The diminishing of the glory of Assyria will be such that little will remain of their "forest," or their peoples. There would be so few that a child would be able to count them. The image is that of a child less able in the art of writing. The child might not be able to count very high, and certainly would not have the skill to write larger (and therefore unfamiliar and unpracticed) numbers. While we might wonder at this, it should be remembered that in the Hebrew system, there were no numbers. As with Greek (and to an extent, Roman) numerical system, letters served to mark the numbers. Our numerical system is take from the Arabic system, with which these cultures were unfamiliar. Thus larger numbers were not simple cases of the addition of more zeroes, but different letters and conventions.