REVIEWS. 
55 
referred to. Of the new species a considerable number are Rays. Fourteen 
new genera are established, and among these forms of Pleuronectidae 
seem to be most numerous. The plates, thirty-two in number, illustrating 
this report, are most admirably executed, and display the beautiful or 
grotesque characters of the fishes very clearly. 
We have felt it a duty to enter in some detail upon the consideration 
of this volume as being not only in itself a repository of most valuable 
materials, but also, we may hope, the precursor of others, at least not less 
rich in interest and information. The zoological Reports of the Challenger 
expedition, if carried out throughout in the same spirit, will certainly bear 
comparison with any work of the kind. We may add that the volume is 
issued at a very moderate price, and that the different memoirs may be 
purchased separately. Also that the sale has been entrusted to several 
publishers in London and elsewhere. 
ELEMENTS OF ASTRONOMY.* 
T HIS is one of the new volumes of Longman’s Text Books of Science 
adapted for the use of students, and is a work therefore which 
should give a full and explicit treatment of its subject, so as to enable 
its readers to obtain a sound knowledge of the elements of the branch of 
Science to expounding which it is devoted. Above all, the information it 
contains should be trustworthy, and carried up to recent date. It cannot 
be said that this volume fulfils these ends. It is a very unsatisfactory 
work, as nearly every section shows evidence of inexperience and want 
of familiarity with its subject ; all the more surprising as the work is 
from the pen of the Royal Astronomer for Ireland, and the head of the 
principal Observatory therein, that of Dunsink. 
The work is divided into twelve chapters and some 273 sections, each 
section treating of its subject in the semi-isolated form so customary 
in mathematical text-books in common use at the Universities. These 
sections are badly arranged, those devoted to analogous subjects being 
often widely separated ; and they are commonly devoted to the lengthy 
exposition of subjects which seem to indicate a strange inexperience of the 
requirements of astronomers. At times several pages are given up to the 
elaborate treatment of unimportant matters, whilst subjects of far more 
importance are dismissed in a few lines. Again, a subject is introduced 
and partially discussed, only to be taken up again and re-discussed at 
another time. Further, at times essential points are baldly stated and 
required to be taken on trust, whilst the minor points connected with them 
are made the subject of elaborate geometrical discussion. All these are 
grave faults in a work designed for students. 
In many instances remarkable inexperience is shown in the quotation of 
authorities and data, as if the author was unaware of their merits ; in many 
cases old and untrustworthy results are quoted, and more modem and 
* Elements of Astronomy. By Robert Slawell Ball, LL.D., F.R.S. 
Andrews Professor of Astronomy in the University of Dublin, Royal 
Astronomer for Ireland. 8vo. London, Longmans, 1880. 
