Vi Author’s Preface 
documents, deserving of particular mention, may be found in bundles that are 
here passed over in general terms, and vice versa. 
Moreover, I can not hope to have exhausted the resources of the Mexican 
archives or even of those which I examined. The discovery of historical 
materials, particularly by a foreigner in a country where historical studies and 
archive science are in their infancy, is often the result of accident, however 
much of systematic search and inquiry may be devoted to the task. Conse- 
quently it is probable that important things which I have overlooked will be 
brought to light in the very places where I have worked. Materials which at 
the time when I made my investigations were in such a condition as to pre- 
clude their proper examination—and they were not a few—will be put in 
order, and may yield important documents to future investigators, while large 
groups of manuscripts which seemed to promise relatively too little to war- 
rant examination within the time available may prove to have rich contents. 
Some archives which presumably contain valuable material for the history of 
the United States were consciously passed by simply for lack of time. Other 
repositories, public or private, which were unconsciously missed, are quite 
certain to come into notice later. 
In short, it is requested of users of this book that they view it as in the 
nature of a preliminary report, based upon what was actually found, prepared 
wholly for utilitarian purposes, and not regarded by the compiler as in any 
sense a definitive treatise on the Mexican archives. It may be regarded as a 
compilation of notes, taken by one primarily interested in knowing and record- 
ing the whereabouts and nature of materials for United States history, and 
put in the most convenient form consonant with that purpose. 
Nevertheless, no pains have been spared to make these shortcomings as 
few as possible. And while the book is in no sense a calendar—such a 
work would fill many volumes—and will not relieve the investigator of a more 
minute search, by himself or through the officials of the various archives, it is 
hoped that it will guide the way to and through the principal materials for 
United States history in Mexican archives. 
It has seemed best, in the introductory stage of the exploitation of archives 
so little known as those of Mexico, not to try to treat all archives and parts of 
archives with uniform detail, but to put the emphasis at those points where 
it would count for most, that is, on the collections that are richest in mate- 
rials for the history of the United States. One result of this procedure has 
been to give to half a dozen or more sections the greater part of the space 
devoted to the entire Archivo General y Publico, while similar disparity has 
resulted in other archives. Owing to various circumstances, it has not always 
been possible, even where desirable, to treat with equal emphasis groups of 
documents of equal importance. 
To persons who might turn to this volume for help in the study of the 
history of the present Mexico it should be said that, as its title indicates, the 
