2 Telescopes with Rangefinder, R. & C. Avizard (René and Charles Avizard) Paris, about 1880

2 Longue Vue rangefinders, or Telescopes with Rangefinder, made by René Gabriel and Charles Xavier Avizard, around 1880, to be used by the shooting officers of the French Navy Artillery or "Marine Nationale".
The 2 small telescopes are made entirely of bronze and are each equipped with three extendable elements which, together with the main body which includes the objective lens for a diameter of 35 mm, determine a length of 34 cm fully open and 15 cm closed. The telescope probably has 15/20 magnifications.
Within a specific section, there is a graduated lens which allows you to estimate the height of a subject and/or an object detected at a distance and, subsequently, through a quick calculation to be carried out using parameters engraved on a silver table placed on the main body, their effective distance can be determined and then proceed with the adjustments useful for shooting rifles, mortars or cannons.
On each of the 2 rangefinders, there are 2 distinct tables which each show different parameters. It is probable that they were used for shooting adjustments with different weapons,
Size, functionality and sophistication made these small rangefinders for the exclusive use of Artillery Shooting Officers aboard Marine Nationale ships.
Some of the very few optics which took into account such fundamental functionalities for shooting purposes are to be considered extremely important for the time. In fact, the production of the time was concentrated in the production of sighting scopes only and the shooting, mainly, was carried out on very approximate or even "sight" calculations.
They can be fixed to a wooden support using a screw pin.
Their conditions of conservation and functioning are excellent, with a perfectly clear view.

Brothers René and Charles Avizard, together with their father, owned an optical business at 57 Rue Rambuteau in Paris.

In 1880 René and Charles Avizard decided to collaborate by founding together a general partnership for the production of optical and scientific instruments, called "R.& C. Avizard Paris" with registered office in Rue Rambuteau n°57, with share capital of 125,000 francs.

In 1881, they purchased the competing Chevalier business (Arthur had died in 1874 and the store was run by his young daughters). In 1883 the Avizard brothers also took over another large company of eminent opticians, the "Maison de l'Ingéneur Chevallier" opticien du Roi, located at n°15 Rue de Pont-Neuf.

In 1900 René and Charles Avizard moved the shop to 21 Rue Royale and merged all their activities under the name "Maison de l'Ingénieur Chevallier, Avizard Frères, Successors".

Between 1914 and 1921 the shop moved to n°27 Avenue de l'Opéra.