September in Peiping is supposed to be the time when the golden breeze blows coolly and the streets are paved with ginkgo trees. However, in the autumn of the 26th year of the Republic of China, the air in the old capital is filled with gunpowder smoke and anxiety. The white marble pillars at the second gate of Tsinghua University still retain traces of the hooves of the Japanese cavalry yesterday. The sound of reading in the past was torn apart by the sporadic gunfire from the Marco Polo Bridge in the distance, and scattered on the stone road full of fallen leaves.
Lin Mo carried a bulging blue cloth bag on his back and walked quickly across the lawn in front of the I-shaped hall. Wrapped in the bag was the "General Theory of Electromagnetism" which he regarded as a treasure, several volumes of handwritten experimental data, and two single garments sewn by his mother overnight. He had just come out of the physics department laboratory. The cuffs of his white shirt were stained with rosin, and there were fine beads of sweat on his forehead. His eyes were as sharp as an eagle, and he scanned the surroundings vigilantly.
"Lin Mo! Wait for me!"
There was a hurried shout from behind. Lin Mo turned around and saw his classmate Zhao Lei running towards him panting, holding a heavy wooden box in his hand, his face flushed. "I've finally caught up with you. Professor Zhou asked me to give this to you. He said it must be hidden well so it doesn't fall into the hands of the Japanese."
