One of our early school activities would have been printing patterns and shapes on to paper by using a sponge or potato with a design that we cut into the flat surface. Transferring the pattern onto paper is called printing or 'offsetting'. The ink that is used in ball pens is very thick. Even thicker than treacle or syrup, and is made from oils and dyes.
Ballpoints write for a very long time.
If all the writing from one Parker ball pen refill was made as a straight line, it would be more than five kilometres long. In making that line, the little ball in the point could have rolled round more than 3 million times. Gravity makes the ink in the pen fall onto the ball as it sits in its socket. As the pen is moved across the paper the ball turns, and the ink is transferred onto the paper. The ball at the tip is sometimes only half a millimetre in diameter.