Lawrence Engineering Service, Wabash, Indiana, 8-B, closed frame, wood, eight inch slide rule, dating from 1935-8, scales: A{B,C1,C}D,K. Instructions printed on reverse. Complete with crude card box
Lawrence Engineering Service, Peru, Indiana, 10-B, closed frame ten inch slide rule. White painted wood with printed scales and instructions on reverse. Magnifying cursor. Scales: A{B,C1,C}D,K. (No it isn’t bent - just camera distortion!!).
Came with Instruction book dated 1939 seen on the left so the rule dates to between 1939 and 1947 when the firms name changed to Engineering Instruments.
Lawrence slide rules were, I believe, sold by Woolworths in the UK.
Came with Instruction book dated 1939 seen on the left so the rule dates to between 1939 and 1947 when the firms name changed to Engineering Instruments.
Lawrence slide rules were, I believe, sold by Woolworths in the UK.
Pickett & Eckel N-902-ES Simplex Trig ten inch slide rule. Aluminium open frame with plastic cursor with “eye-saver” yellow scales. Scales are K,A{B,T,S,C1,C}D,L with tables on the reverse. Complete with a leather slip case. Date probably 1950s.
Pickett & Eckel N-500-T Hi Log Log ten inch duplex slide rule. Aluminium open frame with plastic cursor and “traditional” white scales. Scales are:
+LL2,-LL2,DF{CF,C1F,L,C1,C}D,+LL3,-LL3//+LL1,-LL1,A{B,T,ST,S,C}D,D1,K.
Complete with leather case and belt loop. Date probably 1950s.
Sterling no 587 five inch, closed frame, plastic slide rule with reversible slide and plastic cursor. The scales are: A{B,C1,C}D,K//{S,L,T}. Promotional for Bayport. Complete with clear/blue vinyl slip case.
Other manufacturers in the USA include Pickett & Eckel, Lawrence, Eugene Dietzgen, Sterling and Acumath. Many Japanese made rules were also sold with American names on. For instance the wide range of Post slide rules were made by Hemmi, as were rules for Hughes-Owen.