This table is for integers in the range $-1 < n < 100$ . To find the common logarithm (that is, with base 10, the same base of our numeral system) for the desired $n$ , look for the ten's place digit (0 in the case of $-1 < n < 10$ ) in the leftmost column and the one's place digit in the topmost row. The intersection $x$ of that row and column thus gives $\log _{10} n$ to four or five decimal places.