This meaning I cannot find in Bailey's _Dictionary_, and it has escaped the curious vigilance of Blakie's compilers. The saying, however, is a very old one. Sir Edward Coke employs it (_Coke upon Littleton_, lib. i. c. 1. sect. 1. p. 3. _a._): "But no simile holds in everything; according to the ancient saying, _Nullum simile quatuor pedibus currit_." There is a marginal reference here to 1 Hen. VII. 16. Perhaps some of your philological correspondents can throw some light on the origin of the phrase, or at least give me some other examples of its use. Is the expression "To be on all-fours with" good English? C. MANSFIELD INGLEBY. _Richard, second Son of the Conqueror_, is said by Hume, and by some minor writers after him, to have been killed by a stag in the New Forest; but William of Malmesbury and Roger of Wendover both say that he died of fever, consequent on malaria, which struck him while hunting there. This is well known to be of frequent occurrence in the neighbourhood of desolated human dwellings; and thus seems to involve even a more striking instance of retributive justice than the fate which Hume assigns to him. The fatality attending most of this name in our history is singular. Of nine princes (three of them kings) who have borne the name of Richard, seven, or, if Hume is right, eight, have died violent deaths, including four successive generations of the House of York. J. S. WARDEN. _Francis Walkinghame._--Your correspondent's mention of my _Arithmetical Books_ (Vol. v., p. 392.) reminds me of a Query which I made in it, and which has never obtained the slightest answer--Who was Francis Walkinghame, and when was his work on arithmetic first published? The earliest edition I know of is the twenty-third, in 1787; but I am told, on good authority, that Mr. Douce had the sixteenth edition of 1779. A. DE MORGAN. _Optical Phenomenon._--I shall be much obliged to anybody who will explain a phenomenon which I have observed. Suppose 1. A street from twenty to thirty feet broad. 2. At the open window of a house on one side stands a man looking at the corresponding window of the house on the opposite side; that is, he looks at what was a window, but is now filled up with a large board that is covered with an inscription of short lines, black on white; in short, just such a board as one sees at a turnpike gate. 3. From shortness, or defect, of sight (I cannot say which), the man is unable to read the inscription as he stands at his window. 4. He sits down on a low seat, so as to bring his eye almost close to, and just on a level with, the sill of his own window. He then slowly raises and depresses his head. As he does this, it of course appears to him as if his own window-sill travelled up and down the board opposite. 5. In doing so it comes successively under each line of the inscription. 6. As it does so, that one line becomes perfectly legible. N. B. Minor Queries Answered.