27th, 1869 Number 102320 Printing telegraph Pope and Edison Reissued April 17th, 1877 numbered 7621 and December 9th, 1884 numbered 10542 September 16th, 1869 Number 103924 Printing telegraphs Pope and Edison Reissued August 5th, 1873 1870 Number 103035 Electromotor Escapement February 5th, 1870 Number 128608 Printing telegraph instruments May 4th, 1870 Number 114656 Telegraph transmitting instruments June 22nd, 1870 Number 114658 Electromagnets for telegraph instruments June 22nd, 1870 Number 114657 Relay magnets for telegraph instruments September 6th, 1870 Number 11112 Electric motor governors June 29th, 1870 Number 113033 Printing telegraph apparatus November 17th, 1870 1871 Number 113034 Printing telegraph apparatus January 10th, 1871 Number 123005 Telegraph apparatus July 26th, 1871 Number 123006 Printing telegraph July 26th, 1871 Number 123984 Telegraph apparatus July 26th, 1871 Number 12400 Telegraphic recording instruments August 12th, 1871 Number 121601 Machinery for perforating paper for telegraph purposes August 16th, 1871 Number 126535 Printing telegraphs November 13th, 1871 Number 133841 Typewriting machine November 13th, 1871 1872 Number 126532 Printing telegraphs January 3rd, 1872 Number 126531 Printing telegraphs January 17th, 1872 Number 126534 Printing telegraphs January 17th, 1872 Number 126528 Type wheels for printing telegraphs January 23rd, 1872 Number 126529 Type wheels for printing telegraphs January 23rd, 1872 Number 126530 Printing telegraphs February 14th, 1872 Number 126533 Printing telegraphs February 14th, 1872 Number 132456 Apparatus for perforating paper for telegraphic use March 15th, 1872 Number 132455 Improvement in paper for chemical telegraphs April 10th, 1872 Number 133019 Electrical printing machine April 18th, 1872 Number 128131 Printing telegraphs April 26th, 1872 Number 128604 Printing telegraphs April 26th, 1872 Number 128605 Printing telegraphs April 26th, 1872 Number 128606 Printing telegraphs April 26, 1872 No. 128607 – Printing Telegraphs April 26, 1872 No. 131334 – Reotomes or Circuit Directors May 6, 1872 No. 134867 – Automatic Telegraph Instruments May 8, 1872 No. 134868 – Electromagnetic Adjusters May 8, 1872 No. 130795 – Electromagnets May 9, 1872 No. 131342 – Printing Telegraphs May 9, 1872 No. 131341 – Printing Telegraphs May 28, 1872 No. 131337 – Printing Telegraphs June 10, 1872 No. 131340 – Printing Telegraphs June 10, 1872 No. 131343 – Transmitters and Circuits for Printing Telegraph June 10, 1872 No. 131335 – Printing Telegraphs June 15, 1872 No. 131336 – Printing Telegraphs June 15, 1872 No. 131338 – Printing Telegraphs June 29, 1872 No. 131339 – Printing Telegraphs Telegraphs, June 29, 1872. Number 131344, Unison stops for printing Telegraphs, June 29, 1872. Number 134866, Printing and Telegraph Instruments, October 16, 1872. Number 138869, Printing Telegraphs, October 16, 1872. Number 142999, Galvanic Batteries, October 31, 1872. Number 141772, Automatic or Chemical Telegraphs, November 5, 1872. Number 135531, Circuits for Chemical Telegraphs, November 9, 1872. Number 146812, Telegraph Signal Boxes, November 26, 1872. Number 141773, Circuits for Automatic Telegraphs, December 12, 1872. Number 141776, Circuits for Automatic Telegraphs, December 12, 1872. Number 150848, Chemical or Automatic Telegraphs, December 12, 1872. 1873. Number 139128, Printing Telegraphs, January 21, 1873. Number 139129, Printing Telegraphs, February 13, 1873. Number 140487, Printing Telegraphs, February 13, 1873. Number 140489, Printing Telegraphs, February 13, 1873. Number 138870, Printing Telegraphs, March 7, 1873. Number 141774, Chemical Telegraphs, March 7, 1873. Number 141775, Perforator for Automatic Telegraphs, March 7, 1873. Number 141777, Relay Magnets, March 7, 1873. Number 142688, Electric Regulators for Transmitting Instruments, March 7, 1873. Number 156843, Duplex Chemical Telegraphs, March 7, 1873. Number 147312, Perforators for Automatic