Instrument

Instruments might be useful for the purpose of navigating through the air, or for external interests such as collecting meteorological data.

Recording thermometer illustrated in 1898

"Universal meteograph" comprising themometer, barometer, and psychrometer.

Many instruments at the turn of the century can be obtained as appareils enregistreurs (i.e., recording apparatuses) with interior compartments in which a needle continuously imprints the data on a scroll.

Enclosing categories	Simple tech terms
Subcategories	Compass, Barometer, accelerometer, Thermometer, psychrometer
Keywords	Navigation, Photography, Meteorology
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Patents in categories Instrument or Instrument

• Patent BE-1912-12-11 Eugène-Pierre-Félix-Auguste Coursin (English title: (title not presently unavailable), Inventors: Eugène-Pierre-Félix-Auguste Coursin)
• Patent IT-1908-97752 (English title: Air current indicator for balloons and other aircraft, Inventors: Charles Davis)
• Patent ES-1907-41781 (English title: Improvements in aerial photographic devices, Inventors: George Raymond Lawrence)
• Patent GB-1885-339 (Inventors: J. G. Lorrain)
• Patent GB-1897-12146 (English title: Kite, Inventors: Henry Helm Clayton)
• Patent GB-1913-27584 (English title: An Improved Method of and Means for Range-finding from Aerial Craft, Inventors: Henri-Marie Coandă • John Herschel Hardcastle)
• Patent BE-1914-266541 (English title: Apparatus for indicating the ascent and descent of balloons, Inventors: H. Apelt)
• Patent BE-1914-266010 (English title: Indicating device for airplanes, Inventors: Henri-Pierre Rouet)
• Patent FR-1893-232001 (English title: System facilitating the recognition, in the context of thick sea fog, the direction from which perceived sounds come, Inventors: Duchâteau)
• Patent FR-1895-244139 (English title: Isohypse, Inventors: Ebray)
• Patent FR-1850-10692 (English title: Aerostat system, Inventors: Pierre-Célestin Arnault • Pierre Jullien)
• Patent US-1876-182172 (English title: Apparatus for indicating the intensity of radiation, Inventors: William Crookes)
• Patent FR-1880-135768 (English title: Control compass with a built-in, or connected dromoscope, Inventors: Peichl)
• Patent US-1883-291990 (English title: Balloon-propeller, Inventors: Kansas D. Davis)
• Patent US-1889-399783 (English title: Airship, Inventors: Herman A. J. Rieckert)
• Patent FR-1893-232924 (English title: Electric indicator display of rudder movements, Inventors: Calten)
• Patent FR-1893-234707 (English title: new use of electricity in all apparatus of aerial navigation, Inventors: Le Clément de Saint-Marcq)
• Patent FR-1893-231837 (English title: Apparatus connected to a compass so as to form electric currents which serve to regulate the dynamic motor of the rudder and to make function an apparatus of control indicating and registering route deviations, Inventors: Langen)
• Patent GB-1895-25050 (English title: Automatically controlled vertical and horizontal rudders, Inventors: Edward Joel Pennington)
• Patent FR-1896-258328 (English title: Sonic direction-finder, air or water, Inventors: Hardy)
• Patent FR-1896-256405 (English title: System for mounting recording cylinders in measuring instruments, Inventors: Boileau)
• Patent FR-1896-255978 (English title: Temperature alert, Inventors: Fischer)
• Patent FR-1896-253293 (English title: recording barometer, Inventors: HUE)
• Patent DE-1897-95179 (English title: Apparatus for maintaining iarships at a certain height by means of barometer, Inventors: Edward Joel Pennington)
• Patent GB-1896-9142 (English title: Aeronautical Ships, Inventors: Edward Joel Pennington)
• Patent GB-1896-11995 (English title: Aerial Navigation, Inventors: Edward Joel Pennington)
• Patent FR-1897-268680 (English title: electrical order transmitter, Inventors: Brillie)
• Patent FR-1898-283981 (English title: instrument read-out, Inventors: Krahenbuhl)
• Patent FR-1898-280741 (English title: Leveling magnetic compass, Inventors: Louis Souchier)
• Patent FR-1898-281425 (English title: Improvements to the maxima thermometer, Inventors: Simpson Heinitz)
