Sir John Herschel, who possesses in an eminent degree, the peculiar talent of felicitously illustrating every subject that he approaches, in his valuable Treatise on Astronomy, thus refers to the situation of London as a Port:—"It is a fact, not a little interesting to Englishmen, and combined with our insular station in that highway of nations, the Atlantic, not a little explanatory of our commercial eminence, that London occupies nearly the centre of the terrestrial hemisphere."