The first three editions of this book, written in Spanish, appeared at a time (1945, 1949, 1951) when the full impact of the classical investigations of Wilson and his school began to be felt not only within but beyond the borders of the United States. The rather sudden awareness, especially in the southern part of the Western Hemisphere, of the quantitative approach to electrocardiography was the result not only of Wilson's extensive lecture tour in 1942 of the Latin American countries, but also of the generous acceptance into his laboratory and tireless teaching of almost every important electrocardiographer living below the Rio Grande today. One of the most capable and productive of these has been Sodi-Pallares.
The first English translation, ably accomplished with the help of Royall M. Calder, is a revised version of the third Spanish language edition. Like the latter, it consists of eleven