Adjacent-numbered pages: BP247 BP248 BP249 BP250 BP251  *  BP253 BP254 BP255 BP256 BP257
anticomputer, traditional
Andreas Gunnarsson
Each unit is to be imagined as a flat rigid rod/hoop/triangle/etc.
https://en.wikipedia.org/wiki/Borromean_rings
Similar to BP252.
Adjacent-numbered pages: BP1128 BP1129 BP1130 BP1131 BP1132  *  BP1134 BP1135 BP1136 BP1137 BP1138
precise
Leo Crabbe