This is one of the three bishoprics of the island of Luzon. It includes the provinces of Cagayan, Nueva Vizcaya, Pangasinan, Union, Ilocos Sur, Ilocos Norte, Abra, and the Batanes Islands. This diocese extends throughout the northern part of the island, from longitude 123 deg. 21' on the western coast, where the point called Pedregales is located, to 126 deg. 5' on the eastern or opposite coast, where the point Maamo projects; and from latitude 16 deg. 17 to 18 deg. 38'. It is bounded on the south by the archbishopric of Manila, to which belong the provinces of Zambales and Pampanga, on the extreme west and northeast. On the southeast it descends to latitude 15 deg. 30', to point of Dicapinisan and to Nueva Ecija, with that of Nueva Caceres or Camarines in the upper limits of the province of Tayabas. It is also bounded on the east by the archbishopric [of Manila] in the above-mentioned province of Nueva Ecija. Its boundaries on the west and north are maritime. Beginning where this last province ends (which may be considered as the point of Dicapinisan), the opposite coast offers nothing more noteworthy than the bays of Dibut and Baler until one reaches that of Casiguran; and there is nothing worthy of mention. When one leaves this last bay, he must double the cape of San Ildefonso, where the ancient ecclesiastical jurisdiction of this bishopric began. Continuing north for a matter of some sixteen nautical leguas, one meets the port of Tumango, the safest and most capacious of all this rough coast. A short distance from that port are found the village of Palanan and the missions of Dicalayon, and Dauilican or Divilican. Thence, until one reaches the cape of Engano, [123] one finds nothing more than some small anchoring-places, which offer but scant refuge to the vessels, as they are all exposed to the vendavals. On the northern coast as well, which begins at the said cape of Engano (so called because of the deceitfulness of its currents), one does not meet bay or port until he reaches the village of Aparri, some fifteen leguas away. This village is located a short distance from the ancient city of Nueva Segovia, which is known to the natives under the name of Laen [sc. Lal-lo]. A matter of fifteen leguas more from the above village of Aparri, is encountered the beginning of the Caraballos mountains, whose point, called Balaynacira, or Pata, projects into the northern sea and is the most northern point of the island. At this point ends the province of Cagayan, and begins that of Ilocos Norte, in the village of Pancian which is nine hours' distance from that of Bangui. Then one doubles the cape of Bojeador, where the western coast of the island begins, and passes the provinces of Ilocos (Norte and Sur), Union, and Pangasinan, which abound with many villages, until the cape of Bolinao is reached--where this bishopric is bounded by the archbishopric, to which belongs the province of Zambales.