Thorin was looking for a lost temple in the Western Ghats forest with his team of archaeologists when he got separated from the group. He didn't have any maps or a compass with him at the time, so he was in deep trouble being lost in the middle of a forest. All he had were lots of vegetables and fruits like carrots, beets, corn, potatoes, pumpkins, bananas, apples, and melons. After seeing them, he realized that all of them were high-sugar vegetables and fruits. Suddenly, he had an idea. He also had a couple of balloons and some plastic containers. He put all his vegetables and fruits into the container and sealed it so that no air could pass inside, allowing methane gas to be produced. He knew that it would take at least two days for the required methane gas to be produced, so he kept some fruits for himself to eat during those two days. During this time, he made a bow and some arrows. Then he built a fire by filling a plastic cover with water and shaping it into a sphere; using it like a convex lens, he concentrated the sunlight on the tinder. Then he ripped a part of his shirt and bound it to the arrowhead end of the arrow. In the evening of the third day, he filled the three balloons with methane gas using tubes so that the gas wouldn't come into contact with the air. Since methane gas is lighter than air, the balloons started to rise, and right when the balloons were about to go out of sight, he dipped the arrowhead into the fire, and after it started burning, he released the arrow from his bow so that the burning arrow hit the balloon and the balloon burst because of the reaction between the fire, methane gas, and oxygen, producing light and sound. His friends, who were searching for him, saw the light and heard the sound and rushed in its direction, and Thorin was rescued.