Note 1 — Expeditions to the Province of Tuy

The route of this expedition was evidently up the Rio Grande de Pampanga, northward through the present provinces of Pampanga and Nueva Ecija; the headwaters of this stream are separated by the ridge of Caraballo Sur from those of the Rio Grande de Cagayan. Crossing these mountains, the Spaniards found themselves, at the southern end of Nueva Viscaya, at the sources of one of the two great branches of the latter river, the Magat River—the one which is named Tuy in our text. It joins the main stream of the Rio Grande de Cagayan, a few miles above Ilagan, in the province of Isabela, and the united streams flow northward through the entire length of that province and of Cagayan, falling into the sea below Aparri, on the northern coast of Luzón. See the short account of this expedition given in Vol. VIII, pp. 250, 251.