Telegraphy, March 24, 1873. Number 147314, Circuits for Chemical Telegraphs, March 24, 1873. Number 150847, Receiving Instruments for Chemical Telegraphs, March 24, 1873. Number 14088, Printing Telegraphs, April 23, 1873. Number 147311, Electric Telegraphs, April 23, 1873. Number 147313, Chemical Telegraphs, April 23, 1873. Number 147917, Duplex Telegraphs, April 23, 1873. Number 150846, Telegraph Relays, April 23, 1873. Number 160405, Adjustable Electromagnets for Relays, etc. April 23, 1873. Number 162633, Duplex Telegraphs, April 22, 1873. Number 151209, Automatic Telegraphy and Perforators Therefore, August 25, 1873. Number 160402, Solutions for Chemical Telegraph Paper, September 29, 1873. Number 160404, Solutions for Chemical Telegraph Paper, September 29, 1873. Number 160580, Solutions for Chemical Telegraph Paper, October 14, 1873. Number 160403, Solutions for Chemical Telegraph Paper, October 29, 1873. 1874, Number 154788, District Telegraph Signal Box, April 2, 1874. Number 168004, Printing Telegraph, May 22, 1874. Number 16659, Chemical Telegraphy, June 1, 1874. Number 166860, Chemical Telegraphy, June 1, 1874. Number 166861, Chemical Telegraphy, June 1, 1874. Number 158787, Telegraph Apparatus, August 7, 1874. Number 172305, Automatic Roman Character Telegraph, August 7, 1874. Number 173718, Automatic Telegraphy, August 7, 1874. Number 178221, Duplex Telegraphs, August 19, 1874. Number 178222, Duplex Telegraphs, August 19, 1874. Number 178223, Duplex Telegraphs, August 19, 1874. Number 180858, Duplex Telegraphs, August 19, 1874. Number 207723, Duplex Telegraphs, August 19, 1874. Number 480567, Duplex Telegraphs, August 19, 1874. Number 207724, Duplex Telegraphs, December 14, 1874. 1875, Number 168242, Transmitter and Receiver for Automatic Telegraph, January 18, 1875. Number 168243, Automatic Telegraphs, January 18, 1875. Number 168385, Duplex Telegraphs, January 18, 1875. Number 168466, Solution for Chemical Telegraphs, January 18, 1875. Number 168467, Recording Point for Chemical Telegraph, January 18, 1875. Number 195751, Automatic Telegraphs, January 18, 1875. Number 195752, Automatic Telegraphs, January 19, 1875. Number 171273, Telegraph Apparatus, February 11, 1875. Number 169972, Electric Signaling Instrument, February 24, 1875. Number 209241, Quadruplex Telegraph Repeaters, Reissued September 23, 1879. Number 8906, February 24, 1875. Number 1876, Number 180857, Autographic Printing, March 7, 1876. Number 198088, Telephonic Telegraphs, April 3, 1876. Number 198089, Telephonic or Electro-Harmonic Telegraphs, April 3, 1876. Number 182996, Acoustic Telegraphs, May 9, 1876. Number 186330, Acoustic Electric Telegraphs, May 9, 1876. Number 186548, Telegraph Alarm and Signal Apparatus, May 9, 1876. Number 198087, Telephonic Telegraphs, May 9, 1876. Number 185507, Electro-Harmonic Multiplex Telegraph, August 16, 1876. Number 2000993, Acoustic Telegraph, August 26, 1876. Number 235142, Acoustic Telegraph, August 26, 1876. Number 200032, Synchronous Movements for Electric Telegraphs, October 30, 1876. Number 2000994, Automatic Telegraph Perforator and Transmitter, October 30, 1876. Number 205370, Pneumatic Stencil Pens, February 3, 1877. Number 213554, Automatic Telegraphs, February 3, 1877. Number 196747, Stencil Pens, April 18, 1877. Number 203329, Perforating Pens, April 18, 1877. Number 474230, Speaking Telegraph, April 18, 1877. Number 217781, Sex Tuplex Telegraph, May 8, 1877. Number 230621, Addressing Machine, May 8, 1877. Number 377374, Telegraphy, May 8, 1877. Number 453601, Sex Tuplex Telegraph, May 31, 1877. Number 452913, Sex Tuplex Telegraph, May 31, 1877. Number 512872, Sex Tuplex Telegraph, May 31, 1877. Number 474231, Speaking Telegraph, July 9, 1877. Number 203014, Speaking Telegraph, July 16, 1877. Number 208299, Speaking Telegraph, July 16, 1877. Number 203015, Speaking Telegraph, August 16, 1877. Number 420594, Quadruplex Telegraph, August 16, 1877. Number 492789, Speaking