In addition to Cao Chong's image, Aptom is high flyers of Princeton University. After graduation, he was arranged to work with Edison. He is very dissatisfied with Edison who relies on self-study without a diploma, and often shows a sarcastic expression. However, a little thing changed his attitude towards Edison fundamentally. Once, Edison asked Aptom to calculate the volume of pear-shaped glass bubbles, and Aptom nodded, thinking about such a simple thing for a while. I saw him bring pear-shaped glass bubbles. I measured it up and down several times with a ruler, and then drew a sketch on the paper according to the style, and listed a formula. After calculating it, I still didn't figure it out. In a row in dozens of formulas, or no results, Aptom was flushed, flustered. Edison waited in the laboratory for a long time, but he was surprised to see no results. He went to Aptom's workshop and saw many formulas on several pieces of white paper. He smiled and said, "It's a waste of time for you to calculate like this.". I saw that Edison brought some water, poured it into the glass bubble and gave it to Aptom, saying, "Find another measuring cylinder and you will know the answer." Aptom was enlightened and finally admired Edison, and finally became a good assistant in Edison's career.