WCP6892

[1]

Waldron Edge, Duppas Hill, Croydon

July 17th 1879

Dear sir

After much consideration of the questions of possible shifting of pole, ^{outer shell} &c. &c. I came to the conclusion that all such changes were too uncertain to found any argument upon, & were, further, inadequate to account for the phenomena observed. I therefore fell back upon the undisputed facts of eccentricity and ^{changes of} position of perihelion, and endeavoured to work out their logical effects on climate. A close study of Croll's writings have led me to adopt most of his views; but I reject some, and I think I have [2] been able to put some points in a clearer light & to show where he has fallen into error. I have summarized my views in a general popular article in the current issue of the "Quarterly Review".

I should be glad to know what you think of it. The first point is a mere summary of well known facts, but from p. 234 onward there are introduced some fresh illustrations & arguments, which I think put the matter clearer than Croll has done, & obviate some of the difficulties of his extreme views as to glaciation

If I have fallen into any errors, geological or astronomical, I shall be obliged by your pointing them out <as the> [3] substance of the article is introduced into a work I now have in hand.

Believe me dear sir | Yours very faithfully | Alfred R. Wallace [signature]

Rev. O. Fisher [4]¹

a(1-e)	= 97 500 000
a (1-a)	= 87 500 000
a2 : [illeg.]	= 10 000 000
a2 : ae	= 5000000
a2 : [illeg.]

I suppose the temp [several lines of illeg. equations]

875 — e	= ? 98321
[illeg.]	1.9431

∴ H/H^' = ((1-e)/(1-e^|))² = 1/48 h

/ 4[?] — e₁ = 1.9926463

[illeg.] = 1.974 [remainder of number illeg,]

more than	.0180886
	.0361772	= [illeg.].10865