• Patent FR-1898-281990 (English title: Chronometer with display, Inventors: Marfaing)
• Patent FR-1898-274981 (English title: improvements to electric signal transmission, Inventors: Léopold)
• Patent FR-1898-274674 (English title: Improved portable barometer, Inventors: Gustave Hermite)
• Patent FR-1898-276663 (English title: Automatic stop-trigger for measuring or recording instruments, Inventors: Hein)
• Patent FR-1899-295364 (English title: Telescope, Inventors: Gars)
• Patent FR-1899-289654 (English title: Pocket compass, Inventors: Strauss)
• Patent FR-1899-289333 (English title: Pocket sundial with compass, Inventors: Dietrich)
• Patent FR-1899-285841 (English title: Improvements in aneroid barometers, Inventors: Watkin)
• Patent FR-1900-302174 (English title: Optical apparatus for lighting distant objects, Inventors: Engelsmann)
• Patent US-1900-651361 (English title: Electric telegraphy, Inventors: Isidor Kitsee)
• Patent DE-1901-134729 (English title: Gas pressure regulation apparatus, Inventors: Alexander Levy)
• Patent ES-1903-31918 (English title: "Telekine" system for controlling mechanical movement at a distance, Inventors: Leonardo Torres Quevedo)
• Patent FR-1902-327218 (English title: "Telekine" system for causing mechanical movement at a distance, Inventors: Leonardo Torres Quevedo)
• Patent US-1904-770024 (English title: Horn for phonographs or similar machines, Inventors: Bartolo Ruggiero • Gaetano Bongiorno)
• Patent US-1904-803573 (English title: Captive observation-balloon apparatus, Inventors: Reuben B. Eubank Jr)
• Patent FR-1906-360273 (English title: Regulator control, Inventors: Fritz Reichenbach)
• Patent US-1905-824616 (English title: Tailless kite which can be taken to pieces, Inventors: Alfred-Jacques Bergeron)
• Patent US-1907-859274 (English title: Flying machine, Inventors: John Holmes Wilson)
• Patent US-1906-863035 (English title: Device for maintaining instruments in adjusted positions, Inventors: Alfred Maul)
• Patent GB-1906-10758 (English title: A Device for the Safe Landing of Instruments or the like sent up into the Air, Inventors: Alfred Maul)
• Patent BE-1907-202697 (English title: Instruments of measuring and of weighing forces and apparatus air thinning or of compression of air layers, these apparatus reclosing in the circumlocution of the pilots who raise and sustain in the air, without supporting balloon strictly by the force of a motor mechanism of propulsion and lift-sus, Inventors: Alfred E. Wunderlich, Applicant firm: A. Wunderlich & Cie, Ingénieurs-Conseils)
• Patent US-1906-847198 (English title: Rocket apparatus, Inventors: Alfred Maul)
• Patent DE-1907-204239 (English title: Apparatus for specifying the navigational orientation of aircraft, Applicant firm: Siemens-Schuckert Werke GmbH)
• Patent FR-1908-386154 (English title: Instrument for measuring small changes in balloon altitude, Inventors: Pierre Chauvassaignes)
• Patent FR-1908-393597 (English title: Instrument for determining the direction of movement of air vehicles, Applicant firm: Siemens-Schuckert Werke GmbH)
• Patent AT-1909-41250 (English title: Device for displaying the decrease in pressure in air tubes of compressed air (or aviation tires) by means of electrical current, Inventors: Ludwig Schmidl)
• Patent CH-1907-42902 (English title: Medium-sized wind kite, aeroplan, balloon or the like to lift up equipment to keep the photographic cameras worn by it floating, Inventors: George Raymond Lawrence)
• Patent US-1909-923181 (English title: Kite-parachute, Inventors: Frank Ernest Jackson)
• Patent HU-1908-46110 (English title: Equipment for determining the direction of travel of airborne vehicles, Applicant firm: Siemens-Schuckert Werke GmbH)
• Patent FR-1908-401308.11387 (English title: Apparatus with gyroscopes for aerial navigation, Inventors: Hippolyte Chevron • Jacques Ravelli)
• Patent FR-1908-401308 (English title: gyroscopic apparatus for aerial navigation, Inventors: Hippolyte Chevron • Jacques Ravelli)
