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These have been the first teechdee mechanical functions of rotary motion in the form of the potter’s wheel, the bow drill, the pole lathe, and the wheel itself. It is not potential to be sure when these important units had been invented, but their presence in the early city civilizations suggests some continuity with the late Neolithic Period. The potter’s wheel, driven by kicks from the operator, and the wheels of early vehicles both gave continuous rotary movement in one course. The drill and the lathe, then again, have been derived from the bow and had the impact of spinning the drill piece or the workpiece first in one course and then in the different. It is essential for world society that the present gap between North and South be narrowed. This narrowing ought to be seen not solely as an ethical obligation for prosperous nations but also as in their very own long-term curiosity. Many people need a nudge to get them past a psychological roadblock that is standing in the means