In most cases it will not be difficult to determine where the MS. sources are preserved. Despatches to or from a military or naval officer, a diplomatic or a consular agent may be understood, if there is no indication to the contrary, to be in the corresponding archives of the government addressed. (The connection of the author of a despatch may be ascertained by looking up his name in the index.) This direction may seem vague, but the officials at the archives will be found able to supply the needful details. The principal foreign agents in Mexico were (U. 8.) Poinsett, Butler, Ellis, Thompson, Shannon, Slidell, and (consuls) Jones, Black, and Dimond; (England) Morier, Ward, Pakenham, Ashburnham, Bankhead, Doyle, Thornton, and (consul) Giffard; (France) Coch. let, Martin, Deffaudis, and Cyprey; and (Spain) Bermúdez de Castro and Lozano. Mexican documents cited in the form "To 8. Anna, Apr. 20" or "S. Anna, Mar. 4," are in the archives of the War Dept. of Mexico, National Palace. Many unofficial letters can readily be traced by means of the list of MS. sources. When it has seemed desirable, however, particularly at the beginning of a chapter, heavy figures referring to that list have been prefixed to the citation, and also to many citations of official documents. The MS. sources are given in the appendix of each volume; the printed sources in the appendix of the second volume.
A formula like "Ho. 60; 30, 1"? means House Executive Document no. 60, of the Thirtieth Congress, first session; and "Cong. Globe, 30, 2" refers to the Congressional Globe, Thirtieth Congress, second session. In some cases it has been found best to cite a document broadly by mentioning the first page of it; and the same remark applies to passages in other publications. The year in the date of a cited document is omitted when it is the same as that of the events referred to in the corresponding paragraph of the text. E.g. a document dated Oct. 15, 1847, attached to a paragraph dealing with Scott's landing at Vera Cruz (March, 1847) or capturing Mexico City (Sept., 1847) is cited as of "Oct. 15," not "Oct. 15, 1847." This is done to save space. The abbreviations are plain. "Gov." means governor; "comte. gen.," comandante general; "comte. mil." comandante militar. "Gov. Puebla," etc., means governor of Puebla, etc. "Diario" means the official newspaper. For fuller titles of books the list of sources may be consulted.
The want of definiteness and the lack of statistics in numerous cases (particularly Mexican affairs) may be charged to a dearth of trustworthy data.
