The armies which were in the field in the early part of the war bear very various relations to the countries from which they come.
Great Britain had upon the Sambre in the first battle of the campaign rather more than one-tenth per cent. of her total population. The French had in the field at the outset of the war 5 per cent. of their total population, the Russians 1 per cent., the Germans perhaps 5 per cent., the Austrians between 3 and 4 per cent., the Serbians quite 10 per cent.—and 10 per cent. is the largest total any nation can possibly put into the field.
Now the chances of growth for each of these contingents were very different in each case.
That of Great Britain was indefinitely large. Given sufficient time, sufficient money, and sufficient incentive, Great Britain might ultimately put into the field two million or even three. She was certain of putting into the field in the first year of the war more than one million; she might hope to put in two. She had further behind her as a recruiting field, the Colonies, and—a matter of discussion—the Indian Army.
The French had nothing to fall back on save the young men who were growing up. Therefore, they were certain not to be able to add to their numbers for at least six months, which is just about the time it takes to train effectively new formations.
The Germans had in reserve about as many men again as they had put under arms at the beginning of the war. If the French could hope for a grand total of four millions wherein somewhat over three might be really effective and of useful age for active service in any shape, then Germany might hope to produce a grand total of somewhat over seven millions and a similar useful body of over five, for the German adult males are to the French as more than five to three.
Austria could in the same way call up a reserve somewhat larger in proportion than the Germans, but as her population was somewhat smaller than Germany, we must write her down for something over four millions instead of something over five, for a grand total of between five and six millions instead of for a grand total of seven.
Serbia, like France, could not increase her contingent save by calling up her younger men; and her army was, like that of the French, a fixed quantity, at any rate for the first six months of the war, and increased by one-tenth or less when the new class was trained.
Russia in her turn presented yet another type of growth. She had by far larger reserves of adult males than any other Power, and was practically equal, in the material of which one can ultimately make trained soldiers, to Germany and Austria combined; theoretically, counting all her various races, she was the superior of Austria and Germany combined. But it was certain that she could not equip more than a certain number in a given time, or train them, or officer them, or govern them.
I think it just to say that she certainly could not put into the European field more than five millions during the better part of the first year of the war. Though it must be remembered that if the war lasted indefinitely she would have at her back at any period indefinitely large reserves to draw upon.