Accession No
6372
Brief Description
Gerber Variable Scale in a brown, leather bound case with a black Allen key; The Gerber Scientific Instrument Company, Hartford, Connecticut, U.S.A.; c. 1948 - 1976.
Origin
Hartford, Connecticut, U.S.A.
Maker
The Gerber Scientific Instrument Co.
Class
drawing; cartography; earth sciences
Earliest Date
1948
Latest Date
1976
Inscription Date
Material
Metal; plastic; paint; hide (leather); fabric (thread, other); paper (cardboard, other); cloth (felt)
Dimensions
Case: height 27 mm; width 594 mm; depth 60 mm.
Special Collection
Tjeerd Van Andel collection
Provenance
Donated by an individual from the Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, 16/07/2009.
Inscription
‘THE GERBER SCIENTIFIC INSTRUMENT COMPANY HARTFORD. CONN. GERBER VARIABLE SCALE MODEL TP007200B PATS. 2530955 . 2561020 PTHERS PEND. MADE IN U.S.A.’
(engraving on front of instrument)
20500 (scratched onto right-hand end of ruler)
‘THE GERBER SCIENTIFIC INSTRUMENT CO.
HARTFORD, CONNECTICUT’
(printed on inside of case)
‘Tj. H. van Andel
School of Oceanography
Oregon State University
Corvallis, OR 97331’
(printed on sticker on front of case)
‘VAN ANDEL’
(written on front of case with marker pen)
Description Notes
Gerber Variable Scale in a brown, leather bound case with a black Allen key; The Gerber Scientific Instrument Company, Hartford, Connecticut, U.S.A.; c. 1948 - 1976.
The main body of the scale is a black rule composed of a silver metal beam and a black plastic top; The plastic top has four scales stamped onto it; The four scales are divided into two couple, one of which is marked ‘RI’ and the other ‘RF’; There is a silver metal slide which moves up and down the black rule and is connected to a metal spring with triangular coils; The side of the coils that face out are painted white, with every fifth coil alternating red and green; The triangular spring is connected to a standard coil spring that runs parallel; Attached to this spring are numbers that mark this ruler’s major division in multiples of two; Two two springs are protected by a clear plastic cover; The ends of the scale are secured with silver metal bolts; Along the bottom side of the black rule is the inscription: ‘THE GERBER SCIENTIFIC INSTRUMENT COMPANY HARTFORD. CONN. GERBER VARIABLE SCALE MODEL TP007200B PATS. 2530955 . 2561020 PTHERS PEND. MADE IN U.S.A.’; Scratched onto right-hand end of ruler is the inscription ‘20500’
The instrument is in a brown, leather-bound case composed of cardboard and stitched together with thread); The case is secured with two snap fasteners; ‘VAN ANDEL’ has been written on the top side of the case in black ink and there is a sticker with the following printed onto it: ‘Tj. H. van Andel
School of Oceanography
Oregon State University
Corvallis, OR 97331’
The inside is fitted with a black felt lining; The following inscription is printed onto the felt inside case:
‘‘THE GERBER SCIENTIFIC INSTRUMENT CO.
HARTFORD, CONNECTICUT’
Inside the case there is also a handmade paper envelop which contains a black Allen key.
Condition: Fair; incomplete, missing one number from spring and *might* be missing an instruction manual (the Gerber Variable Scale shown on the following website is reported to have been missing it’s instruction manual: http://www.nzeldes.com/HOC/Gerber.htm); Case is worn; Instrument is missing the numbers ‘10’ and ‘14’ that ought to be attached to the metal coil spring.
References
Events
Description
The Gerber variable scale can be used to solve problems involving proportions, interpolations, and scaling of data plotted on paper. For instance, measuring a distance on a map is one of it’s more basic operations. With a rule, this operation requires measuring a distance on the map in centimeters or inches and multiplying this measurement by the map’s scaling factor to find the distance in kilometers or miles. However, Gerber’s scale can be used to eliminate the multiplication calculation - the triangular coils can be stretched to (say) a distance equivalent to a kilometer on the map, allowing measurements of other distances to be made directly. However, more complex calculations and operations may be performed on graphs, oscillograms and drawings, where the spring is used in conjunction with the scales printed on the rule.
This particular Gerber variable scale was owned by Professor Tjeerd Van Andel (Department of Earth Sciences, University of Cambridge), obtained whilst he was at the School of Oceanography at Oregon State university. It may have been used to measure distances on maps or for more complex cartographic calculations.
19/08/2009
Created by: Coxhead, M.A. on 19/08/2009
FM:46885
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