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It might surprise you to know that the ball in a ball-point pen actually prints its ink onto the paper as it rolls over the paper 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. |
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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. How many times do you think it rotates when you draw a straight line one metre long?
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Every year the people at Parker make more than 45 million ball point pen refills. If they laid them end to end the line of refills would stretch further than the distance across America from New York to Los Angeles.
If they drew a line using all the ink in each of the refills they make in a year, we would have a continuous line from the Sun, passing Mercury, Venus, Earth and reaching Mars. |
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Sometimes, a few hundred years ago, people wrote letters to their friends like this. They filled the page writing one way, and then turned it round 90 degrees, and wrote again over the top. Why did they write like this? Prior to the introduction of the Penny Postage in 1840, one of the factors affecting the cost of posting a letter was whether it was a single sheet of paper. Two sheets would double the cost. That might not sound like a big problem today, but at that time the cost of sending letters had escalated to such an extent that if you could write twice on the same sheet of paper, you could in effect, send two sheets for the cost of one.
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Back in the middle ages, books were hand copied by monks. They not only wrote the words out with quill pens on vellum (dried animal skins), but they painted tiny pictures on the pages as well. In those days, ordinary people could not read, and books were only owned by very rich people, because they were so expensive to make. |
