A shepherd upon one of the mountains in Cumberland, was suddenly enveloped with a thick fog or mist, through which every object appeared so greatly increased in magnitude, that he no longer knew where he was. In this state of confusion he wandered in search of some unknown object, from which he might direct his future From these effects of vision, it is evident that the pupil and the picture of an object within the eye, increase at the same time. The writer of the above account was passing the Frith of Forth, at Queensferry, near Edinburgh, one morning when it was extremely foggy. Though the water is only two miles broad, the boat did not get within sight of the southern shore till it approached very near it. He then saw, to his great surprise, a large perpendicular rock, where he knew the shore was low and almost flat. As the boat advanced a little nearer, the rock seemed to split perpendicularly into portions, which separated at a little distance from one another. He next saw these perpendicular divisions move; and, upon approaching a little nearer, The following extract of a letter, from a gentleman of undoubted veracity, is another curious instance of the property of vision:— "When I was a young man, I was, like others, fond of sporting, and seldom liked to miss a day, if I could any way go out. From my own house I set out on foot, and pursued my diversion on a foggy day; and, after I had been out some time, the fog or mist increased to so great a degree, that, however familiar the hedges, trees, &c. were to me, I lost myself, insomuch that I did not know whether I was going to or from home. In a field where I then was, I suddenly discovered what I imagined was a well known hedge-row, interspersed with pollard trees, &c. under which I purposed to proceed homewards; but, to my great surprise, upon approaching this appearance, I discovered a row of the plants known by the name of rag, and by the vulgar, canker weed, growing on a mere balk, dividing ploughed fields: the whole height of both could not exceed three feet, or three feet and a half. It struck me so forcibly that I shall never forget it; this too in a field which I knew as well as any man, could know a field." |