Justin Smith wrote, in 1919, what is regarded as the best source of information on the war with Mexico. This is not to say that his book is perfect and errors do appear.
Heitman's comprehensive work, first published in 1903, is likewise regarded as an excellent souce of information. It also has some errata with the folds.
On page 511 of volume II, Smith had this to say about the casualty and desertion figures that were previously published. "The earlier statements issued by our government were in many instances incorrect." His figures were taken from the 1849 report of the adjutant general.
Contrary to popular belief, the Antebellum Army kept accurate records of everything from camp kettles to picket pins. Thus, a clerk sitting at the War Department could tell you the number of blankets issued to a given company when it left Jefferson Barracks for Texas in 1845. The spelling of names is oft-quaint, but monthly company returns and muster rolls give us accurate accounts of how many men took french leave during a given time period.
The figures cited in the 1848 report and later, unfortunately by Heitman and Bauer (excellent sources in most things about the war) were, in my mind, a quick summary rushed to appease congress, but based upon conjecture and incomplete reports.
In short, Bauer goofed in his description of the Battle of Santa Cruz de Rosales (see New Mexico Historical Review Volume 81, Number 4 Fall 2006) and he also goofed by citing the wrong government report.
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