Abstract :
P. L. Alder: Mr. Spooner´s paper extends by one step our knowledge of those various kinds of core losses which we have been considering for several years in Institute papers. First, we described the line-frequency losses; then, recently, Mr. Spooner described the surface losses; and now the pulsation losses are being attacked. These last losses, though, are the most complicated and the most difficult to understand of all those that occur at no load, and, consequently, it is worth while to point out some of the things that are not mentioned in Mr. Spooner´s paper; which, nevertheless, are very important in this connection.