The _Libros de Fabrica_, in which are recorded items bearing on the economic side of church administration, are usually less important; still they contain data that should not be neglected, for very often minor points deserve as much attention as salient ones. Unfortunately the church records of the period prior to 1680 have well-nigh disappeared from New Mexico, but some still exist at El Paso del Norte (Juarez), Chihuahua, that date back to the middle of the seventeenth century. The absence of these records may be somewhat overcome by another class of ecclesiastical documents, much more numerous and more laborious to consult. In fact I am the only one who thus far has attempted to penetrate the mass of material which they contain, although my researches have been far from exhaustive, owing to lack of support in my work. These documents, commonly called "Diligencias Matrimoniales," are the results of official investigations into the status of persons desiring to marry. From their nature these investigations always cover a considerable period, sometimes more than a generation, and frequently disclose historical facts that otherwise might remain unknown. These church papers also, though not frequently, include fragments of correspondence and copies of edicts and decrees that deserve attention. The destruction of the archives and of writings of all kinds in New Mexico during the Indian revolt of 1680 and in succeeding years has left the documentary history of the province during the seventeenth century almost a blank. Publications are very few in number. There is no doubt that the archives of Spain and even those of Mexico will yet reveal a number of sources as yet unknown; but in the meantime, until these treasures are brought to light, we must remain more or less in the dark as to the conditions and the details of events prior to 1692. A number of letters emanating from Franciscan sources have been published lately in Mexico by Luis Garcia y Pimentel, and these throw sidelights on New Mexico as it was in the seventeenth century that are not without value. In the manuscripts from the archives at Santa Fe that survived the Pueblo revolt, now chiefly in the Library of Congress at Washington, occasional references to events anterior to the uprising may be found; and the church books of El Paso del Norte (Juarez) contain some few data that should not be neglected. In 1602 there was published at Rome, under the title of _Relacion del Descubrimiento del Nuevo Mexico_, a small booklet by the Dean of Santiago, Father Montoya, which purports to give a letter from Onate on his occupancy of New Mexico and journey to the Colorado river of the West, thus covering the period between 1597 and 1605. It is preceded by a notice of Espejo's exploration, but it is entirely too brief to afford much information. The little book is exceedingly rare; but three copies of it exist in the United States, so far as I am aware.