Decades: 1200s 1210s 1220s 1230s 1240s - 1250s - 1260s 1270s 1280s 1290s 1300s
Years: 1252 1253 1254 1255 1256 - 1257 - 1258 1259 1260 1261 1262
Births
Deaths
... physics of this device looks confusing at first sight, but is surprisingly simple. It can easily be understood with a little knowledge of gyroscopes. The ...