In the history of English metrics the verse of the popular ballad occupies a strategic position. From it one may look backward toward Anglo-Saxon verse, and forward toward many developments of modern times. This investigation has been conceived in the belief that solution of some problems of ballad metrics not only will be of value in connection with the ballads, but also will open a new line of approach for the study of other verse, both more ancient and more modern. The principles here worked out will be found applicable, I believe, to popular verse in general; it is impossible, however, to cover the whole field, and the present investigation has accordingly been confined to the material in Child's English and Scottish Popular Ballads, as the best-known, most readily available, and on the whole most authoritative collection. At the same time no effort has been made to scrutinize very carefully the canon. The battle of the ballads is not our battle. Trojan and Tyrian are alike to the metrist. Be a poem Christmas carol, song, border ballad, minstrel ballad, or ballad par excellence, there is no necessary peculiarity of its meter, and the evidence here presented will go to show that as a whole Child's material is indeed reducible to a single metrical norm. The few exceptional cases will be pointed out in their places, but in general examples can be drawn indiscriminately from any of the different types.