Robinson Crusoe by Daniel Defoe Chapter 4 Page 43

or twelve days, it came into my thoughts that I should lose my reckoning of time for want of books, and pen and ink, and should even forget the Sabbath days; but to prevent this, I cut with my knife upon a large post, in capital letters - and making it into a great cross, I set it up on the shore where I first landed - “I came on shore here on the 30th September 1659.”

Upon the sides of this square post I cut every day a notch with my knife, and every seventh notch was as long again as the rest, and every first day of the month as long again as that long one; and thus I kept my calendar, or weekly, monthly, and yearly reckoning of time.

In the next place, we are to observe that among the many things which I brought out of the ship, in the several voyages which, as above