Page:The Sources of Standard English.djvu/458

Rh This work is intended as a companion to any text-book that may be in use, “The main difficulties which boys experience in the different rules are skilfully dealt with and removed” —.

In this volume an attempt has been made to produce a treatise on the Planetary theory, which, being elementary in character, should be so far complete as to contain all that is usually required by students in the ''University of Cambridge. In the New Edition the work has been carefully'' ''revised. The stability of the Planetary System has been more fully treated,'' and an elegant geometrical explanation of the formulœ for the secular variation of the node and inclination has been introduced.

The first part of this work consists of an application of the method of the ''variation of elements to the general problem of rotation. In the second'' part the general rotation formula are applied to the particular case of the earth.

The object of this volume is to develop peculiarities in the Ellipsoid; and, further, to establish analogous properties in the unlimited congeneric series of which this remarkable surface is a constituent.

This series of Mathematical Exercises is collected from those which the author has, from time to time, proposed for solution by his pupils during