Consulting "The Japanese Abacus; Its Use and Theory" by Takashi Kojima (12th printing, 1960) He uses "abacuses" as the plural form. (very interesting history that dates way back to Roman days and farther). Unfortunately I have a somewhat incompatible model from my book, on my wall is a chinese abacus with 5 and 2 beads per digit, where the japanese models use 4 and 1 (which sounds more logical to me, easier to execute a carry to the next digit.) An interesting chapter in the book covers a contest hosted by Stars & Stripes between a U.S. Pvt. in Macarthur's Finance Disbursing Section, (an awarded expert operator of calculators of the tim)e and a Japanese champion abacus operator from the Postal Ministry. As of 1946 the Japanese Abacuses were still able to beat the latest in American calculators. Larry Anderson -- -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- Visit our web page at: http://www.goldrush.com/~foxnhare/ Call our BBS (Silicon Realms BBS 300-2400 baud) at: (209) 754-1363 -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-