REPOET OF THE SECRETARY. 13 



The ineinoir contains an account of the special apparatus and 

 method of using it, and continues with a description of the emission 

 and absorjjtion spectra of oxygen, nitrogen, hydrogen, carbon monox- 

 ide and dioxide and aqueous vapor for wave lengths, reaching in the 

 case of hydrogen to about 0.10 micron. Illustrations of the apparatus 

 and spectra accompany the text, and it is thought the whole will be a 

 valuable contribution to knowledge, though but preliminar}^ to the 

 researches Doctor Schumann alone is continuing in this spectral 

 region. 



The Institution has accepted, for publication in the Contributions 

 to Knowledge, a memoir by Dr. Frederick W. True, entitk^d "The 

 whalebone whales of the western North Atlantic, compared with those 

 occurring in European waters, with some observations on the species 

 of the North Pacific." This memoir will make a volume of al)out 200 

 pages of text, accompanied ])y about 50 full-page plates illustrating 

 the anatomy and habits of the various species described. 



For manj^ years I have had a liope of preparing for publication a work 

 consisting essentially of photographic views of the moon so complete 

 and, it was expected (with the advance of photography), so minute, 

 that the features of our satellite might l)e studied b}' the geologist and 

 the selenographer nearly as well as by the astronomer at the telescope. 

 This hope has been disappointed, for photography, which has made 

 such eminent advances in the reproduction of nebulas and other celes- 

 tial features, has stood comparatively still in lunar work. We indeed 

 have far better views than were obtained by Rutherford, but the ver}- 

 best even of the admirable ones recently procured b}' Professor 

 Ritchey at the Yerkes Ol^servatory have proved so far behind what 

 the eye can directly discern with the telescope that the expectation 

 that such a work could be advantageously published has been, after a 

 great deal of labor and preparation for many years, most reluctantly 

 al)andoned. During the past 3'ear, however, a memoir has been sul)- 

 mitted to the Institution by Prof. N. S. Shaler, of Cambridge, entitled 

 "A Comparison of the Filatures of the Earth and the Moon." It will 

 be published with some of the best illustrations gathered for the for- 

 mer purpose, and about 25 of these illustratioHis of the moon's surface, 

 including many of the photogniphs taken by Professor Ritchey, will 

 form a prominent feature. The work will prol)a]>ly appear in the 

 early part of the ensuing year. 



In 18()4 the Institution published in the series of Contributions to 

 Knowledge a memoir hy Prof. Henry Draper on the Construction of 

 a Silvered Glass Telescope. The book has long been out of print, and 

 as there seemed to be a present demand for a new edition arrange- 

 ments have been made for its reissue, accomj^anied by an article l>y a 

 competent hand bringing the sul)ject to date. 



To the sei'ies of Miscellaneous Collections two short papers were 



