Two other correspondents of the "NOTES AND QUERIES" also, C. H. (Vol. iii., p. 508.) and GOMER (_ibid._), assert that _eysell_, if it means any potion at all, must mean vinegar; C. H. referring to a MS. at Cambridge (Dd. i. fol. 7.), date about 1350, in which occurs,-- "Þe iewis herde þis word wet alle And anon _eysel_ þei mengid wiþ galle:" and GOMER relying on the support of the Welsh word _Aesell_, which implies verjuice or vinegar. D. ROCK, too, adduces the 'Festival' in the sermon for St. Michael's day: "And other angellis with h[=i] (St. Michael) shall bring all the Instrum[=e]tis of our lordis passyon; the crosse; the crowne; spere; nayles; hamer; sponge; _eyseel_; gall, &c." There is therefore, it appears, ample testimony to show that _eysell_ was used for _vinegar_; but to prove that it meant _wormwood-wine_, MR. SINGER'S instances seem insufficient. 13. Before we proceed further, let us, supposing that no bitter or sour potion, but a river, is meant, advert to the consideration what river may be intended? Theobald observed that there was no river of that name in Denmark, nor any resembling it in name but "_Yssel_, from which the province of Overyssel derives its name in the German Flanders." Steevens, however, is well content to take this _Yssel_ as that which Hamlet had in his thoughts. "But," he adds, "in an old Latin account of Denmark, and the neighbouring provinces, I find the names of several rivers little differing from _Esil_ or _Eisill_ in spelling or pronunciation. Such are the Essa, the Oesil, and some others.... The poet," he further remarks, "might have written the Weisel; a considerable river, which falls into the Baltic Ocean, and could not be unknown to any prince in Denmark." MR. SINGER of 1826 suggests that the _Issel_ is perhaps meant, but that the firth of _Iyze_ is nearest to the scene of action. MR. KNIGHT has little doubt that the Yssell, Issell, or Izel, the most northern branch of the Rhine, and that which is nearest to Denmark, is signified. MR. HICKSON, indeed, who favours MR. SINGER'S wormwood-wine, says (Vol. iii., p. 119.), that the word cannot mean a river, because the definite article is omitted before it. But this is an assertion of very little weight. H. K. S. C. (Vol. iii., p. 68.) very justly observes, that we may as correctly say,--"Woul't drink up Thames?" without the article, as "Woul't drink up Eisell?" without the article. Let MR. HICKSON call to mind Milton's lines on English rivers: "And sullen Mole, that runneth underneath And Severn swift, guilty of maiden's death," ending with-- "And Medway smooth, and royal-tower'd Thame," and ask himself whether the names of rivers are not with perfect propriety used without the article. Pope has-- "And sails far off, among the swans of Thames."