Ship's Magnetism

IN a review of my book on the subject of the “Deviations of the Compass in Iron Ships” which appeared in NATURE of June 18 and in the last paragraph, there are statements to which I would take exception. In this paragraph the reviewer finds “food for reflection” in that, after defining C.G.S. units in the introduction of my book, I stick to inches and to other units in the text and charts.