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As Archimedes settled into his evening bath and noticed that the water level rose, he accidentally realized that water displacement relates to volume. He proclaimed "Eureka!" Since that day and more regularly in modern times, some of the most impactful scientific discoveries have occurred by accident.
Let's review just a few of the important discoveries of the past couple of centuries that were made entirely by chance.
In 1791 Luigi Galvani was an anatomist at the University of Bologna. Galvani was investigating the nerves in frog legs, and had threaded* some legs on copper wire hanging from a balcony. Once a puff of wind caused the legs to touch the iron railing. A spark snapped* and the legs jerked violently (even today, we speak of being "galvanized" into action). In one unintentional step, Galvani had observed a closed electrical circuit, and related electricity to nerve impulses. So he is typically credited with the discovery of bioelectricity.
In 1879, Louis Pasteur inoculated some chickens with cholera bacteria. It was supposed to kill them, but Pasteur or one of his assistants had accidentally used a culture from an old jar and the chickens merely got sick and recovered. Later, Pasteur inoculated them again with a fresh culture that he knew to be dangerous, and the chickens didn't even get sick. Chance had led him to discover the principle of vaccination for disease prevention.
Wilhelm Roentgen was experimenting with electrical discharges one evening at the University of Wurzburg in 1895. There was a screen coated with a barium compound lying to one side, and Roentgen noticed that it would fluoresce when an electrical discharge would occur in the tube he was watching. On reaching for the screen, Roentgen got his hand between the discharge tube* and the screen and saw the bones of his own hand through the shadow of his skin. In 1901, Roentgen received the Nobel Prize for his accidental discovery of X-rays.
Alexander Fleming was a young bacteriologist at St. Mary's Hospital in London in 1928. One day in his cluttered laboratory, he noticed that a culture dish of bacteria had been invaded by a mould* whose spore must have drifted in through an open window. Under the microscope, he saw that, all around the mould, the individual bacteria that he had been growing had burst. He saved the mould, and from it produced the first penicillin.
Although the mad scientists or eccentric inventors so often portrayed in old movies are still good for laughs, that's not what we're talking about here. Surely the need still exists for the imaginative and inventive experimenter.
(Adapted from “Unexpected scientific discoveries are often the most important” by Larry Gedney. Alaska Science Forum, 1985)
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*to thread - здесь нанизывать
*a spark snapped – здесь проскочила искра
*a discharge tube – здесь газоразрядная трубка
*mould - здесь плесень
4. Explain what the highlighted words and expressions mean. Use a dictionary or consult your teacher if necessary.
5. Here are some answers. What are the questions?
Example: Q ___ When and where was Luigi Galvani doing his investigations?
A In 1791 at the University of Bologna.
a) Q __________________________________________________________?
A A puff of wind.
b) Q _________________________________________________________?
A To nerve impulses.
c) Q __________________________________________________________?
A Louis Pasteur.
d) Q ___________________________________________________________?
A With electrical discharges.
e) Q ___________________________________________________________?
A Barium compound.
f) Q ___________________________________________________________?
A The bones of his own hand.
g) Q __________________________________________________________?
A The Nobel Prize.
h) Q ___________________________________________________________?
A Bacteriologist.
i) Q ___________________________________________________________?
A The first penicillin.
6. Sum up in your own words how these discoveries were made.
| a) bioelectricity | c) X-rays |
| b) vaccination | d) penicillin |
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