they could improvise. The mound was where the charcoal was made.

It was heart-breaking work to keep the fires going with charcoal,
because it burned so rapidly in the powerful draft of the furnaces,
but the original fire-room gang had been recruited to several
times its original number from among the towerites, and the work
was divided until it did not seem hard.

As Estelle looked down two tiny figures sauntered across the clearing
from the woods with a heavy animal slung between them. One of them
was using a gun as a walking-stick. Estelle saw the flash of the
sun on its polished metal barrel.

There were a number of Indians in the clearing, watching with
wide-open eyes the activities of the whites. Dozens of birch-bark
canoes dotted the Hudson, each with its load of fishermen,
industriously working for the white people. It had been hard to
overcome the fear in the Indians, and they still paid superstitious
reverence to the whites, but fair dealings, coupled with a constant
readiness to defend themselves, had enabled Arthur to institute a
system of trading for food that had so far proved satisfactory.

The whites had found spare electric-light bulbs valuable currency in
dealing with the redmen. Picture-wire, too, was highly prized. There
was not a picture left hanging in any of the offices. Metal
paper-knives bought huge quantities of provisions from the eager
Indian traders, and the story was current in the tower that Arthur
had received eight canoe-loads of corn and vegetables in exchange
for a broken-down typewriter. No one could guess what the savages
wanted with the typewriter, but they had carted it away triumphantly.