VI

PREFACE.

the octavo volume (without photographs) to accom-pany his large volume of photographs (see p. 400), heprovides the smaller photographs for the completeoctavo treatise, on pre-arranged terms.

I take this opportunity of thanking Mr. Eutherfurd,on Mr. Brothers’s behalf and my own, for his liberalityin permitting the publication of his admirable photo-graphs. I feel that the prospects of this work’ssuccess have been greatly enhanced, also, by theskill with which Mr. Brothers has enlarged thesebeautiful pictures of our satellite. (See advertisementleaf, p. 400.)

While this treatise has been in progress, I have heardthat a work on the Moon has been commenced underthe supervision of a well-known student of the Moon ;and my friend Mr. Webb has mentioned his ownintention of writing one day a book upon the samesubject. It seemed to me, therefore, desirable, whilepresenting so much as was necessary for the complete-ness of the present work on the parts of the subjectwhich the promised works are severally likely to treatwith special fulness, to devote my chief attention tothose departments to which my own tastes chieflyinvited me. It is perhaps hardly necessary to remarkthat in any case some portions of the subject musthave been less fully treated of than others, and someomitted altogether, since, in fact, ten such volumesas the present would be insufficient to deal satisfac-torily with all the matters of interest connected withthe Moon .