Telegraph, August 31, 1877. Number 203013, Speaking Telegraph, December 8, 1877. Number 203018, Telephone or Speaking Telegraph, December 8, 1877. Number 200521, Phonograph or Speaking Machine, December 15, 1877. Number 203019, Circuit for Acoustic or Telephonic Telegraphs, February 13, 1878. Number 201760, Speaking Machines, February 28, 1878. Number 203016, Speaking Machines, February 28, 1878. Number 203017, Telephone Call Signals, February 28, 1878. Number 214636, Electric Lights, October 5, 1878. Number 222390, Carbon Telephones, November 8, 1878. Number 217782, Duplex Telegraphs, November 11, 1878. Number 214637, Thermal Regulator for Electric Lights, November 14, 1878. Number 210767, Vocal Engines, August 31, 1878. Number 218166, Magneto Electric Machines, December 3, 1878. Number 218866, Electric Lighting Apparatus, December 3, 1878. Number 219628, Electric Lights, December 3, 1878. Number 295990, Typewriter, December 4, 1878. Number 218167, Electric Lights, December 31, 1878. 1879, Number 224329, Electric Lighting Apparatus, January 23, 1879. Number 227229, Electric Lights, January 28, 1879. Number 227227, Electric Lights, February 6, 1879. Number 224665, Automatic Stencils for Printing, March 10, 1879. Number 227679, Phonograph, March 19, 1879. Number 221957, Telephone, March 24, 1879. Number 227229, Electric Lights, April 12, 1879. Number 264643, Magneto Electric Machines, April 21, 1879. Number 219393, Dynamo Electric Machines, July 7, 1879. Number 231704, Electrochemical Receiving Telephone, July 17, 1879. Number 266022, Telephone, August 1, 1879. Number 252442, Telephone, August 4, 1879. Number 222881, Magneto Electric Machines, September 4, 1879. Number 223898, Electric Lamp, November 1, 1879. 1880, Number 230255, Electric Lamps, January 28, 1880. Number 248425, Apparatus for Producing High Vacuums, January 28, 1880. Number 265311, Electric Lamp and Holder for Same, January 28, 1880. Number 369280, System of Electrical Distribution, January 28, 1880. Number 227226, Safety Conductor for Electric Lights, March 10, 1880. Number 228617, Brake for Electromagnetic Motors, March 10, 1880. Number 251545, Electric Meter, March 10, 1880. Number 525888, Manufacture of Carbons for Electric Lamps, March 10, 1880. Number 264649, Dynamo or Magneto Electric Machines, March 11, 1880. Number 228329, Magnetic or Separator, April 3, 1880. Number 238868, Manufacture of Carbons for Incandescent Electric Lamps, April 25, 1880. Number 237732, Electric Light, June 15, 1880. Number 24847, Manufacturing Carbons for Electric Lights, June 15, 1880. Number 298679, Treating Carbons for Electric Lights, June 15, 1880. Number 248430, Electromagnetic Brake, July 2, 1880. Number 265778, Electromagnetic Railway Engine, July 3, 1880. Number 248432, Magnetic Separator, July 26, 1880. Number 239150, Electric Lamp, July 27, 1880. Number 239372, Testing Electric Light Carbons, Edison and Bachelor, July 28, 1880. Number 251540, Carbon Electric Lamps, July 28, 1880. Number 263139, Manufacture of Carbons for Electric Lamps, July 28, 1880. Number 434585, Telegraph Relay, July 29, 1880. Number 248423, Carbonizer, July 30, 1880. Number 263140, Dynamo Electric Machines, July 30, 1880. Number 248434, Governor for Electric Engines, July 31, 1880. Number 239147, System of Electric Lighting, July 31, 1880. Number 264642, Electric Distribution and Translation System, August 4, 1880. Number 293433, Insulation of Railroad Tracks Used for Electric Circuits, August 6, 1880. Number 239373, Electric Lamp, August 7, 1880. Number 239745, Electric Lamp, August 7, 1880. Number 263135, Electric Lamp, August 7, 1880. Number 251546, Electric Lamp, August 10, 1880. Number 239153, Electric Lamp, August 11, 1880. Number 351855, Electric Lamp, August 11, 1880. Number 248435, Utilizing Electricity as Motive Power, August 12, 1880. Number 263132, Electromagnetic Roller, August 14, 1880. Number 264645, System of Conductors for the Distribution of