4.9 Lawrence / Engineering Instruments, USA

Lawrence Engineering Service, later named Engineering Instruments, Inc., began in Chicago (as The Lawrence Slide Rule Company) and quickly moved to central Indiana as its base of operation, first in Wabash, Indiana, in 1935 and later to the town of Peru in 1938. It was known for its cheap rules with sufficient accuracy that were often used by students for introduction to the basic scales and operations. In addition to standard Mannheim-style rules, the company also manufactured specialty rules for use in business, such as for lumber, printing, and engraving applications and many others. A major fire destroyed the entire operation on 5 July 1967 at which time the business was ended.

Lawrence Engineering Service, Wabash, Indiana, 8-B.

Lawrence Engineering Service, Wabash, Indiana, 10-C.

Lawrence Engineering Service, Peru, Indiana, 10-B.

Lawrence Engineering Service, Peru, Indiana, 10-D.

Lawrence Engineering Service, Peru, Indiana, 10-N.

Engineering Instruments, Peru, Indiana, 250-BT.

Engineering Instruments, Peru, Indiana, 250-V.

Total number of Lawrence or Engineering Instruments slide rules in the collection: 9.

Model Year Serial Typ Mat Size Case Note
8-B 1935-1938 L wd 7.50 no Lawrence Engineering Service, Wabash, IND.; overall good shape; clean table on back
10-C 1935-1938 L wd 5.00 yes Lawrence Engravers / Photographers Proportion Calculator; Wabash, IN
10-B
1940 L wd 10.00 yes Lawrence Engineering Service; Peru, IN; plastic magnifier cursor
10-B
1942 L wd 10.00 yes good condition; Peru, IN
10-D
1946 L wd 3.75 yes Lawrence Lumber Calculator; Peru, IN
10-N
1946 L wd 6.50 no Lawrence Printer’s Proportion Rule; Peru, IN
10-B
1950 L wd 10.00 no Peru, IN; no cursor
250-BT
1960 L wd 10.00 yes Rule in good condition; blue case; instructions;original box
250-V
1960 L wd 10.00 no Rule in very good condition