• Patent:GB107562 05.07.1917 Hemmi, Jiro : Improvements in the Slide Rules
• Patent:GB707804 04.05.1919 Ateliers Vaucanson :
• Patent:GB167699 16.01.1920 Darnley, Percey Henry and Richards, Barnett : Teaching arithmetic.-A device for facilitating the learning of multiplication and division
• Patent:GB139201 09.09.1920 Blaustein, Joseph : Improvements in calculating machines
• Patent:GB156715 07.01.1921 Rechnitzer, Alexander Autarit GMBH : Calculating-machine
• Patent:GB148455 10.01.1921 Kübler, Carl : Calculating Apparatus
• Patent:GB172909 12.01.1921 Kübler, Carl : Calculating Apparatus
• Patent:GB162895 12.05.1921 Bygrave, Leonard Charles Air Ministry Laboratory : Improvements in calculating apparatus
• Patent:GB150351 25.08.1921 Mang, Gerard & Fournier, Louis : Calculator
• Patent:GB183723 03.01.1922 King, Otis : Improvements in and relating to Calculating Apparatus
• Patent:GB148292 09.01.1922 Turck, Joseph Abraham Valentine Felt und Tarrant : Improvements in or connected with Calculating machines
• Patent:GB154603 27.03.1922 Turck, Joseph Abraham Valentine Felt und Tarrant :
• Patent:GB181043 06.06.1922 Felt und Tarrant : Improvements in Calculating Machines
• Patent:GB179933 14.09.1922 Augustin, Wilhelm Bing Werke : Improvement in or connecting with calculating machines
• Patent:GB192282 01.02.1923 Metcalfe, Robert Munkman : Planimeter
• Patent:GB175295 14.05.1923 Wolf, Ferdinand : Improvements in Planimeters
• Patent:GB183127 16.08.1923 Maschinenbau Fritz Koch Bing Werke : Improvements in or connecting with calculating machines
• Patent:GB207070 22.11.1923 Felt und Tarrant :
• Patent:GB231093 26.03.1925 Rosenthal, Louis & Messlang, Otto : Interlocking mechanism for calculating machines of the pin-wheel and cam-disc type
• Patent:GB259112 07.10.1926 Schauer, Joachim : Improvements in or relating to logarithmic calculating apparatus combined with writing implements
• Patent:GB270343 20.05.1927 Rechnitzer, Alexander Reder, Rudolf : An Improved Calculating Machine
• Patent:GB272569 07.06.1927 Gardner Calculator Company : Improvements in or relating to the Totalising Counters of Calculating Machines
• Patent:GB271935 06.03.1928 Thomas, Arthur Accounting & Tabulating Corp. : Statistical, calculating, and like machine controlled by mechanical records
• Patent:GB336997 23.10.1930 Original Odhner AB :
• Patent:GB341435 09.01.1931 Felt und Tarrant :
• Patent:GB342355 02.02.1931 Dall, Horace Edward & George Kent Ltd : Improvements in Planimeters
• Patent:GB357818 01.10.1931 Seemann, Rosa Aloisia : Improvements in Planimeters
• Patent:GB360375 02.11.1931 Petter, Guy Bazeley Petters Limited : Improvements in or relating to calculating or adding machines
• Patent:GB360376 02.11.1931 Petter, Guy Bazeley Petters Limited : Improvements in or relating to calculating or adding machines
• Patent:GB360377 02.11.1931 Petter, Guy Bazeley Petters Limited : Improvements in or relating to calculating or adding machines
• Patent:GB410129 09.05.1934 Valtat, Raymond Louis Andre : Improvements in or retlating to Calculating and like Apparatus
• Patent:GB411090 29.05.1934 Boardman, Hubert A.G. Thornton : Improvements in Slide Rule Calculators
• Patent:GB422344 07.01.1935 Baldwin, Richard Everest : Improvements in or relating to paper feeding mechanism for statistical and like machines
• Patent:GB437743 04.11.1935 Hamann, Christel Deutsche Telephonwerke und Kabelindustrie Aktiengesellschaft : Improvements in and relating to Calculating Machines
• Patent:GB443689 04.03.1936 Dussel, Cornelis Jan & Pasveer, Jan : Circular Slide Rule
• Patent:GB446338 27.04.1936 Broido, Daniel & Hausmann, Raoul (der Dadaist!) : Improvements in and relating to calculating apparatus
