$~~~~$Scientific discovery can take various forms. One of them is “serendipity,” the luck of finding valuable things unintentionally. Serendipity was at work when Alexander Fleming discovered penicillin, the antibiotic miracle.
$~~~~$Fleming had long been known for having an untidy laboratory. One morning in 1928, this 16 proved very fortunate. It was his first day coming back to work after a long vacation. Before the vacation, he 17 in the sink a number of petri dishes in which he had been growing bacteria. While he was sorting through the long 18 dishes of germs that morning, he observed that some of the dishes were contaminated with a fungus, which had ruined his experiment. He was about to 19 the dishes, but he noticed that in one dish, the bacteria had failed to grow in the area around the fungus. This accidental finding gave rise to subsequent research that led to the discovery of penicillin—a drug that has since saved millions of lives.
$~~~~$Chance 20 , however, may not be enough to make key discoveries like this. The scientist must have a prepared and open mind to detect the importance of the unforeseen incident and to use it constructively.