Chinese Abacus. The abacus is first known in China from the Northern Song dynasty through the work of Shao Yong (1011-1077). Like many early inventions it is not clear precisely where it originally came from. Some say Central Asia; some Asia Minor and others China.
Snag(noun) a stump or base of a branch that has been lopped off; a short branch, or a sharp or rough branch; a knot; a protuberance. Snag(noun) a tooth projecting beyond the rest; contemptuously, a broken or decayed tooth.
jog (third-person singular simple present jogs, present participle jogging, simple past and past participle jogged) To push slightly; to move or shake with a push or jerk, as to gain the attention of; to jolt. jog one's elbow. c. 1593, John Donne, Satire I, Now leaps he upright, Joggs me, and cryes: Do you see.