Robert Boyle – Boyle’s Law

In our new Manufacturing Disruption series, we highlight groundbreakers past and present who have made scientific and engineering breakthroughs that affect manufacturing. 

Boyle’s Law

Boyle's Law

Robert Boyle by Johann Kerseboom, circa 1689.

Robert Boyle was a 17th century Renaissance man, dabbling in theology, inventing and philosophy. His work in physics and chemistry, however, yielded him the most fame, specifically for Boyle’s Law.

Boyle, though fostered as a child to a local family in Ireland, was born into wealth as the seventh son of the eventual first Earl of Cork. His father’s connections landed him private tutors. This education contributed to Boyle’s interest in science. As he grew older, his travels continued his growth as a scientific researcher. He joined other philosophers in the Invisible College, a group seen as a precursor to the Royal Society of London.

Help from friends

The inspiration for what would become known as Boyle’s Law came from the work of two of Boyle’s contemporaries, Richard Towneley and Henry Power. Towneley and Power had used a barometer – a relatively new invention at the time – to measure the pressure of air at different altitudes on a hill. The pair found an inverse relationship between the density of air and its pressure. Towneley is said to have discussed this finding with Boyle, who then conducted experiments to test what he called “Mr. Towneley’s hypothesis.”

Boyle’s experiments confirmed what Towneley and Power had found: The pressure and volume of a gas, when held at a constant temperature, are inversely proportional. This means that when the volume of a container decreases, the pressure of the gas inside that container will increase. Mathematically: PV=k, where P is the pressure, V is the volume and k is a constant. The equation depends on a closed system at a constant temperature. To compare the same gas at different conditions, P1V1 will equal P2V2.

Although Power and Towneley’s work preceded Boyle’s, Boyle published first, leading to the law bearing his name.

While Boyle received the credit, Towneley and Power weren’t the only ones who contributed. It was his assistant, the soon-to-be-famous Robert Hooke, who reportedly set up the experiments.

Proportion-Air tips our hat to Robert Boyle. We rely on his law to calculate the flows, compression ratios and pressures required to meet the demands of our customers’ applications.