• Patent FR-1909-401488 (English title: Apparatus for measuring differences in gas pressure, Inventors: Herrmann Storrer)
• Patent FR-1910-407769 (English title: control apparatus applicable to aerostats and airplanes, Applicant firm: Établissements de Dion-Bouton)
• Patent FR-1910-411786 (English title: System of wings of independent angle of air attack, along with appropriate instruments of indication and means of control, Inventors: Louis-Isidore Henry)
• Patent HU-1908-49760 (English title: Equipment for determining the direction of travel of airborne vehicles, Applicant firm: Siemens-Schuckert Werke GmbH)
• Patent BE-1910-202697.224719 (English title: Instruments for measuring and weighing forces and devices for rarefaction or compression of air layers, carried by (?) the airmen who ascend or maintain altitude without a supporting balloon using only the force of a motor mechanism of propulsion and lift-sustentation, Inventors: Alfred E. Wunderlich, Applicant firm: A. Wunderlich & Cie, Ingénieurs-Conseils)
• Patent CA-1911-134092 (English title: Clinometer, Inventors: Ewald Müller)
• Patent AT-1911-51955 (English title: Apparatus for detecting upper fog or cloud boundaries using captive balloons or kites, Applicant firm: S. Saul Gummiwarenfabrik)
• Patent ES-1911-49932 (English title: A clinometer with signal apparatus for air navigation, Inventors: Ewald Müller)
• Patent FR-1911-424790 (English title: process for maintaining balloon gas temperature at a uniform average temperature, Inventors: A. W. Peust • W. Roeder)
• Patent LU-1911-8870 (English title: Clinometer with display for aeronautics, Inventors: E. Muller)
• Patent AT-1909-49255 (English title: Altitude control for flying machines, Inventors: Wilhelm Pega • Karl Emich)
• Patent FR-1911-425978 (English title: Compass indicating aerial route for airplanes, balloons, etc., Inventors: Joseph Lamant)
• Patent FR-1911-429102 (English title: Automatic compass specifically applicable to the airplane, Inventors: Honoré-Maurice Domecq-Cazaux)
• Patent GB-1910-20184 (Inventors: Allan John Grant)
• Patent US-1911-982336 (English title: Accelerometer, Inventors: Harry Egerton Wimperis)
• Patent FR-1911-434663 (English title: stabilizing device with automatic and required function, Inventors: Paul Huguet)
• Patent FR-1911-432053 (English title: Complete flying machine system, including multiple indicators and all means of control and propulsion, Inventors: Louis-Isidore Henry)
• Patent FR-1911-431380 (English title: Automatic fin (vertical?) indicator for aerial locomotion, Inventors: Pierre Poulalion • Jean Armange)
• Patent FR-1912-437863.15836 (English title: 1st certificate of addition, with the patent taken on December 18th, 1911, for device of aeronautic weapon sighting, Inventors: Eugène-Pierre-Félix-Auguste Coursin)
• Patent FR-1912-445914 (English title: Improvements to automatic adjustment apparatus for airplanes and airships, Inventors: Valentine Hall Mammatt)
• Patent FR-1912-433481 (English title: Apparatus of airplane wing control, along with instrument indicating said relative positioning, Inventors: Miklos Heini, Dénes Darvas)
• Patent HU-1911-55642 (English title: Inclinometer with signaling device for aeronautical purposes, Inventors: Ewald Müller)
• Patent GB-1911-24415 (English title: Inclinometer for aircraft, Inventors: John Perrin)
• Patent FR-1912-440087 (English title: Method and viewing apparatus for evaluating aircraft speed relative to the ground, Inventors: Angel-Félix Philiponeau • Marie-Joseph-Adrien-Maurice de Brisson de Laroche)
• Patent FR-1911-401308.15491 (English title: Gyroscope device for aerial navigation, Inventors: Hippolyte Chevron • Jacques Ravelli)
• Patent FR-1912-447535 (English title: Anemometer to indicate the speed of an airplane, Applicant firm: Ateliers d'aviation Louis Bréguet)
• Patent US-1911-1028502 (English title: Airplane sighting devices, Inventors: Frank Lee Slack)
• Patent GB-1911-16545 (English title: A Sighting Device for use on Aeroplanes or Dirigible Balloons, Inventors: Frank Lee Slack)
• Patent FR-1912-434663.15762 (English title: Stabilizer device with automatic and imperative operation, Inventors: Paul Huguet)
