The Sia resemble the other pueblo Indians; indeed, so strikingly alike are they in physical structure, complexion, and customs that they might be considered one and the same people, had it not been discovered through philological investigation that the languages of the pueblo Indians have been evolved from four distinct stocks. Sia is situated upon an elevation at the base of which flows the Jemez river. The Rio Salado empties into the Jemez some 4 miles above Sia and so impregnates the waters of the Jemez with salt that while it is at all times most unpalatable, in the summer season when the river is drained above, the water becomes undrinkable, and yet it is this or nothing with the Sia. For neighbors they have the people of the pueblo of Santa Ana, 6 miles to the southeast, who speak the same language, with but slight variation, and the pueblo of Jemez, 7 miles north, whose language, according to Powell’s classification, is of another stock, the Tañoan. [Illustration: Bureau of Ethnology. Eleventh Annual Report PLate II PLAZA, SIA.] The Mexican town of San Ysidro is 5½ miles above Sia, and there are several Mexican settlements north of Jemez. The Mexican town of Bernalillo is on the east bank of the Rio Grande, 17½ miles eastward. Though Protestant missionaries have been stationed at the pueblo of Jemez since 1878, no attempt has been made to bring the Sia within the pale of Protestantism. The Catholic mission priest who resides at Jemez makes periodical visits to the Sia, when services are held, marriages performed, infants baptized, and prayers offered for the dead. The missions at Cia and Jemez were founded previous to 1617 and after 1605. They existed without interruption until about 1622, when the Navajos compelled the abandonment of the two churches at San Diego and San Joseph of Jemez. About four years later, through the exertions of Fray Martin de Arvide, these missions were reoccupied, and remained in uninterrupted operation until August 10, 1680. The mission at Cia, as far as I know, suffered no great calamity until that date. After the uprising of 1680 the Cia mission remained vacant until 1694. Thence on it has been always maintained, slight temporary vacancies excepted, up to this day. The mission of San Diego de Jemez was occupied in 1694 by Fray Francisco de Jesus, whom the Indians murdered on the 4th of June of 1696. In consequence of the uprising on that day, the Jemez abandoned their country, and returned, settling on the present site of their pueblo only in 1700. The first resident priest at Jemez became Fray Diego Chabarria, in 1701. Since that date I find no further interruption in the list of missionaries.[3]