Binoculars Carl Zeiss Jena Jagdglas Vergr.=7 1/2

Magnification: 7 1/2x
Aperture (objective diameter): 24 mm
Field of view: 5°
Visible field of view (eyepiece FOV): 37.5°
The closest focusing distance: 3.7 m
Width: 16.6 cm
Height: 14.5 cm
Weight: 775 g
Production date: 1897/98.

   Along with the “civilian” 4x, 6x and 8x Feldstecher binocular models, 4 new “civil” devices were manufactured at the end of 1896: Jagdglas (optics for hunting) Vergr.= 5, Jagdglas Vergr.= 7 1/2, Feldstecher Vergr.= 10 and Feldstecher Vergr. = 12. All of them had objective diameter equal to 24 mm (this value equaled to 25 mm for the binoculars of first releases), the 25 mm eyepiece tube diameter and the 55 mm top prism cover width. The latter had curved design, the so-called “bent shoulders”, which was borrowed from D.F.95 military binoculars, manufactured in 1895. These 4 models were produced in such appearance until 1907/1908 (with an exception of the eyepieces design changes, the upper hinge disc and transition from italics to block letters). Nearly 12,000 of such binoculars were produced between 1896 and 1908.
    The brass-made prism covers of the so-called “bent shoulders” type (binoculars with aluminum covers are not known) and a central hinge, which is attached to binoculars halves with the help of screws belong to distinctive features of Jagdglas Vergr.= 7 1/2x model.
   The civilian application of this model is also proved by the central hinge fixture’s (clamp’s) small diameter (see photo), which has a hole for a knob (included to binoculars delivery kit), with the help of which the hinge could have been finally fixed depending on the observer’s interpupillary distance. The upper hinge disk is flat, without the interpupillary distances scale (it appeared only in 1898). This model’s objective diameter is equal to 24 mm (the earlier model had an aperture equal to 25 mm) and 7 1/2х magnification.
   The binocular possesses eyepieces of the so-called "3/3" design (see Hans T.Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, pp.96-97). The binoculars with such eyepieces design were produced approximately from the end of 1897 to 1899. The eyepieces have a diopter scale (see photo).
   The binoculars frame hinge is attached to its halves with the help of 5 screws from each side. The device has long “lugs” for a neck strap, which are attached to binoculars with the help of 2 screws. There are inscriptions “Carl Zeiss, Jena. D.R.P.” on the left prism cover. D.R.P. is an abbreviation for Deutsches Reichs Patent. There is also an inscription “Jagdglas Vergr.=7 1/2.” – “Binoculars. Magnification=7 1/2” on the right prism cover. The inscription is encrusted in italics (since 1904 the inscription had been made in block letters against the background of Carl Zeiss Tessar photo lens schematic image).
   The binocular’s serial number is "1229" and it was produced in 1897/98. The continuous serial numbering of all Carl Zeiss Jena binoculars was absent at that time (it appeared only at the end of 1907); however there are some facts proving that the serial numbering was of the general type (continuous) within these 4 models with curved upper prism covers - the so-called “bent shoulders” (see Hans T.Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, p.141 and Production of Carl Zeiss Binoculars 1894-1908 by Thomas Antoniades).
   The "younger" model Jagdglas Vergr.=5 is available by the following link http://binocollection.com/catalog/binoculars-carl-zeiss-jena-jagdglas-vergr5.html