Advanced Examples in Physics by Arthur Ormiston Allen. CONSIDERABLE difficulty has been met with in the Degree courses in Physics at Leeds University in setting numerical examples of a fairly advanced type, and I doubt not that the same difficulty will have been felt elsewhere. No teacher can afford to dispense with so important a test of the progress of his students as the working of calculations based on the subject-matter of the lectures; yet there appears to be no collection of suitable exercises published at a moderate price. The dictation of questions to a class absorbs valuable time, and the handing round of loose leaflets is a troublesome process. Moreover the large number of students working privately for the examinations of London University must find themselves at a great disadvantage if, as often happens, they have not easy access to a set of University Calendars. This book is designed to meet the difficulty referred to; most of the questions are taken from old examination-papers, the source being acknowledged by a letter in brackets at the end of each exercise. The London and Victoria Universities are indicated by the letters L. and V. respectively; H. denotes that the paper was one for Honours candidates. When no letter is added, the question is either original or has been taken from the lecture note-books in use at Leeds; for permission to use the latter I am greatly indebted to Professor Stroud. Questions taken from old papers have as a rule been reproduced in their original form even when improvement seemed possible; the detection of such cases is in itself a useful exercise. A. 0. ALLEN. LEEDS UNIVERSITY.