Rule for division.
First. Treat the divisor as follows:
If its last figure is a 0, strike this off, and treat what is left as the divisor.
If its last figure is a 5, multiply the whole by 2, and treat the product as the divisor.
If its last figure is an even number, multiply the whole by 5, and treat the product as a divisor.
Repeat this treatment until these precepts cease to be applicable. Call the result the prepared divisor.
Second. From the prepared divisor cut off the last figure: and, if this be a 9, change it to a 1, or if it be a 1, change it to a 9; otherwise keep it unchanged. Call this figure the extraneous multiplier.
Multiply the extraneous multiplier into the divisor thus truncated, and increase the product by 1, unless the extraneous multiplier be 7, when increase the product by 5. Call the result the current multiplier.
Third. Multiply together the extraneous multiplier and all the multipliers used in the process of obtaining the prepared divisor. Use the product to multiply the dividend, calling the result the prepared dividend.
Fourth. From the prepared dividend cut off the last figure, multiply this by the current multiplier, and add the product to the truncated dividend. Call the sum the modified dividend, and treat this in the same way. Continue this process until a modified dividend is reached which equals the original prepared dividend or some previous modified dividend; so that, were the process continued, the same figures would recur.