abacus
The abacus (plural abaci or abacuses), also called a counting frame, is a calculating tool that was in use in Europe, China and Russia, centuries before the adoption of the written Hindu–Arabic numeral system.[1] The exact origin of the abacus is still unknown. in the philippines most of the hardware and construction material stores are owned by chinese. up to the early 1970's, before the onset of calculators, the chinese in the philippines still uses the abacus as their primary adding device. they were so adept in using it that they can do multiple additions in seconds. i have always been amazed with this skill of calculation. nowadays they are all gone
source: wikipedia
abacus
The abacus (plural abaci or abacuses), also called a counting frame, is a calculating tool that was in use in Europe, China and Russia, centuries before the adoption of the written Hindu–Arabic numeral system.[1] The exact origin of the abacus is still unknown. in the philippines most of the hardware and construction material stores are owned by chinese. up to the early 1970's, before the onset of calculators, the chinese in the philippines still uses the abacus as their primary adding device. they were so adept in using it that they can do multiple additions in seconds. i have always been amazed with this skill of calculation. nowadays they are all gone
source: wikipedia