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History of Computers: Perhaps the most advancement evolution in mechanical calculators was the introduction, in 1642, of the ´toothed wheels´ (gears) by Blaise Pascal (1623-1662), the famous French philosopher and mathematician. Pascal's father, Étienne Pascal, had unorthodox educational views and decided to teach his son himself. He decided that Pascal was not to study mathematics before the age of 15 and all mathematics texts were removed from their house. Pascal however, his curiosity raised by this, started to work on geometry himself at the age of 12. He discovered that the sum of the angles of a triangle are 2 right angles and, when his father found out, he gave Pascal a copy of Euclid. At the age of 14 Pascal started to attend Mersenne's meetings. Mersenne belonged to the religious order of the Minims, and his cell in Paris was a frequent meeting place for Fermat, Pascal, Gassendi, and others. At the age of 19 Pascal invented the first digital calculator (1642) to help his father. Although limited to addition and subtraction, the toothed counting wheel is still used in adding machines and it may be of interest to look for a moment at its simple operating principle. Several wheels with teeth numbered from 0 to 9 are arranged in a row representing ones, tens, hundreds, thousands, etc. The Number that is to be operated upon is represented by the tooth that faces the index above each wheel (a viewing window in an actual machine). For example, the number 456 is represented by the position of the toothed wheels. If you wanted to add 111 to this number, you would simply turn each wheel by one tooth, so that the teeth indicating 5,6, and 7 would face the index or viewing windows. The result of the addition of 456 and 111 appears at the viewing window. |
