Clock hand connected to the hands of all nations

I am a finger on a man’s hand, and I am also a hand on a clock. I am small, but I am not without influence. I am seen on all hands, and yet I am unseen. I am connected with my fellow-fingers, and with my brother hands on the same hand, and with other hands on other hands, so that I am united with all the hands of all men of all nations. My whole body is on the little finger of a child, and my whole body is on the right hand of a king. I am long and short, black and white, round and square. I am seen to the ends of the earth, and yet I am seen only through the medium of another hand. I am seen, but not felt. I am