Other people looked for better reasons.
In the sixteenth century, Olaues Magnus, archbishop of Upsal (who, banished to Rome, wrote a book on the antiquities of his country that met with widespread success except in his native land, Sweden, where it was not translated), discovered that, when these stones form one long, straight row, they cover the bodies of warriors who died while fighting duels; that those arranged in squares are consecrated to heroes that perished in battle; that those disposed in a circle are family graves, while those that form corners or angular figures are the tombs of horsemen or foot-soldiers, and more especially of those fighters whose party had triumphed.

All this is quite clear, but Olaues Magnus has forgotten to tell us how two cousins who killed each other in a duel on horseback could have been buried.

The fact of the duel required that the stones be straight; the relationship required that they be circular; but as the men were horsemen, it seems as if the stones ought to have been arranged squarely, though this rule, it is true, was not formal, as it was applied only to those whose party had triumphed.

O good Olaues Magnus! You must have liked Monte-Pulciano exceeding well! And how many draughts of it did it take for you to acquire all this wonderful knowledge?
According to a certain English doctor named Borlase, who had observed similar stones in Cornouailles, "they buried soldiers there, in the very place where they died." As if, usually, they were carted to the cemetery! And he builds his hypothesis on the following comparison: their graves are on a straight line, like the front of an army on plains that were the scene of some great action.
Then they tried to bring in the Greeks, the Egyptians, and the Cochin Chinese! There is a Karnac in Egypt, they said, and one on the coast of Brittany.

Now, it is probable that this Karnac descends from the Egyptian one; it is quite certain! In Egypt they are sphinxes; here they are rocks; but in both instances they are of stone.