slide projector, balopticon BDT
Date: 1940-1950
Inventory Number: 1997-1-0537a
Classification: Lantern Slide Projector
Subject:
Maker: Bausch & Lomb Optical Company (1853-present)
Place of Origin:
Dimensions:
projector: 29.8 × 55.9 × 14 cm (11 3/4 × 22 × 5 1/2 in.)
case: 32.4 x 43.2 x 19.7 cm (12 3/4 x 17 x 7 3/4 in.)
Accessories: slide carrier, electrical cord, lenses (EE 12 in (305mm))
Bibliography:
Catalog D-111: Scientific Instruments
Bausch & Lomb Scientific Instruments (collection of catalogues)
Description:
The projector is supported by a heavy cast iron base. The latter is equipped with a tilting mechanism so the projector could be placed on uneven surfaces. The front support is adjustable along an inclined groove, permitting inclination in the vertical plane. One of the rear supports is adjustable in a vertical slit, permitting tilting parallel to the axis of the instrument.
The projector itself is fixed at three points to reduce vibrations. The lamp house has a ventilation system and hinged top to facilitate the bulb's change. The light source is 500 watts and 115 volts Mazda lamp. It has a slide carrier and the bellows are mounted on metal frames, sliding on two metal ways. The lens is 2 5/16" diameter lens with a focus length of 12 inches. A carrying case is used for storage.
Projection distances range from 10 to 50 feet with an image size up to 10 feet on the longest side. The original price in 1940 was $70.00.
The projector itself is fixed at three points to reduce vibrations. The lamp house has a ventilation system and hinged top to facilitate the bulb's change. The light source is 500 watts and 115 volts Mazda lamp. It has a slide carrier and the bellows are mounted on metal frames, sliding on two metal ways. The lens is 2 5/16" diameter lens with a focus length of 12 inches. A carrying case is used for storage.
Projection distances range from 10 to 50 feet with an image size up to 10 feet on the longest side. The original price in 1940 was $70.00.
Signedon plaque: BAUSCH & LOMB OPTICAL CO.
FunctionAccording to the 1940 trade catalogue: These [models B and BDT] are the most popular of the Balopticons for use in schools, small auditoriums, Sunday Schools, lodges, and the home. They are inexpensive, sturdy in construction, compact, easily portable and highly efficient. A clear, distinct image can be shown on an ordinary screen under practically daylight conditions... Both models are extremely simple to operate, and convenient."
Curatorial RemarksOwing to the design of B&L shield on the side of the projector, we know it is not an early model of the BDT. This one is definitely after 1940, and before 1951.
Primary SourcesBausch & Lomb, Balopticons and Accessories (Rochester, NY: Bausch & Lomb Optical Co., [ca. 1935]), 14-15.
Bausch & Lomb, Scientific Instruments (Rochester, NY: Bausch & Lomb Optical Co., [ca. 1940]), 179-180.
Bausch & Lomb, Scientific Instruments (Rochester, NY: Bausch & Lomb Optical Co., [ca. 1940]), 179-180.
ProvenanceFrom the Anthropology Department of Harvard University.
