Daniel Bernoulli
By: Jeffrey Hu

Daniel Bernoulli was born in a family of talented mathematicians. His father was Johann Bernoulli. Daniel Bernoulli was born on February 8, 1700in Groningen, Netherlands. Though he was born in Groningen, when he was five, he and his family moved to Basel, Switzerland. In Basel, Johann II Bernoulli was born as Daniel Bernoulli’s younger brother. Daniel Bernoulli was the oldest of three. Though all three brothers would study mathematics, Daniel Bernoulli’s father tried to force him to go into business but he resisted and wanted to study mathematics. Johann Bernoulli agreed only so much to send he to be a doctor saying there was no money in mathematics. Daniel Bernoulli agreed.
Bernoulli spent time studying medicine and went to Heidelberg in 1718 and Strasbourg in 1719. Eventually Bernoulli came back to Basel in 1720 and completed his doctorate in medicine. By now, Johann Bernoulli began teaching his son more mathematics. Daniel Bernoulli learned about his father’s kinetic energy theories and applied his knowledge of conservation of energy to his medical studies. Bernoulli wrote his doctoral paper on the mechanics of breathing. He used mathematical physics to get his medical doctorate.
Daniel Bernoulli wanted an academic career as a professor like his father but when he applied for chair of anatomy and botany, and chair of logic, he lost. Then Bernoulli went to Venice to study medicine. In Venice, Bernoulli became sick but even so he published his first work in 1724. The mathematic work was called Mathematical Exercises which contained four parts:
· The game of faro
· The flow of water form a hole and Newton’s theories
· Riccati differential equation
· Geometry question concerning figures bounded by two arcs of a circle

The game was not important at all except for the fact that he studies probability in Venice. Daniel Bernoulli had not solved problems with pressure but his medical work with blood vessel provided him with motivation and interest to continue.
Also while in Venice, Daniel Bernoulli designed an hourglass that could still keep accurate time even at sea. He submitted this to the Paris Academy and combined with his Mathematical Exercises, he was offer a chair of mathematics in St. Petersburg, Russia. His brother Nicholaus II Bernoulli was also offered a chair. They traveled to St. Petersburg in late 1725. Unfortunately, in eight months, his brother died of a fever. Bernoulli was devastated and thought about returning home to Basel. His father Johann Bernoulli was able to send his best student, Leonard Euler to help Bernoulli in 1727. The following time period was Bernoulli’s most productive part of his life.
While in St. Petersburg, he made an important discovery on frequency of the oscillations of a system like in the strings of an instrument was made of infinite vibrations on the string. A second important work was one on probability. Basically he said that the expected increase in value is the product of the odds of the gain and the value of the gain. This would tell someone what decisions to make whether in numbers or in real life. The most important work Bernoulli did was titled Hydrodynamica though he would not publish this until 1738. This work had the first correct analysis of water flowing from a hole. This was based on the conservation of energy principles he learned earlier in his life. Bernoulli also talked about pumps and other machines to raise water. He provided the basic laws in theories of gases.
Despite all the accomplishments Daniel Bernoulli made while working with Euler, his was still not happy in St. Petersburg. In 1931, Bernoulli began applying for posts in Basel but yet again lost. In 1934, Daniel Bernoulli entered in the Grand Prize of the Paris Academy but his father Johann Bernoulli also submitted an entry. Their entries were judged equal and father and son with jointly awarded the Grand Prize. This however had bad consequences for Daniel Bernoulli. His father refused to think of his son has his equal and so their relations fell apart. Daniel Bernoulli was banned from his father’s house even though he was in Basel again. Though the reason is unknown, after this, Bernoulli's interest in mathematics waned.
Even though Daniel Bernoulli was not in St. Petersburg, he kept in relation to Euler and still made a great team together. Bernoulli continued to polish his Hydrodynamica and added a chapter about the force of a jet of water on an inclined plane and its reaction. Hydrodynamica was published the next year. The following year his father published Hydraulica and faked the publication date to make it look like Daniel Bernoulli was plagiarizing him when it was the other way around. This shows how bad their relationship is. Daniel Bernoulli tried to med the relationship by adding, “Daniel Bernoulli, son of Johann”.
Bernoulli continued to teach at Basel and was appointed chair of physics in 1750. He gave amazing lectures with great demonstrations. In total, Daniel Bernoulli won the Grand Prize of the Paris Academy ten times. He made important contributions to physics and Newton’s theories. Daniel Bernoulli was honored in his lifetime had lead several scientific groups in his time.

Interesting Fact
One interesting fact about Daniel Bernoulli is that when he and his father jointly won the Grand Prize, his father shunned him and refused to think of Daniel as his equal. Aren't parents suppose to be supportive and proud?