Genaille` bars

Calculating bars for division

1885

The engineer Henri Genaille became aware of the problem of the decimal transfer of the Napier bars in 1885 through the mathematician Edouard Lucas. He subsequently developed new staffs for multiplication and division. The shown bars can be used for dividing. To do this, you place the bars next to each other in such a way that the uppermost numbers give the dividends. To the right of it the index stick is created. You start by searching for the divisor in the right column of the index bar. In the following, one remains in the horizontal segment in which the divisor is located. You go to the top number of the left stick in this segment, follow the line from left to right across the sticks and you get to a number on the index stick. The numbers on the lines form the result. E.g. 98281 divided by 4: You start with 2 and follow the lines: 4, 5, 7, 0, 1 and get the result 24570, rest 1.