• Patent FR-1911-438363.15772 (English title: Device for automatic longitudinal equilibrium control and indicator for aircraft, Inventors: Adolphe-François-Joseph Doutre)
• Patent FR-1912-432053.16181 (English title: Further elaborations on a complete flying machine system, Inventors: Louis-Isidore Henry)
• Patent GB-1912-6818 (English title: Automatic Stabilisation of Aeroplanes and the like, Inventors: Louis Marmonier)
• Patent FR-1911-445813 (English title: System for launching a projectile at a specific point from an airplane or dirigible, Inventors: Auguste-Blaise Baron • Paul-Eugène Mesplès)
• Patent GB-1912-20941 (English title: Improvements in and relating to Aeroplanes, Inventors: Michael Rukawischnikoff)
• Patent AT-1911-54503 (English title: Compass, particularly for aircraft, Inventors: Adolf Warchalowski)
• Patent GB-1912-13867 (English title: Automatic fin (vertical?) indicator for aerial locomotion, Inventors: Pierre Poulalion • Jean Armange)
• Patent GB-1912-884 (English title: Device indicating the horizontal lean of an aerial machine during flight, Inventors: David Palmgren)
• Patent FR-1912-442088 (English title: Point compass for air travel, Inventors: Jules Leloup)
• Patent FR-1912-436529.16745 (English title: Apparatus for parachute activation, Inventors: Adolf Freiherr Odkolek von Augezd)
• Patent GB-1912-28836 (English title: Improvements in or relating to sighting apparatus for use on aerial machines, Inventors: Eugène-Pierre-Félix-Auguste Coursin)
• Patent FR-1913-457651 (English title: Propeller control system for propeller-driven vehicles (airplanes), Inventors: Auguste Ransy-Putzeys)
• Patent BE-1913-Auguste Ransey-Putzeys (English title: Propeller control system for propeller-driven vehicles (airplanes), Inventors: Auguste Ransey-Putzeys)
• Patent GB-1912-28596 (English title: Means for Indicating the Speed of Aircraft, Inventors: Harry Egerton Wimperis • George Keith Bulle Elphinstone)
• Patent FR-1913-432053.17603 (English title: Further elaborations on a complete flying machine system, Inventors: Louis-Isidore Henry)
• Patent FR-1912-450428 (English title: Improvements to automatic stabilizers for aeronautical machines based on the combined use of anemometer and accelerometer, Inventors: Jean-Baptiste-Émile Dorand)
• Patent DE-1913-268193 (English title: Device for measuring the speed of aircraft, Inventors: Wolfgang Kreuter • Otto E. Lindpaintner)
• Patent DE-1912-262746 (English title: Device for measuring the speed of aircraft, Inventors: Wolfgang Kreuter • Otto E. Lindpaintner)
• Patent FR-1913-431380.17358 (English title: Automatic fin (vertical?) indicator for aerial locomotion, Inventors: Pierre Poulalion • Jean Armange)
• Patent US-1910-1050573 (English title: Buoyancy-Indicator, Inventors: George A. Spratt)
• Patent GB-1913-28836E (English title: Improvements in or relating to sighting apparatus for use on aerial machines, Inventors: Eugène-Pierre-Félix-Auguste Coursin)
• Patent FR-1914-457651.19315 (English title: Blade system for control of vehicles propelled by aerial blades, Inventors: Auguste Ransy-Putzeys)
• Patent US-1912-1084831 (English title: Speed and Direction Indicator for Airships, Inventors: Melvin Vaniman)
• Patent FR-1912-450121 (English title: Improvements to illuminating devices for use in connection with airships, Inventors: Emil Hyra • Karl Klinkosch)
• Patent DE-1913-270303 (English title: Timed balloon vent, Applicant firm: Gummiwarenfabrik S. Saul)
• Patent FR-1913-465447 (English title: Aiming device for firing from aboard airships, Inventors: Eugène-Pierre-Félix-Auguste Coursin)
• Patent GB-1913-28229 (English title: An apparatus for aiming projectiles from airships, Inventors: Eugène-Pierre-Félix-Auguste Coursin)
• Patent FR-1914-469080 (English title: Improvements in automatic airplane stabilization, Inventors: Attila Pédery • Desiderius Varsányi • Aladar Zoltán)
• Patent US-1910-1121309 (English title: Course and Speed Indicating Device for Flying-Machines, Inventors: Robert M. Thompson)
