Decades: 1120s 1130s 1140s 1150s 1160s - 1170s - 1180s 1190s 1200s 1210s 1220s
Years: 1174 1175 1176 1177 1178 - 1179 - 1180 1181 1182 1183 1184
Births
Deaths
... the device will cause the gyroscope to start precessing, with its axis slipping around in the groove in a circular fashion. The groove inside the device, is a little ...