Take any printed book and open its pages at random, and select a word within the first ten lines, and within the tenth word from the end of the line. Mark the word. Now double the number of the page, and multiply the sum by 5.

Then add 20.

Then add the number of the line you have selected.

Then add 5.

Multiply the sum by 10.

Add the number of the word in the line. From this sum subtract 250, and the remainder will indicate in the unit column the number of the word; in the ten column the number of the line, and the remaining figures the number of the page.