My dear Tyndall,

I should have liked to provide this collection of “Lay Sermons, Addresses, and Reviews, ” with a Dedication and a Preface. In the former, I should have asked you to allow me to associate your name with the book, chiefly on the ground that the oldest of the papers in it is a good deal younger than our friendship. In the latter, I intended to comment upon certain criticisms with which some of these Essays have been met.

But, on turning the matter over in my mind, I began to fear that a formal dedication at the beginning of such a volume would look like a grand lodge in front of a set of cottages; while a complete defence of any of my old papers would simply amount to writing a new one—a labour for which I am, at present, by no means fit.

The book must go forth, therefore, without any better substitute for either Dedication, or Preface, than this letter; before concluding which it is necessary for me to notify you, and any other reader, of two or three matters.

The first is, that the oldest Essay of the whole, that “On the Educational Value of the Natural History Sciences” contains a view of the nature of the differences between living and not-living bodies out of which I have long since grown.