Averroes 151
Ayangkidarrba (Groote Eylandt) 227–30, 228, 233
Aztecs 278
Babylon 83, 85, 86, 87
Bacon, Francis 174, 179
Baghdad 142, 148, 149, 155, 170
ballot tokens, Athenian 101–5, 103
bar-and-dot numerals 277, 278
bark 145, 150, 228, 236, 261, 264, 272
barometer 177, 179
base numbers
Arabic numerals and 184
Australian languages and 233, 234
base-5 60, 230
base-10 60–1, 184, 233
base-60 81, 83, 86, 95
defined 60
finger counting and 60–1
hieroglyphic script and 95
hunter-gatherer groups of the African Stone Age and 60–1
Mayan 273
number symbols and 182–3, 184, 230
Sumerian 73, 81, 83, 86
Yup’ik and 261
beads 4, 7, 61, 62, 64, 73, 82, 181, 253, 276, 285, 287, 289
Blombos Cave and origin of counting with 31, 32–7, 33, 39, 48, 58
Pomo bead money 262–9
shell beads 32, 34–5, 39, 48, 58, 232, 264, 266, 287, 288
suanpan/soroban and 196–203, 198
Bear River people 266
Bede, Venerable: The Reckoning of Time 113, 116–17
bees 28
Bering Strait 253, 256
Bhaskara II 136–7, 142–7, 151, 156, 163, 170, 181; Lilavati 143–7, 144, 145
binary 135, 185, 186, 219, 220, 221
birds 11, 15, 19, 20, 20, 24, 25, 28
Blanche of Castile 121–5, 123, 125, 129, 131, 132
Blombos Cave, South Africa 32, 33, 34–7, 39, 58
board arithmetic 150
boards, counting 6, 82, 99–100, 118–33, 158, 184, 196–7, 288
