Early in November came one of those cold rain-storms that mark sharply the end of Indian summer which often prolongs the warm season far into autumn.
It was the first day that all four campers stayed in the shack, which the trapper and the Indian had during the preceding week transformed into a real cozy cabin. Chunks of ash, elm, maple, and cottonwood slowly burning in the old sheet-iron stove which Barker had set up in the middle of the room kept the cabin dry and warm, while the large spattering drops of rain beat a tattoo on the roof.
The few stray leaves that had until now adhered to their branches were swept away. The river-bottom trees assumed their sharp, undraped silhouettes of winter, and from the bluffs all the bright autumn colors had vanished.
The summer birds had gone. Only a few hardy chickadees, woodpeckers, and nuthatches that defy even the coldest northern winter had remained behind the migrating hosts.
By the middle of November the lake was frozen over.
With the beginning of cold weather little Tim’s health rapidly improved. Soon he was strong enough to go sliding on the ice; and when Barker had a blacksmith at the landing make a pair of skates for each of the boys the joy of the lads was unbounded.
They skimmed lightly over the frozen sloughs, where the trees and banks sheltered them from the wind. From these trips they returned with flushed cheeks and ravenous appetites and many stories of what they had seen.
They had chased pickerel and other fish under the clear ice, they had seen a muskrat swim along with an air bubble attached to his nose, and they had watched clams slowly plowing their furrow in the sand as they withdrew from the shallower banks into deep water.
The Mississippi and its tributaries harbor a large variety of clams whose shells are now used for pearl buttons. The boys were curious about the habits and life of these quiet creatures that were always nearly buried in mud and sand and moved about by queer little jerks. When Tim was still too weak to move about much, he had amused himself for hours dropping clams, which Bill had caught, back into the water, and watching how each shell, slowly opening, put out a sort of white, fleshy foot; slowly righted itself, and crawled away into deep water.
