(70) Young Ehrlich had always aspired to be a doctor, and at medical school he had studied with many famous professors. Ehrlich used to say of infectious diseases: “To kill them, we must shoot with magic bullets!” Therefore, people called him “the fantasy doctor”.

(71) Ehrlich was determined to make the fantasy a reality. He found a lab, bought just enough medical books to bury himself in, and worked hard to find the magic bullet which would kill bacteria without harming human body tissue.

(72) While he was reading, he was smoking a strong cigar and kept a record of what he thought. On the floor, in the cuffs, on the soles of shoes, even on other people's shirts, there were chemical formulas he wrote down.

(73) Ehrlich decided to use chemical methods to invent magic bullets. He, along with a Japanese assistant, took a trypanosoma as an object and carried out numerous monotonous and boring experiments on lab mice. But all the experiments failed.

(74) Once, Ehrlich learned that a deadly sleeping disease was prevalent in Africa, as the result of trypanosomas entering human blood. With the treatment of the atropine, trypanosoma could be killed, but patients would be blind.

(75) This discovery aroused Ehrlich's interest. He wanted to change the chemical structure of atropine and eliminate the composition that may deal damage to the optic nerve. This time, scientists from many different countries joined him and the team enlarged a lot.

(76) The experiment went on intensely, and sometimes Ehrlich had to take a nap on the bench in the lab, and then he would continue his work. In order not to forget his family's birthdays, he even had to send a letter to himself a few days before their birthdays to remind himself.

(77) It took Ehrlich more than two years to change the chemical structure of atropine again and again. Finally, He developed a “magic bullet”, which could be “shot” to kill the trypanosoma without damaging human tissues.

(78) Ehrlich named the effective drug “606” (arsfenamine) and successfully used it to treat syphilis patients. At the end of 1910, Ehrlich was warmly welcomed by the people when he attended the Koerner Fort Scientific Congress.

(79) Ehrlich and his colleagues received reports of the therapeutic effect of 606 from all over the world, but they were not complacent for the achievements. After countless failures, they invented “914” (neoarsphenaminum), which was safer than 606.