• Patent:GB448787 15.06.1936 Boutet, Louis Charles : Electric calculating machine
• Patent:GB448925 15.06.1936 Boutet, Louis Charles : Electric calculating machine
• Patent:GB454857 05.10.1936 Baldwin, Richard Everest : Improvements in and relating to printing mechanism for calculating machines
• Patent:GB468257 01.07.1937 Boardman, Hubert & Clayton, Albert Edmund & Naylor, Felix Samuel Thornton Ltd : Improvements in Slide Rule calculators, other scale devices, and direction drawing instruments
• Patent:GB514289 03.11.1939 Webb, Christopher Frederick : Improvements in or relating to calculating or adding machines
• Patent:GB514290 03.11.1939 Webb, Christopher Frederick : Improvements relating to calculating machines
• Patent:GB514291 03.11.1939 Webb, Christopher Frederick : Improvements relating to calculating machines
• Patent:GB516535 04.01.1940 Webb, Christopher Frederick : comptometer-like adding machine
• Patent:GB516557 04.01.1940 Webb, Christopher Frederick : comptometer-like adding machine
• Patent:GB522721 25.06.1940 Webb, Christopher Frederick : comptometer-like adding machine
• Patent:GB535478 10.04.1941 Nicolls, Wilfred, Evans, Fraser Mackie C.A.V. Limited : locking device
• Patent:GB551707 05.03.1943 Felt und Tarrant : Improvements in or relating to numeral wheels or the like
• Patent:GB551994 18.03.1943 Felt und Tarrant :
• Patent:GB553198 12.05.1943 Felt und Tarrant :
• Patent:GB556239 27.09.1943 Felt und Tarrant :
• Patent:GB616253 19.01.1949 Kern und Co Ltd : Planimeter
• Patent:GB616254 19.01.1949 Kern und Co Ltd : Planimeter with an optical reading-off device
• Patent:GB640347 19.07.1950 Felt und Tarrant :
• Patent:GB640445 19.07.1950 Felt und Tarrant :
• Patent:GB644944 18.10.1950 Manyweathers, Leslie Blundell Rules Ltd : Slide Rule
• Patent:GB650728 28.02.1951 Felt und Tarrant :
• Patent:GB652626 25.04.1951 Webb, Christopher Frederick Bell Punch Co Ltd : Improvements in or relating to Calculating Machines.
• Patent:GB652627 25.04.1951 Webb, Christopher Frederick Bell Punch Co Ltd : Improvements in or relating to Calculating Machines.
• Patent:GB652670 25.04.1951 Webb, Christopher Frederick Bell Punch Co Ltd : comptometer-like adding machine
• Patent:GB709026 12.05.1954 Green, George Wilfrid Acland : Slide Rule for spring calculations
• Patent:GB773099 29.04.1955 Lehre, Otto Sterling : Calculating-apparatus (Sterling Dial-A-Matic)
• Patent:GB740826 23.11.1955 Fuller, John Rodney Dyson Bristol Aeroplane Co Ltd : Improvements in or relating to Planimeters and like mechanical integrating apparatus
• Patent:GB749134 16.05.1956 Etablissements Japy Freres : Improvements relating to Adding Machines Adapted for Multiplication and Division
• Patent:GB752054 04.07.1956 Ott, Hermann : Mounting for the measuring roller of Planimeters or the like
• Patent:GB778078 03.07.1957 Aktiebolaget Original-Odhner : Improvements in adding machines and like calculating machines
• Patent:GB801843 24.09.1958 Ott, Hermann : Measuring roller for Planimeters
• Patent:GB831200 23.03.1960 Taylor, Jack British Thomson Houston Co Ltd : Improvements relating to the measurement of small areas
• Patent:GB838237 22.06.1960 Adegboye Akinwunmi : An instrument for measuring areas
• Patent:GB984279 24.02.1965 Aktiebolaget Original-Odhner : Registers for Adding Machines, Book-Keeping Machines and other Calculating Machines
• Patent:GB992094 12.05.1965 Babel, Michael : Planimeter
• Patent:GB1035188 06.07.1966 Dennert, Georg und Dennert, Hans Dennert und Pape : Stand for Slide Rule
• Patent:GB1039127 17.08.1966 Müller, Friedrich Dennert und Pape : Slide Rule Cursor
• Patent:GB1065482 19.01.1967 Dennert, Hans, Dennert, Georg Dennert und Pape : Scale reading magnifier

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