Centuries: 4th century - 5th century - 6th century
Decades: 390s - 400s - 410s - 420s - 430s - 440s - 450s - 460s - 470s - 480s - 490s
Years: 440 441 442 443 444 445 446 447 448 449 450
... takes a while until one finds the "rolling" point, but the gyro will also be accelerated to a smaller extent by the slipping friction. The device is covered by ...