THE nineteenth May Lecture of the Institute of Metals was delivered on May 7 by Sir Oliver Lodge, who chose as his title “Some Ideas about Metals”. A large part of the lecture was devoted to the subject of metallic conduction, a theme selected by two of his predecessors, by Sir J. J. Thomson in 1915, and by Prof. H. A. Lorentz in 1925, but by no means exhausted even now. Adopting the ‘electron gas’ hypothesis as to the nature of metallic conduction, Sir Oliver Lodge discussed in a fascinating manner the phenomena of thermo-electricity and the Hall effect, suggesting the lines along which a solution of outstanding difficulties may be pursued. Great significance is attached to the results obtained by Kapitza in intense magnetic fields, and it is conjectured that a flow along magnetic lines of force, indicated by ether theory but too slow to be observed by existing means, might be detected if such intense fields could be extended over a considerable region instead of being concentrated in a very small space. The earlier part of the lecture, however, was of wider scope, and dealt in a reminiscent vein with some of the anomalies of discovery in physics, such as the failure to recognise a new phenomenon through excessive deference to existing views and the happy results sometimes derived from the exercise of boldness in experiment or speculation. A wide range is covered by the lecture, and the student of the history of physics will find an illuminating survey of some aspects of the growth of the Bohr atom, among many thumb-nail sketches of the physical discoveries of the present generation, from the hand of a master of exposition who has himself been in close contact with such discoveries over the most interesting period in the whole history of the science.