Electricity. September 1, 1880. Number 240678, Webber Meter, September 22, 1880. Number 239152, System of Electric Lighting, October 14, 1880. Number 239148, Treating Carbons for Electric Lights, October 15, 1880. Number 238098, Magneto Signaling Apparatus, Edison and Johnson, October 21, 1880. Number 242900, Manufacturing Carbons for Electric Lamps, October 21, 1880. Number 251556, Regulator for Magneto or Dynamo Electric Machines, October 21, 1880. Number 248426, Apparatus for Treating Carbons for Electric Lamps, November 5, 1880. Number 239151, Forming Enlarged Ends on Carbon Filaments, November 19, 1880. Number 12631, Design Patent, Incandescent Electric Lamp, November 23, 1880. Number 239149, Incandescent Electric Lamp, December 3, 1880. Number 24296, Incandescent Electric Lamp, December 3, 1880. Number 24297, Incandescent Electric Lamp, December 3, 1880. Number 248565, Webber Meter, December 3, 1880. Number 263878, Electric Lamp, December 3, 1880. Number 239154, Relay for Telegraphs, December 11, 1880. Number 242898, Dynamo Electric Machine, December 11, 1880. Number 248431, Preserving Fruit, December 11, 1880. Number 265777, Treating Carbons for Electric Lamps, December 11, 1880. Number 239374, Regulating the Generation of Electric Currents, December 16, 1880. Number 248428, Manufacture of Incandescent Electric Lamps, December 16, 1880. Number 248427, Apparatus for Treating Carbons for Electric Lamps, December 21, 1880. Number 248437, Apparatus for Treating Carbons for Electric Lamps, December 21, 1880. Number 248416, Manufacture of Carbons for Electric Lights, December 30, 1880. Number 242899, Electric Lighting, January 19, 1881. Number 248418, Electric Lamp, January 19, 1881. Number 248433, Vacuum Apparatus, January 19, 1881. Number 251548, Incandescent Electric Lamps, January 19, 1881. Number 406824, Electric Meter, January 19, 1881. Number 248422, System of Electric Lighting, January 20, 1881. Number 431, 018, Dynamo or Magneto Electric Machine, February 3, 1881. Number 242901, Electric Motor, February 24, 1881. Number 248429, Electric Motor, February 24, 1881. Number 248421, Current Regulator for Dynamo Electric Machine, February 25, 1881. Number 251550, Magneto or Dynamo Electric Machines, February 26, 1881. Number 251555, Regulator for Dynamo Electric Machines, February 26, 1881. Number 482549, Means for Controlling Electric Generation, March 2, 1881. Number 248420, Fixture and Attachment for Electric Lamps, March 7, 1881. Number 251553, Electric Chandeliers, March 7, 1881. Number 251554, Electric Lamp and Socket or Holder, March 7, 1881. Number 248424, Fitting and Fixtures for Electric Lamps, March 8, 1881. Number 248419, Electric Lamp, March 30, 1881. Number 251542, System of Electric Light, April 19, 1881. Number 263145, Making Incandescence, April 19, 1881. Number 266447, Electric Incandescent Lamp, April 21, 1881. Number 266447, Electric Incandescent Lamp, April 21, 1881. Number 251552, Underground Conductors, April 22, 1881. Number 476531, Electric Lighting System, April 22, 1881. Number 248436, Depositing Cell for Plating the Connections of Electric Lamps, May 17, 1881. Number 251539, Electric Lamp, May 17, 1881. Number 263136, Regulator for Dynamo or Magneto Electric Machine, May 17, 1871. Number 251557, Webber Meter, May 19, 1881. Number 263134, Regulator for Magneto Electric Machine, May 19, 1881. Number 251541, Electromagnetic Motor, May 20, 1881. Number 251544, Manufacturer of Electric Lamps, May 20, 1881. Number 251549, Electric Lamp and the Manufacturer thereof, May 20, 1881. Number 251558, Webber Meter, May 20, 1881. Number 341644, Incandescent Electric Lamp, May 20, 1881. Number 251551, System of Electric Lighting, May 21, 1881. Number 263137, Electric Chandelier, May 21, 1881. Number 263141, Straightening Carbon for Incandescent Lamps, May 21, 1881. Number 264657, Incandescent Electric Lamps, May 21, 1881. Number 251543, Electric Lamp, May 24, 1881. Number 