ADDITION and SUBTRACTION are operated in the SAME SLOTS

ADDITION  (w. BLACK Figures  on clear background):
--------------------------------------------------
When the figure is in the RED region PULL DOWNWARD
When the figure is in the WHITE region PUSH UPWARD
                with 10s-Carry in the UPPER REGION

SUBTRACTION (w. WHITE Figures on black background):
---------------------------------------------------
When the figure is in the WHITE region PUSH UPWARD
When the figure is in the RED region PULL DOWNWARD
                 with 10s-Carry in the DOWN REGION

Calculator Machine Co.-Mfrs.,
Huntingdon Valley, Pennsylvania / USA (1975)

B o d y   S i z e   ( W * D * H )  =   3_1/2" * 5_3/4" * 1/4"
( =  83 mm * 145 mm * 7 mm  )

Have a look at the BLACK VERSION ...

Have a Look at the HISTORY

impressum:
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© C.HAMANN       http://public.BHT-Berlin.de/hamann        08/05/11