Binoculars Carl Zeiss Jena Feldstecher Vergr.=8

Magnification: 8x
Aperture (objective diameter): 20 mm
Field of view: 4.6°
Visible field of view (eyepiece FOV): 37°
The closest focusing distance: 7 m
Width: 14.1 cm
Height: 10.7 cm
Weight: 428 g
Production date: 1898-1899

   This is the most massive civic binocular among first three Carl Zeiss Jena prismatic models having 4-x, 6-x and 8-x magnification.
IMG_0620
   60,000 of such devices were released from 1894 to 1908. Flat prism covers made of brass (the earlier models were made of aluminum) and a central hinge, which is attached to binoculars halves with the help of screws belong to distinctive features of this 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 “earlier” models, 4-x and 6-x have the same fixture design. The upper hinge disk is flat, without inscriptions (the binoculars’ magnification was indicated on it in earlier models and the interpupillary distances scale was indicated on it in later models). This model’s objective diameter is equal to 20 mm (the earlier model had an aperture equal to 18 mm) and 8x magnification. 
   This binocular possesses eyepieces of the so-called "3/3" design (see Hans T.Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, pp.113-114) with the base diameter equal to 18 mm and the top prism cover width equal to 40 mm. The eyepieces’ rotation ability is approximately equal to three-quarters of a turn (270°). The binoculars with such eyepieces design were approximately produced from the end of 1896 to 1899. Such structure is characterized by smooth "monolithic" design with a diopter scale (earlier models did not possess such scale). 
   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 jugular strap, which are attached to binoculars with the help of 2 screws (the earlier models had shorter “lugs”). There are inscriptions “Carl Zeiss, Jenna. D.R.P.” on the left prism cover. D.R.P. is an abbreviation for Deutsches Reichs Patent. There is also an inscription “Feldstecher. Vergr.=8.” – “Binoculars. Magnification=8” on the right prism cover. The inscription is encrusted with the help of silver alloy.
A leather “tongue” for binoculars mounting on a button is not typical for civilian models; it is most likely that someone of its owners installed it on this device himself.
   The continuous serial numbering of Carl Zeiss Jena binoculars was absent at that time (it appeared only at the end of 1907); the new serial numbers were assigned according to the new model release or according to the device design changes. Therefore, relying upon the serial number "5358" and upon the binoculars design (eyepieces joint, the upper hinge disc etc.) one can assume that the binocular was produced approximately in 1898 - 1899. 
   This binocular has a very interesting coffer. It has many peculiarities specific to later series (see Hans T.Seeger. Zeiss Handfernlaser 1919-1946, Modelle-Merkmale-Mythos, pp. 607-627), for example, the seamless bottom design (Nahtloser Kocher), which appeared around 1905, the self-locking (Rolldorn-Befestigung) design of side coffer’s belt fasteners (it appeared in civilian binoculars only in 1907). At the same time, there are some unique features, the information about which is not available in existing sources, for example, the “CARL ZEISS JENA” stamping on coffer’s upper cover, the metal button at the end of a “tongue”, and presence of two belt fastening systems on coffer’s back side. There is high probability that this binocular’s coffer has later origin.