251538, Electric Light, May 27, 1881. Number 425760, Measurement of Electricity in Distribution System, May 31, 1881. Number 251547, Electrical Governor, June 2, 1881. Number 263150, Magneto or Dynamo Electric Machines, June 3, 1881. Number 263131, Magneto or Separator, June 4, 1881. Number 435687, Means for Charging and Using Secondary Batteries, June 21, 1881. Number 263143, Magneto or Dynamo Electric Machines, June 24, 1881. Number 251537, Dynamo Electric Machine, June 25, 1881. Number 263147, Vacuum Apparatus, July 1, 1881. Number 439389, Electric Lighting System, July 1, 1881. Number 263149, Commutator for Dynamo or Magneto Electric Machines, July 22, 1881. Number 479184, Facimally Telegraph Edison and Kenny, July 26, 1881. Number 400317 or Separator, August 11, 1881. Number 425763, Commutator for Dynamo Electric Machines, August 20, 1881. Number 263133, Dynamo or Magneto Electric Machine, August 24, 1881. Number 263142, Electrical Distribution System, August 24, 1881. Number 264647, Dynamo or Magneto Electric Machines, August 24, 1881. Number 404902, Electrical Distribution System, August 24, 1881. Number 257677, Telephone, September 7, 1881. Number 2666021, Telephone, September 7, 1881. Number 263144, Mold for Carbonizing Incandescence, September 19, 1881. Number 265774, Maintaining Temperatures in Webber meters, September 21, 1881. Number 264648, Dynamo or Magneto Electric Machines, September 23, 1881. Number 265776, Electric Lighting System, September 27, 1881. Number 524136, Regulator for Dynamo Electric Machines, September 27, 1881. Number 273715, Malleable Lizing Iron, October 4, 1881. Number 281352, Webber meter, October 5, 1881. Number 446667, Locomotives for Electric Railways, October 11, 1881. Number 288318, Regulator for Dynamo or Magneto Electric Machines, October 17, 1881. Number 263148, Dynamo or Magneto Electric Machines, October 25, 1881. Number 264646, Dynamo or Magneto Electric Machines, October 25, 1881. Number 251559, Electrical Drop Light, October 25, 1881. Number 266793, Electric Distribution System, October 25, 1881. Number 358599, Incandescent Electric Lamp, October 29, 1881. Number 264673, Regulator for Dynamo Electric Machines, November 3, 1881. Number 263138, Electric Arclight, November 7, 1881. Number 265775, Electric Arclight, November 7, 1881. Number 297580, Electric Arclight, November 7, 1881. Number 263146, Dynamo Magneto Electric Machines, November 22, 1881. Number 266588, Vacuum Apparatus, November 25, 1881. Number 251536, Vacuum Pump, December 5, 1881. Number 264650, Manufacturing Incandescent Electric Lamps, December 5, 1881. Number 264660, Regulator for Dynamo Electric Machines, December 5, 1881. Number 379770, Incandescent Electric Lamp, December 5, 1881. Number 293434, Incandescent Electric Lamp, December 5, 1881. Number 439391, Junction Box for Electric Wires, December 5, 1881. Number 454558, Incandescent Electric Lamp, December 5, 1881. Number 264653, Incandescent Electric Lamp, December 13, 1881. Number 358600, Incandescent Electric Lamp, December 13, 1881. Number 264652, Incandescent Electric Lamp, December 15, 1881. Number 278419, Dynamo Electric Machines, December 15, 1881. 1882. Number 265779, Regulator for Dynamo Electric Machines, January 17, 1882. Number 264654, Incandescent Electric Lamps, February 10, 1882. Number 264661, Regulator for Dynamo Electric Machines, February 10, 1882. Number 264664, Regulator for Dynamo Electric Machines, February 10, 1882. Number 264668, Regulator for Dynamo Electric Machines, February 10, 1882. Number 264669, Regulator for Dynamo Electric Machines, February 10, 1882. Number 264671, Regulator for Dynamo Electric Machines, February 10, 1882. Number 275613, Incandescent Electric Lamp, February 10, 1882. Number 401646, Incandescent Electric Lamp, February 10, 1882. Number 264658, Regulator for Dynamo Electric Machines, February 28, 1882. Number 264659, Regulator for Dynamo Electric Machines, February 28, 1882. Number 