There is conclusive evidence that at no period during the war has the Confederacy had more than three hundred and fifty thousand effective men in the field, and it has no power to carry that number beyond four hundred thousand. The population of the Union, by the census of 1860, was thirty-two millions. At the usual rate of increase it now amounts to thirty-four millions; of these, four millions are blacks, and of the residue, twenty-six millions are in the loyal districts, and but four millions in the Confederacy, if we exclude New Orleans and those portions of Virginia and Tennessee which have been subdued by the Federal arms. In our Northern States the militia has rarely exceeded ten per cent. of the population. At least one-half of the population is composed of females; one-half of the residue is below the age of sixteen. If we deduct from the remainder three-twentieths for those below eighteen, those above forty-five, and those exempted by law or infirmity, one-tenth alone will remain. It is said that the Confederacy has called out all the white males between sixteen and thirty-five, and proposes to summon all those between thirty-five and fifty. If it does so, we may well expect such forces to break down in heavy marches or suffer from exposure. But let us assume that it can bring into the field fourteen per cent. of its entire population--(and we must not forget that this is a high estimate, as all the able-bodied men of Massachusetts are but twelve per cent. of her population, or one hundred and fifty-five thousand): upon this assumption, the effective force of the Confederacy at the start was but five hundred and sixty thousand, and if to this we add forty thousand more for volunteers and conscripts from Maryland, Missouri, Kentucky, and East Tennessee, we have a capacity for six hundred thousand only. Of these there has been a continual waste from the outset by sickness, desertions, capture, and the casualties of war. The Union army has lost at least one-third, and been reduced from six hundred thousand to four hundred thousand by such depletion; and in the same ratio, the South, with inferior supplies and stores, and with greater exposure, must have lost at least an equal number. In estimating its present capacity at four hundred thousand men, we undoubtedly exceed the actual resources of the South. To meet this we have at least four hundred thousand effective men now in the field, to be increased to a million by the new levies, and soon to be aided by thirty mail-clad steamers added to our present fleet on the ocean and the Mississippi,--a naval force equivalent to at least two hundred thousand more.