WCP2479

[1]

Harlton

Cambridge

16 December 1893

Dear D^r Wallace

I have just read your article on the erosion of lake basins.¹ It is excellent. The argument from the outline of a lake basin compared to that of a submerged valley is to me a new one (as you claimed it to be) and I think a striking one.

In your former paper² there is one point on which I am not convinced. I do not feel sure about all boulder clays being till.³ I have boulder clay within⁴ half a mile of my house. The stones I pick up seem to me better explained by floating ice from a long stretch of [2] cliff than by an ice sheet. I have in former years worked a good deal in Norfolk and Suffolk & am incli[ined] to the iceberg theory for the glacial phenomena of that district. I think no one doubted this till James Geikie⁵ came down [illeg] from the scotch till & turned our heads.

Unfortunately I made a mistake in a numerical value I took out of Thomson & Tait⁶ for my paper on Darwin's theory of the Genesis of the Moon⁸ & afterwards referred to in a paper in the Amer. Journ. Science. I am writing a short apology for the latter & I intend to insert something like the enclosed in it. Will you kindly tell me what you think of the argument.

Becker fell foul of my theory [3] about dissolvent gas in the magma referring to your article in the Fortnightly. He says it is founded on a mistake but does not say what the mistake is. I know however from a private letter from him what he means & I am by no means sure the mistake is not his. If what he asserts is true there could be no such thing as a water barometer.

Believe me | sincerely yours | Osmond Fisher⁸ [signature]

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