WCP3976

[1]

Old Orchard,

Broadstone,

Wimborne.

June 23^rd. 1910

My dear Meldola

Many thanks for the analysis of the plaster. Evidently that is not in fault. And as the plaster was dry at the back while it was wet inside, the damp does not come from outside but from the atmosphere, together with the condensed breath of the persons who slept in the rather small room.

As to Herbert Spencer¹, his style in his 'systematic' work is such as to repel many readers [2] His terminology was often obscure and his reasoning ^often tremendously elaborate. But when attacking any special problem of biology or physics he was wonderfully luminous. I remember being greatly impressed by his Linnean paper "On Circulation & Formation of Wood in Plants", published as an Appendix to vol. II. of "Principles of Biology". It is the 2^nd. Appendix, p. 530—560. It shows what a lot of experiments he made and how constantly he appeals to it, & how admirably he reasons on it. He imputes circulation and wood formation to three factors — capillary attraction, osmose, and [3] mechanical strains due to avi-currents. — This paper written in 1865, before Darwin had begun his work on motions of plants etc, shows, I think, that if Spencer had been less of a thinker & more of a specialiser, he would have done all Darwin's work with ease, though perhaps less effectively. I have always been interested in sap-motion, a problem not yet settled, yet Spencer, more than 40 years ago seems to me to have thrown more light on it than anyone else.

An other theory which impressed me greatly is that of the origin of Insects, [4] (Biology II. Chap: 4 & 5), which I made the subject of my address to the Ent. Soc. in 18721. I do not know whether this theory now holds it's ground, but the beauty and clearness of the whole discussion and arguments are very attractive. These, and the "First Principles" are what attracted me most; but we must not forget his wonderful review articles not only on Evolution, — but on the "Stellar Universe", in which he first showed astronomers, the logical results of apparent star-distribution, afterwards demonstrated by Proctor², & now universally accepted; as well as his admirable "Study of Sociology" —"Education" — and other Essays — all illuminated by the great principle of Evolution. On the whole, Spencer, I think, still counts as the greatest all-round thinker and most illuminating reasoner of the 19^th Century.

Yours truly | Alfred R Wallace [signature]