Henry Briggs

“ The number of quotients in the latter case will be 100, (for the product ts its hundredth power; and if a number be multiplied by itself a given number of times forming a certain product, then it will divide the product as many times and once more; for example, of 3 be multiplied by itself four times it makes 243, and the same 3 divides 243 five times, the quotients being 81, 27, 9, 3, 1.) In the former case, where the product is continually divided by 10, it is manifest that the number of quotients falls short of the number of places in the dividend by one only. ”

“ If 3 multiply itself six times, you will have 2187 for the power which, in a series of continued proportionals from unity, will occupy the seventh place, and hence it may, without inconvenience, be called the seventh power. The same number, 2187, is the fourth power from unity in another series of continued proportionals, in which the first power, , is the required second sine. The product of the quotients 4 and 7 is 28, which, multiplied by the common divisor 2, makes 56, the Logarithm of the power 2187. ”