• Patent FR-1914-450121.19096 (English title: Improvements to illuminating devices for use in connection with airships, Inventors: Emil Hyra • Karl Klinkosch)
• Patent US-1913-1123253 (English title: Speedometer for Aeroplanes and Other Aerial Devices, Inventors: Oscar Alvin Danielson)
• Patent DE-1914-286453 (English title: Switchboard for bomb dropping devices on airplanes, Inventors: Hermann M. Fremery)
• Patent DE-1911-288818 (English title: Device for correcting readings from a gyro-compass, Inventors: Elmer Ambrose Sperry)
• Patent FR-1914-475761 (English title: Improvements brought to flying machines, Inventors: Jules Gastambide • Robert Gastambide)
• Patent BE-1916-275652 (English title: Indicator of ascent and descent for aero, Inventors: N. Thiry)
• Patent DE-1915-289673 (English title: Speedometer for any kind of aircraft, Inventors: Oscar Alvin Danielson)
• Patent GB-1914-24634 (English title: Speedometer, Inventors: Oscar Alvin Danielson)
• Patent CA-1915-169201 (English title: Speedometer for Aeroplanes, Inventors: Oscar Alvin Danielson)
• Patent BE-1916-275625 (English title: Windspeed indicator for aero, Inventors: N. Thiry)
• Patent US-1910-1181851 (English title: ELECTRICAL INDICATOR FOR STREET-CARS, Inventors: Richard M. Craig)
• Patent DE-1917-300978 (English title: Indicator showing average pressure measurement from engine cylinders, Inventors: Emil Schimanek)
• Patent NL-1913-2447 (English title: Sighting device for projectile dropping devices of aircraft (in particular aircraft), Applicant firm: Friedrich Krupp Aktiengesellschaft)
• Patent HU-1917-73290 (English title: Counter to indicate flight time, Inventors: Andreas Veigel)
• Patent US-1914-1274622 (English title: Speed and Direction Indicator for Aircraft, Inventors: Elmer A. Sperry, Applicant firm: Sperry Gyroscope Company)
• Patent DE-1916-304615 (English title: Apparatus for recording the path of an aircraft with one device measuring forward motion, the other recording direction, Inventors: Hermann Burkardt)
• Patent DE-1917-304468 (English title: Navigational triangle for aircraft with direct compass display, Inventors: Hans Georg Bader)
• Patent DE-1913-304553 (English title: Device for astronomical place reckoning using clockwork, Inventors: Horace Seely Butterfield)
• Patent DE-1916-304450 (English title: Speedometer with intermittently active needle, Inventors: Heinrich Hornig)
• Patent DE-1916-304712 (English title: Compass, Inventors: Otto Schnetzer)
• Patent DE-1916-304554 (English title: Apparatus for determining the direction and location of aircraft, Inventors: Charles Daniel Woodward)
• Patent DE-1917-305339 (English title: Venturi meter for measuring the speed of gas flow, Inventors: Wilhelm Morell)
• Patent DE-1914-304614 (English title: Apparatus for reading true direction by gyro-compass, Inventors: Hannibal C. Ford • Harry L. Tanner, Applicant firm: Sperry Gyroscope Company)
• Patent DE-1917-305476 (English title: Indicator showing average pressure measurement from engine cylinders, Inventors: Emil Schimanek)
• Patent DE-1917-304552 (English title: Liquid compass, Applicant firm: Firma C. Plath)
• Patent US-1911-1279471 (English title: Gyroscopic Compass, Inventors: Elmer Ambrose Sperry)
• Patent DE-1915-306635 (English title: Method and apparatus for automatically reckoning the course deviation of airplanes and airships, Inventors: Melli Beese-Boutard)
• Patent DE-1917-305477 (English title: Indicator showing average pressure measurement from engine cylinders, Inventors: Emil Schimanek)
• Patent HU-1917-77280 (English title: Indicator measuring the average temperature prevailing in engine cylinders, Inventors: Emil Schimanek)
• Patent HU-1917-73345 (English title: Indicator measuring the average temperature prevailing in engine cylinders, Inventors: Emil Schimanek)
• Patent DE-1917-307530 (English title: Acute pressure gauge for measurement of small pressure differences for air-, water-, and land-craft., Applicant firm: Luftschiffbau Schütte-Lanz)
• Patent DE-1916-307534 (English title: Electrical remote speedometer with alternating current dynamo?, Applicant firm: Robert Bosch A.G.)
