Utopia by Thomas More Chapter 1 Page 10

found ships made with round keels and canvas sails, and in all respects like our ships, and the seamen understood both astronomy and navigation. He got wonderfully into their favour by showing them the use of the needle, of which till then they were utterly ignorant. They sailed before with great caution, and only in summer time; but now they count all seasons alike, trusting wholly to the loadstone, in which they are, perhaps, more secure than safe; so that there is reason to fear that this discovery, which was thought would prove so much to their advantage, may, by their imprudence, become an occasion of much mischief to them.

But it were too long to dwell on all that he told us he had observed in every place, it would be too great a digression from our present purpose: whatever is necessary to be told concerning those