Centuries: 12th century - 13th century - 14th century
Decades: 1190s 1200s 1210s 1220s 1230s - 1240s - 1250s 1260s 1270s 1280s 1290s
Years: 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
... covers the gyroscope inside it, except for a small round opening on top of it, which is where you can manually start the gyroscope. Once the gyro is spinning, ...