USA ( 1970 / 1980 )
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
Body Sizes ( W7 / W8 * D * H ) = 2_1/2 / 3" * 5_1/2" * 5/16"
(= 65 / 75 mm * 140 mm * 8 mm )
Have a Look at the HISTORY
impressum:
*******************************************************************
© C.HAMANN http://public.BHT-Berlin.de/hamann 09/08/08