Presented is a rarely seen C. Plath Bubble Horizon in absolutely outstanding and flawless condition. There is no instruction booklet, but the device is simple to use and provides an artificial horizon using paired cross-hairs giving a horizontal and vertical reference. Thebubble is centered at the midpoint of the cross-hairs and the celestial body is brought into coincidence with the bubble’s center. The serial number shows the design as 1978 manufacturer and the Deutsch Hydrographic Institute indicia shows that it is certified for use in commercial service. Cassens & Plath, no relation to C. Plath, offers a more simplified version
of a bubble horzion which is priced at $1000.00.
The bubble horizon is attached to the sextant in the normal way, and its power
cord with male prong fits either of the two female receptacles that are found on both the C. Plath and Cassens
& Plath sextant handles. The electric power illuminates the cross-hair and bubble images and reflects the images into the bubble chamber. The intensity of the light is adjusted by the knurled knob at the top. The system will fit a wide variety of other sextants including Tamaya and the Russian CHOT, but an auxiliary power source will have to be provided.
CONDITION: This instrument shows no discernible
evidence of wear that it can be considered as new.
MARKINGS:
On the side:
CPLATH, No. 2797, W. Germany.
On the end cap: DHI, 10/2/1/78
THE SEXTANT PICTURED IS NOT INCLUDED
SUGGESTED USE: The bubble horizon has a
2 power optical system and a smaller than normal field of view. The internal dampening mechanism of the bubble is greater than will be found on less costly alternatives, but requires some practice in getting used to. The knurled knob of the upper cylinder adjust the intensity of the light. The Plath Bubble Horizon is far superior to a normal artificial horizon which can only be used for objects with altitudes of less than 60 degrees and can not be used for twilight sights. This makes it ideally suited for land based training applications, for land navigation and for use at sea from ships large enough to be a stable platform. Interestingly, in the 1970-80’s this device, in an earlier form, was issued to U.S. submarines for back-up celestial navigation. Ref. Dutton’s Seamanship & Navigation, 12th Edition, Article 2206, page 385.
- PLATH BUBBLE HORIZON SPECIFICATIONS:
Magnification 2 X estimated
4″ H x 4 1/4″ L x 1 3/4″ W
Slip-on green filter included
Weight: 7 oz
This
device is suited for someone who can appreciate the fine points of its design, and is willing to pay an appropriate price for this level of C. Plath quality and excellence.
COMPANY HISTORY: In brief, Carl Plath started manufacturing sextants, in addition to other nautical products, in Hamburg Germany in 1862 though the company’s origin dates back to 1837.
As a result of WW II, C.Plath was dismantled completely by the occupation forces. Around 1950, various prohibitions
were lifted, and C. Plath was allowed to begin production again of sextants and other nautical instruments. Also in 1949,C.Plath was offered a gyrocompass patent and in 1951 the first gyrocompass designed to this patent was presented to the public. C.Plath progressed from the role of instrument maker to that of a modern marine navigation equipment manufacturer. In the following years the product range was expanded by many more modern designs such as autopilots, speed logs, radio direction finders, etc.
In 1962 C.Plath was acquired by Litton Industries, a large American concern.The C.Plath North American Division was set up in 1978 in College Park near Washington. 1996 saw the introduction of the world’s first fiber-optic solid-state gyrocompass by C.Plath. The first ever gyrocompass with no moving parts. Sperry Marine was formed in 1997 with the combination of C.Plath, Decca Marine and Sperry Marine with more organizational changes yet to come. After 163 years, C.Plath changes its name to Sperry Marine in May 2000. In 2001 Sperry Marine becomes part of the Northrop Grumman Corporation, and shortly thereafter discontinues sextant production. All parts, machinery, and tooling were destroyed.
