Nikola Tesla – Elektro Motor Patent „Alternating Motor“ Original US Patent Lithograph No. 555,190 Submitted: May 15, 1888 Patented: February 25, 1896 Edition: 100 copies Each sheet, 27.5 x 17.5 cm This original US patent consists of one sheet of drawings and two sheets of description (pages 1 to 3). The drawing shows a schematic representation of an alternator connected to an electric motor (see the Figure 1) and a somewhat modified electric motor (see the Figure 2). The description starts with: Be it known that I, NIKOLA TESLA, a citizen of the United States, residing at New York, in the county and State of New York, have invented certain new and useful Improvements in Electromagnetic Motors,… NIKOLA TESLA (1856 - 1943) studied mathematics & physics at the Technical University of Graz/Austria, among others. His ideas and inventions created the basis for the modern alternating current network, electric motors, neon tubes, microwave ovens and the radio. This US patent specification is one of the early inventions on the AC motor. Extremely rare, especially due to the excellent condition. Provennienz: Birchmann Collection Edition and Rarity of US Patent Lithographs US Patent Lithographs are complete copies of the specifications and drawings of every US Patent issued. They contain of photo-lithographic drawing sheets which are single sided along with the full specification of the Patent on mostly double-sided sheets. Edition of US Patent Lithographs during the period 1871 to 1926 Beginning with July 1, 1871 one hundred and fifty copies of every US Patent issued were printed (1, see “first attempt”) and this edition was kept constant during the first two decades of reproduction. The edition was afterwards reduced to 100 copies since the fiscal year 1891 (7) and to 75 copies since the fiscal year 1899. After the year 1904 the edition was after all increased to 100 copies and kept constant until the end of the examined period (1926) (2) (3) (4) (5). Rarity of US Patent Lithographs Starting with July 1, 1871 the US Patent Lithographs were mainly distributed to the libraries around the country in so-called weekly bounded volumes and only a few of them were sold. Already one year later these weekly bounded volumes were substituted by monthly bounded Library Editions (July 1, 1872) because it was found that the fifty-two volumes per year fill up the shelves of the libraries so fast as to make the custody of the volumes somewhat irksome and expansive. The Library Editions also contain the full specifications and drawings of every US Patent, but printed on both sides of the page, the drawings, four on a page (6). Because the US Patent Lithographs failed almost wholly to supply the public want (1, see “supplemented by the Official Gazette”) they were additionally supplemented by the Official Gazette of the US Patent Office, instituted on May 18, 1872. Therefore, most US Patent Lithographs (especially within the first two or three decades of reproduction) remain in the US Patent Office after the midyear of 1872 and are of course already disposed. For example, in the report upon the damage of the fire from 1877 at the US Patent Office it was roughly estimated that the whole edition of 150 copies of every lost US Patent has been destroyed, about 40,000 sets or 600,000 copies at all (1, see “loss by fire”). Original US Patent Lithographs are thus extremely rare and only a handful of these Lithographs have certainly survived. Due to the fact that US Patent Lithographs before the fire from 1877 were printed by the American Photo-Lithographic Company until July, 1874 and by the Graphic Company of New York until June 30, 1875, respectively (1, see “American Photolithographic”), and thereafter by the Norris Peters Photo-Lithographer of Washington D.C. (also the reproductions of the lost sets), and because the particular Lithographer is marked at the bottom of the drawing sheet(s) in most cases, an original US Patent Lithograph before the fire from 1877 can be identified through the marked Lithographer in some extent. References: (1) Brief History of the United States Patent Office from its Foundation – 1790 to 1886 (2) Official Gazette of the United States Patent Office, Vol. 126, No. 5, January 29, 1907, pages 1779 and 1780 (3) Annual Report of the Commissioner of Patents for the Year 1915; Washington Government Printing Office 1916, page VII (4) Annual Report of the Commissioner of Patents for the Year 1922; Washington Government Printing Office 1923, page IX (5) Official Gazette of the United States Patent Office, Vol. 344, No. 3, March 16, 1926, pag