265780, Regulator for Dynamo Electric Machines, February 28, 1882. Number 265781, Regulator for Dynamo Electric Machines, February 28, 1882. Number 278416, Manufacturer of Incandescent Electric Lamps, February 28, 1882. Number 379771, Regulator for Dynamo Electric Machines, February 28, 1882. Number 272034, Telephone, March 30, 1882. Number 274576, Transmitting Telephone, March 30, 1882. Number 274577, Telephone, March 30, 1882. Number 264662, Regulators for Dynamo Electric Machines, May 1, 1882. Number 264663, Regulator for Dynamo Electric Machines, May 1, 1882. Number 264665, Regulator for Dynamo Electric Machines, May 1, 1882. Number 264666, Regulator for Dynamo Electric Machines, May 1, 1882. Number 268205, Dynamo or Magneto Electric Machine, May 1, 1882. Number 273488, 2488, regulator for dynamo-electric machines, May 1, 1882. Number 273492, secondary battery, May 19, 1882. Number 460122, process of an apparatus for generating electricity, May 19, 1882. Number 466460, electrolyte decomposition, May 19, 1882. Number 264672, regulator for dynamo-electric machines, May 22, 1882. Number 264667, regulator for dynamo-electric machines, May 22, 1882. Number 265786, apparatus for electrical transmission of power, May 22, 1882. Number 273828, system of underground conductors of electric distribution, May 22, 1882. Number 379772, system of electrical distribution, May 22, 1882. Number 274292, secondary battery, June 3, 1882. Number 281353, dynamo or magneto-electric machine, June 3, 1882. Number 287523, dynamo or magneto-electric machine, June 3, 1882. Number 365509, filament for incandescent electric lamps, June 3, 1882. Number 446668, electric arc light, June 3, 1882. Number 543985, incandescent conductor for electric lamps, June 3, 1882. Number 264651, incandescent electric lamps, June 9, 1882. Number 264655, incandescent electric lamps, June 9, 1882. Number 264670, regulator for dynamo-electric machines, June 9, 1882. Number 273489, turntable for electric railway, June 9, 1882. Number 273490, electromagnetic railway system, June 9, 1882. Number 40146, system of electric lighting, June 12, 1882. Number 476527, system of electric lighting, June 12, 1882. Number 439390, electric lighting system, June 19, 1882. Number 446666, system of electric lighting, June 19, 1882. Number 464822, system of distributing electricity, June 19, 1882. Number 304082, electrical meter, June 24, 1882. Number 274296, manufacturer of incandescence, July 5, 1882. Number 2646566, incandescent electric lamp, July 7, 1882. Number 265782, regulator for dynamo-electric machines, July 7, 1882. Number 265783, regulator for dynamo-electric machines, July 7, 1882. Number 265784, regulator for dynamo-electric machines, July 7, 1882. Number 265785, dynamo-electric machine, July 7, 1882. Number 273494, electrical railroad, July 7, 1882. Number 278418, translating electrical currents from high to low tension, July 7, 1882. Number 293435, electrical meter, July 7, 1882. Number 334853, mold for carbonizing, July 7, 1882. Number 339278, electric railway, July 7, 1882. Number 273714, magnetic electric signaling apparatus, August 5, 1882. Number 282287, magnetic electric signaling apparatus, August 5, 1882. Number 448778, electric railway, August 5, 1882. Number 439392, electric lighting system, August 12, 1882. Number 271613, manufacturer of incandescent electric lamps, August 25, 1882. Number 287518, manufacturer of incandescent electric lamps, August 25, 1882. Number 409825, electric meter, August 25, 1882. Number 439393, carbonizing chamber, August 25, 1882. Number 273487, regulator for dynamo-electric machines, September 12, 1882. Number 297581, incandescent electric lamp, September 12, 1882. Number 395962, manufacturing electric lamps, September 16, 1882. Number 287525, regulator for systems of electrical distribution, Edison and C. L. Clark, October 4, 1882. Number 365465, valve gear, October 5, 1882. Number 317631, incandescent electric