Newton (°N)
The Newton scale is a temperature scale devised by Isaac Newton around 1700. It sets the freezing point of water at 0°N and the boiling point at 33°N. Newton used linseed oil as his thermometric substance rather than mercury. The scale has no modern applications but holds historical significance as one of the earliest attempts at quantifying temperature.
Definition
On the Newton scale, water freezes at 0°N and boils at 33°N at standard atmospheric pressure. To convert Newton to Celsius: °C = °N × 100/33. To convert Celsius to Newton: °N = °C × 33/100. Normal body temperature (37°C) is approximately 12.21°N. The scale uses linseed oil expansion as its basis, making it less precise than mercury-based scales.
History
Isaac Newton described his temperature scale in an anonymous paper published in 1701 in the Philosophical Transactions. He used linseed oil in his thermometer and defined a scale where the freezing point of water was 0 and "blood heat" (body temperature) was 12. The boiling point of water fell at 33 on his scale. Newton's scale predates Fahrenheit (1724) and Celsius (1742) and influenced both. Fahrenheit reportedly studied Newton's work before developing his own scale. Newton's scale was never widely adopted, as mercury-based thermometers proved more practical.
Common Uses
The Newton scale has no modern applications. It appears in the history of science and in physics education when discussing the development of thermometry. Some physics problems and unit conversion exercises include Newton-scale conversions as an academic exercise.
Did You Know? Facts About Newton
- Newton published his temperature scale anonymously in 1701 - his authorship was only confirmed later.
- Newton chose 12°N for body temperature and 33°N for boiling water, apparently preferring numbers with many divisors.
- The Newton scale should not be confused with the newton (N), the SI unit of force, also named after Isaac Newton.
- Newton used linseed oil rather than mercury because it has a larger thermal expansion coefficient, making temperature changes more visible.
- Newton's temperature scale predates both Fahrenheit (1724) and Celsius (1742), making it one of the earliest quantitative temperature scales.