Final answer:
Patrick's strategy for sustaining the fire involves building a solid foundation with dry wood and feeding the flame in increasing twig sizes, adhering to crucial survival knowledge in harsh temperatures.
Step-by-step explanation:
Patrick's great idea for keeping his fire burning longer involves methodically building a stable foundation for the fire, starting with dry firewood sticks and twigs placed on top of the snow. This foundation keeps the young flame from being extinguished by the melting snow it would otherwise create.
He then successfully ignites the fire using a shred of birch bark and gradually feeds it with growing sizes of twigs, starting from the smallest up to the size of his fingers. As the flame strengthens, he adds larger twigs and branches, ensuring that the fire grows steadily in intensity.
This careful and step-by-step approach is crucial for survival in the subzero temperatures of the Klondike, where even a single failure in building a fire can have deadly consequences when one's feet are wet and freezing.
Patrick must not fail in his first attempt to build a fire because this is a matter of life and death in the extreme cold.
His understanding of the necessity comes from the advice of an old-timer, which he recalls as he manages to sustain the fire. With the fire going strong, he can finally remove his wet foot-gear to dry it by the heat, ensuring his safety from frostbite.