THE TIME TAKEN UP BY CEREBRAL OPERATIONS. 381 XV.) ten colours, the observer not knowing which was to come, but not needing to distinguish it before making the motion. TABLE XIV. B < ~i R V R' V R V R' V 6. I 250 20 253 15 236 21 233 16 14 227 19 226 7 236 13 234 10 19 245 21 249 13 231 14 230 8 20 215 20 212 14 244 12 243 7 31 227 10 227 7 246 21 241 13 A 233 18 233 11 239 16 236 11 TABLE XV. ] B c ] B 1 ^ R R' R R' R R' R R' Orange Violet Black 22. XII 291 262 950 296 269 953 258 251 936 261 255 933 22. XII 289 260 963 293 254 955 245 259 250 237 263 253 Pink 6.1... 968 963 970 966 6. I... 938 949 245 240 Brown 7 995 990 967 963 7 978 98'? 241 244 Gray 9 991 980 967 965 9 934 937 276 277 Red Blue 10 277 965 282 963 264 984 265 979 2. II 230 919 230 993 232 242 229 237 Green 969 964 968 968 999 919 245 244 Yellow 264 262 280 286 230 228 254 257 A 979 979 964 964 947 946 949 248 AV 90 13 18 13 95 17 94 17 False 1
9
It thus takes a little longer to recognise the presence of a colour
(even though the colour need not be distinguished) than of a white
light. It is to be noticed that B's times became shorter in 1885
than they were in 1884.
We next determine the perception-time when it is necessary to
distinguish the colour. Two cases were considered ; in one the
colours were taken in pairs, and one colour was distinguished
