Will, you have made an interesting observation to say the least, you may in fact have discovered a significant error in some time-honored numbers.
I'm not very knowedgeable personally in the Mexican War, so I guess you can consider me uninformed but curious, and you could even ask "What right do you have to comment at all?" and that's a fair question. My only excuse is that I've enjoyed reading about he Mexican War from time to time.
One of my favorite books on the subject is K. Jack Bauer's "The Mexican War," MacMillan 1974. On pp. 397, in table 2, Bauer has the following tallies for desertion:
He lists several sources underneath the table, including S. Ex Doc 36, 30th Cong, 1st sess, 6-7; Scott, "Military Dictionary," 645-49; Kreidberg and Henry, "History of Military Mobilization," 78, Heitzman, "Historical Register..." II, 282.
If I had to pass an impartial judgment at this point, and I know very little about the subject, I'd be a bit more inclined to go with Bauer's numbers since I can see his documentation listed here in front of me.
It is encouraging that you've done some work to check these numbers, and I think it would help if you could post the sources used by the author you mention, to give us a better means of comparison. I don't have his book so I'm helpless to do so.
Do you know if his book was published subsequent to Bauer's, so he had a chance to check Bauer's numbers and correct them? Does he cite Bauer? Is he held in as high a regard as Bauer is? I really don't know the answers.
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