lamp, October 7, 1882. Number 307029, filament for incandescent lamp, October 9, 1882. Number 268209, incandescent electric lamp, October 10, 1882. Number 273486, incandescent electric lamp, October 12, 1882. Number 274293, electric lamp, October 14, 1882. Number 275612, manufacturer of incandescent electric lamps, October 14, 1882. Number 430932, manufacturer of incandescent electric lamps, October 14, 1882. Number 271616, regulator for dynamo-electric machines, October 16, 1882. Number 543986, process for treating products derived from vegetable fibers, October 17, 1882. Number 543987, filament for incandescent lamps, October 17, 1882. Number 271614, shafting, October 19, 1882. Number 271615, governor for dynamo-electric machines, October 19, 1882. Number 273491, regulator for driving engines of electrical generators, October 19, 1882. Number 273493, valve gear for electrical generator engines, October 19, 1882. Number 41116, manufacturing carbon filaments, October 19, 1882. Number 492150, coding conductors for incandescent lamps, October 19, 1882. Number 273485, incandescent electric lamps, October 26, 1882. Number 317632, incandescent electric lamps, October 26, 1882. Number 317633, incandescent electric lamps, October 26, 1882. Number 287520, incandescent conductor for electric lamps, November 3, 1882. Number 353783, incandescent electric lamp, November 3, 1882. Number 430933, filament for incandescent lamps, November 3, 1882. Number 274294, incandescent electric lamp, November 13, 1882. Number 281350, regulator for dynamo-electric machines, November 13, 1882. Number 274295, incandescent electric lamp, November 14, 1882. Number 276233, electrical generator and motor, November 14, 1882. Number 274290, system of electrical distribution, November 20, 1882. Number 274291, mold for carbonizer, November 28, 1882. Number 278413, regulator for dynamo-electric machines, November 28, 1882. Number 278414, regulator for dynamo-electric machines, November 28, 1882. Number 287519, manufacturing incandescent electric lamps, November 28, 1882. Number 287524, regulator for dynamo-electric machines, November 28, 1882. Number 438298, Manufacture of Incandescent Electric Lamps, November 28, 1882. Number 276232, Operating and Regulating Electrical Generators, December 20, 1882. 1883. Number 278415, Manufacture of Incandescent Electric Lamps, January 13, 1883. Number 278417, Manufacture of Incandescent Electric Lamps, January 13, 1883. Number 281349, Regulator for Dynamo Electric Machines, January 13, 1883. Number 283985, System of Electrical Distribution, January 13, 1883. Number 283986, System of Electrical Distribution, January 13, 1883. Number 459835, Manufacture of Incandescent Electric Lamps, January 13, 1883. Number 13940, Design Patent, Incandescent Electric Lamps, February 13, 1883. Number 280727, System of Electrical Distribution, February 13, 1883. Number 359123, Circuit Controller for Dynamo Machine, February 13, 1883. Number 287521, Dynamo or Magneto Electric Machine, February 17, 1883. Number 287522, Mold for Carbonizing, February 17, 1883. Number 438299, Manufacture of Carbon Filaments, February 12, 1883. Number 446669, Manufacture of Filaments for Incandescent Electric Lamps, February 17, 1883. Number 476528, Incandescent Electric Lamp, February 17, 1883. Number 281351, Electrical Generator, March 5, 1883. Number 283984, System of Electrical Distribution, March 5, 1883. Number 287517, System of Electrical Distribution, March 14, 1883. Number 283983, System of Electrical Distribution, April 5, 1883. Number 354310, Manufacture of Carbon Conductors, April 6, 1883. Number 370123, Electric Meter, April 6, 1883. Number 41117, Carbonizing Flask, April 6, 1883. Number 370124, Manufacture of Filaments for Incandescent Electric Lamp, April 12, 1883. Number 287516, System of Electrical Distribution, May 8, 1883. Number 341839, Incandescent Electric Lamp, May 8, 1883. Number 398774, Incandescent Electric