• Patent DE-1916-305717 (English title: Display for benzene tank, Inventors: Paul Borck • Heinrich Fitte)
• Patent NL-1917-4416 (English title: Device for determining the ascent and descent speed in air or water (said instrument either attached to the propeller or more likely operated by a propeller-or-responsive-fan of its own), Inventors: Dr. Cornelis Schoute • Floris Albert van Heyst • Nicolaas Everhard Groeneveld Meyer)
• Patent HU-1917-74697 (English title: Equipment for determining the current position of an aircraft in relation to the top of the ground, Applicant firm: Luftschiffbau Schütte-Lanz)
• Patent HU-1917-74856 (English title: Equipment for the indication of the influence of weight changes on airships on the equilibrium, Applicant firm: Luftschiffbau Schütte-Lanz)
• Patent US-1918-1315065 (English title: Aerial-Navigation Instrument, Inventors: Harry Egerton Wimperis)
• Patent GB-1918-131757 (English title: Apparatus for Determining Directions and Speeds, for use on Aircraft, Inventors: Harry Egerton Wimperis)
• Patent FR-1917-494247 (English title: Gasometer balloon for aeronautical or industrial uses, Applicant firm: Société Zodiac)
• Patent HU-1917-75560 (English title: Regulator for aircraft engine coolers, Inventors: Hans Windhoff)
• Patent GB-1915-14379 (English title: Improved Range-finder, Inventors: Henry Wilson-Fox)
• Patent GB-1915-13213 (English title: Improvements to Range-finders, Inventors: Henry Wilson Fox)
• Patent AT-1918-79790 (English title: Display device for the mode of action of the bomb release on aircraft, Applicant firm: Gothaer Waggonfabrik A. G.)
• Patent US-1918-1309489 (English title: Double-Gyro Inclinometer, Inventors: Lawrence Burst Sperry, Applicant firm: Sperry Gyroscope Company)
• Patent GB-1917-122426 (English title: Improvements in or relating to Apparatus for Indicating the Straightness or Curvature of the Course of Aircraft, Inventors: Jacques de Lesseps • Roger Courtois-Suffit)
• Patent GB-1917-135915 (English title: A Landing Indicator for Aerial Machines, Inventors: Roger Courtois-Suffit)
• Patent DE-1917-310675 (English title: Tilt and curve indicator for aircraft, Inventors: Georg von dem Borne, Applicant firm: Atmos • Atmos-Werkstätten)
• Patent DE-1918-316370 (English title: Tilt and curve indicator for aircraft, Inventors: Georg von dem Borne, Applicant firm: Atmos • Atmos-Werkstätten)
• Patent AT-1917-81135 (English title: Device to determine the height of a point above the earth from this point from the headlight and an optical instrument serving to observe the reflected rays, Inventors: Oscar Gerhardt)
• Patent GB-1917-129681 (English title: Controlling gear for aeroplanes, Inventors: Émile Letord)
• Patent NL-1917-4962 (English title: Apparatus for determining the position or movement of a body or for controlling auxiliary devices in dependence thereon, Inventors: Dr. Cornelis Schmoute • Floris Albert van Heyst • Nicolaas Everhard Groeneveld Meyer)
• Patent US-1914-1360694 (English title: Navigational Apparatus, Inventors: Elmer Ambrose Sperry, Applicant firm: Sperry Gyroscope Company)
• Patent HU-1917-76911 (English title: Apparatus for determining the altitude of a point by means of a headlamp and an optical instrument for the observation of reflected rays, Inventors: Oscar Gerhardt)
• Patent FR-1915-502395 (English title: Longitudinal and transverse slope indicator for aerial devices, Inventors: Jacques de Lesseps • Roger Courtois-Suffit)
• Patent FR-1917-503731 (English title: Landing indicator for aircraft, Inventors: Roger Courtois-Suffit)
• Patent US-1917-1339006 (English title: Aeroplane height indicator, Inventors: Lawrence Burst Sperry, Applicant firm: Lawrence Sperry Aircraft Company, Inc.)
• Patent FR-1916-520777 (English title: Device for automatic stabilization of flying machines, Inventors: François Dergint)
• Patent DE-1919-342269 (English title: Device for determining the lift of aircraft surfaces using a vehicle carrying the surface under investigation, Inventors: Detlev Zickler)
• Patent US-1915-1390653 (English title: Steering Device for Aircraft, Inventors: Lawrence Burst Sperry, Applicant firm: Sperry Gyroscope Company)
• Patent HU-1917-80687 (English title: Apparatus for determining the altitude of a point by means of a headlamp and an optical instrument for the observation of reflected rays, Inventors: Oscar Gerhardt)
• Patent US-1918-1450431 (English title: Landing indicator for aircraft, Inventors: Roger Courtois-Suffit)

Links

• Shaw, 1926, Manual of Meteorology, pp. 226–227 for comparison of instrument types used at different observatories