There is a point, however, where psychological and traditional conditions are in natural conjunction, and I will just refer to this. That matters of legal importance should be preserved by the agency of tradition has already been shown to belong to that part of history for which there are no contemporary records, and its importance in this connection has been proved. Equally important from the psychological side is the fact that law is also preserved by tradition where people are unaccustomed to the use of writing, or by reason of their occupation have little use for writing. To illustrate this, I will quote an excellent note preserved by a writer on Cornish superstitions. "There is an old 'vulgar error'--that no man can swear as a witness in a court of law to any thing he has seen through glass. This is based upon the formerly universal use of blown glass for windows, in which glass the constant recurrence of the greenish, and barely more than semi-transparent bull's eyes, so much distorted the view that it was unsafe for a spectator through glass to pledge his oath to what he saw going on outside. Now, through our present glass, this belief is relegated to the region of forgotten things, but nevertheless it has hold on Westcountry people still. I was, some years since, investigating the case of a derelict ship which had been found off the Scilly Islands, and towed by the pilots into a safe anchorage for the night. Next morning the pilots going out to complete their salvage, saw some men on board the derelict casting off the anchor rope by which they had secured her, but they distinctly declined to swear to the truth of what they had seen, and it turned out that they had seen through glass, by which they meant a telescope. In the same case I found that when these pilots (men intelligent much beyond the average, as all Scillonians are) had, on boarding the derelict (which had, of course, been deserted by her crew), found a living dog, they had deliberately thrown it overboard. They explained this act of cruelty to me by saying that a ship was not derelict if on board of her was found alive 'man, woman, child, dog, or cat.' And it turned out, on after-investigation, that these were the very words used in an obsolete Act of Parliament of one of the early Plantagenet kings, forgotten centuries ago by the English people, but borne in mind as a living fact by the Scillonians."[267]