Lamp, May 8, 1883. Number 370125, Electrical Transmission of Power, June 1, 1883. Number 370126, Electrical Transmission of Power, June 1, 1883. Number 370127, Electrical Transmission of Power, June 1, 1883. Number 370128, Electrical Transmission of Power, June 1, 1883. Number 370129, Electrical Transmission of Power, June 1, 1883. Number 370130, Electrical Transmission of Power, June 1, 1883. Number 370131, Electrical Transmission of Power, June 1, 1883. Number 348300, gauge for testing fibers for incandescent lamp carbons, June 1, 1883. Number 287511, electric regulator, June 25, 1883. Number 287512, dynamoelectric machine, June 25, 1883. Number 287513, dynamoelectric machine, June 25, 1883. Number 287514, dynamoelectric machine, June 25, 1883. Number 287515, system of electrical distribution, June 25, 1883. Number 297582, dynamoelectric machine, June 25, 1883. Number 328572, commutator for dynamoelectric machines, June 25, 1883. Number 430934, electric lighting system, June 25, 1883. Number 438301, system of electric lighting, June 25, 1883. Number 297583, dynamoelectric machines, July 27, 1883. Number 304083, dynamoelectric machines, July 27, 1883. Number 304084, device for protecting electric light systems from lightning, July 27, 1883. Number 438302, commutator for dynamoelectric machine, July 27, 1883. Number 476529, system of electrical distribution, July 27, 1883. Number 297584, dynamoelectric machine, August 8, 1883. Number 307030, electrical meter, August 8, 1883. Number 297585, incandescent conductor for electric lamps, September 14, 1883. Number 297586, electrical conductor, September 14, 1883. Number 435688, process and apparatus for generating electricity, September 14, 1883. Number 470922, manufacturer of filaments for incandescent lamps, September 14, 1883. Number 490953, generating electricity, October 9, 1883. Number 293432, electrical generator or motor, October 17, 1883. Number 307031, electrical indicator, November 2, 1883. Number 337254, telephone, Edison and Bergman, November 10, 1883. Number 297587, dynamoelectric machine, November 16, 1883. Number 298954, dynamoelectric machine, November 15, 1883. Number 298955, dynamoelectric machine, November 15, 1883. Number 304085, system of electrical distribution, November 15, 1883. Number 509517, system of electrical distribution, November 15, 1883. Number 425761, incandescent lamp, November 20, 1883. Number 304086, incandescent electric lamp, December 15, 1883. Number 298956, operating dynamoelectric machine, January 5, 1884. Number 304087, electrical conductor, January 12, 1884. Number 395963, incandescent lamp filament, January 22, 1884. Number 526147, plating one material with another, January 22, 1884. Number 339279, system of electrical distribution, February 8, 1884. Number 314115, chemical stock quotation telegraph, Edison and Kenny, February 9, 1884. Number 436968, method and apparatus for drawing wire, June 2, 1884. Number 436969, apparatus for drawing wire, June 2, 1884. Number 438303, arc lamp, June 2, 1884. Number 343017, system of electrical distribution, June 27, 1884. Number 391595, system of electric lighting, July 16, 1884. Number 328573, system of electric lighting, September 12, 1884. Number 328574, system of electric lighting, September 12, 1884. Number 328575, system of electric lighting, September 12, 1884. Number 391596, incandescent electric lamp, September 24, 1884. Number 438304, electric signaling apparatus, September 24, 1884. Number 422577, apparatus for speaking telephones, Edison and Gilliland, October 21, 1884. Number 329030, telephone, December 3, 1884. Number 422578, telephone repeater, December 9, 1884. Number 422579, telephone repeater, December 9, 1884. Number 340707, telephonic repeater, December 9, 1884. Number 340708, electrical signaling apparatus, December 19, 1884. Number 347097, electrical signaling apparatus, December 19, 1884. Number 478743, telephone repeater, December 31, 1884.