A wrong impression is given by the question: “Why will Mr. Ackroyd not have the 19 rivers?” (Geol. Mag., November, 1901, p. 505). The data collected by Sir John Murray are admirable additions to our natural knowledge, and they are used in my last article (Geol. Mag., October, 1901, p. 448), but I contend that they are not available for use in the expression—

and I cannot accept either the minor or major limits of time arrived at in this way. Perhaps a few more lines are necessary to further amplify my reasons.