The Further Adventures of Robinson Crusoe by Daniel Defoe Chapter 4 Page 45

This thought terrified them exceedingly; for they concluded, and that not without good cause indeed, that if this fellow came home safe among his comrades, he would certainly give them an account that there were people in the island, and also how few and weak they were; for this savage, as observed before, had never been told, and it was very happy he had not, how many there were or where they lived; nor had he ever seen or heard the fire of any of their guns, much less had they shown him any of their other retired places; such as the cave in the valley, or the new retreat which the two Englishmen had made, and the like.

The first testimony they had that this fellow had given intelligence of them was, that about two mouths after this six canoes of savages, with about seven, eight, or ten men in a canoe, came rowing along