In the correspondence between Johnston and the Confederate government regarding the numerical force of his army, he naturally emphasized his inferiority to Sherman in numbers as an explanation of his cautious defensive tactics and his retreating movements. The introduction into the Southern returns of a column of "effectives" as distinguished from the number of officers and men "present for duty," [Footnote: _Ante_, vol. i. p. 482.] led to a habitual underestimate by their commanding officers. On several occasions Johnston defended his conduct of the campaign by asserting that his army was less than half the size of Sherman's, [Footnote: Official Records, vol. xxxviii. pt. iv. p. 795.] and this necessarily led to an examination of his returns. These regular numerical reports are of course the ultimate authority in all disputes, and we find the Richmond government doing just what the historian has to do,--comparing the estimates of the general with his official returns. Officers of all grades and of the highest character fall into the error of memory which modifies facts according to one's wish and feeling. Thus at the beginning of this campaign we find General Bragg, speaking for the President, saying that General Polk's "estimates and his official returns vary materially." [Footnote: _Id._, vol. lii. pt. ii. p. 659.] Nobody could be freer from intentional misstatement than the good bishop-general. We find the same discrepancies at the East as well as the West. Lee, Jackson, Longstreet, and their subordinates fall into the same error. It is therefore the canon of all criticism on this subject, that nothing but the statistical returns in the adjutant-general's office shall be received as proofs of numbers, though, of course, the returns must be read intelligently.