"I know you cannot count beyond ten, so I will tell you. Hold up your two hands. On both of them you have altogether ten fingers and thumbs.

"I know you cannot count beyond ten, so I will tell you. Hold up your  two hands. On both of them you have altogether ten fingers and thumbs.  Very well. I now take this grain of sand—you hold it, Hoo-Hoo." He  dropped the grain of sand into the lad's palm and went on. "Now that  grain of sand stands for the ten fingers of Edwin. I add another grain.  That's ten more fingers. And I add another, and another, and another,  until I have added as many grains as Edwin has fingers and thumbs. That  makes what I call one hundred. Remember that word—one hundred. Now I  put this pebble in Hare-Lip's hand. It stands for ten grains of sand, or  ten tens of fingers, or one hundred fingers. I put in ten pebbles. They  stand for a thousand fingers. I take a mussel-shell, and it stands for  ten pebbles, or one hundred grains of sand, or one thousand fingers...."  And so on, laboriously, and with much reiteration, he strove to build  up in their minds a crude conception of numbers. As the quantities  increased, he had the boys holding different magnitudes in each of  their hands. For still higher sums, he laid the symbols on the log of  driftwood; and for symbols he was hard put, being compelled to use the  teeth from the skulls for millions, and the crab-shells for billions.  It was here that he stopped, for the boys were showing signs of becoming  tired. "There were four million people in San Francisco—four teeth." The boys' eyes ranged along from the teeth and from hand to hand, down  through the pebbles and sand-grains to Edwin's fingers. And back again  they ranged along the ascending series in the effort to grasp such  inconceivable numbers. "That was a lot of folks, Granser," Edwin at last hazarded. "Like sand on the beach here, like sand on the beach, each grain of sand  a man, or woman, or child. Yes, my boy, all those people lived right  here in San Francisco. And at one time or another all those people  came out on this very beach—more people than there are grains of sand.  More—more—more. And San Francisco was a noble city. And across the  bay—where we camped last year, even more people lived, clear from Point  Richmond, on the level ground and on the hills, all the way around to  San Leandro—one great city of seven million people.—Seven teeth...  there, that's it, seven millions." Again the boys' eyes ranged up and down from Edwin's fingers to the  teeth on the log. "The world was full of people. The census of 2010 gave eight billions  for the whole world—eight crab-shells, yes, eight billions. It was not  like to-day. Mankind knew a great deal more about getting food. And the  more food there was, the more people there were. In the year 1800, there  were one hundred and seventy millions in Europe alone. One hundred years  later—a grain of sand, Hoo-Hoo—one hundred years later, at 1900, there  were five hundred millions in Europe—five grains of sand, Hoo-Hoo, and  this one tooth. This shows how easy was the getting of food, and how men  increased. And in the