Medical History: How Accurate Were Thermometers 100 Years Ago?

We are curious to know how thermometers worked back in the day. Did they give the desired results? Did they help to make people feel better? Read this article to find out how accurate thermometers were 100 years ago, and a brief history about these important scientific instruments.

What is a Thermometer?

A thermometer refers to an instrument that helps in measuring temperature. It can measure the temperature of different solids like food, liquids like water, and gas like the air we breathe. The three well-known measurements of temperature are Kelvin, Celsius, and Fahrenheit.

Weather Records from 100 Years Ago

Reports of the weather that were taken 100 years ago were quite accurate. Some might even say they were a tad bit more accurate than those taken today. Weather Bureau thermometers made in the early 90s were quite accurate to 0.1 degree and dew point temperatures were calculated by hand making use of wet-bulb readings that were ventilated. 

This day, electronic temperature sensors are quite accurate, having a little tolerance of plus or minus two degrees and an automated dew point which is given tolerance of minus or plus four degrees. Measuring precipitation using 8-inch rain gauges with accurate techniques, while these days the thermometers employ less reliable tipping bucket rain gauge which could give off faulty readings.

Thermometers from a 100 Years Ago vs. Thermometers of Today

A basic clinical trial was done to compare and investigate the use of mercury thermometers used from 100 years ago and that of the digital thermometers used now. Both clinical and laboratory studies show that there isn’t a significant difference in the average accuracy of both types of thermometers. But when one looks at their readings, we consider both mercury and electronic thermometers. In this clinical study, between 9 to 23% of repeated measurements using a thermometer that works with electricity, which differs by 0.5 degrees C or more while the range that corresponds with mercury thermometers is 0.6%.

This also shows that when one makes clinical measurements using mercury thermometers you wouldn’t enjoy the clinical advantage that you’ll get if you made use of the digital thermometer instead.

Letter from a 100 Years ago on the Accuracy of Thermometers

Why does the sky have a blue color and not green, red, purple, or yellow? The white light that we as humans perceive as sunlight, which is also known as electromagnetic radiation, has various wavelengths and colors that all blend. Each color has its very own wavelength. The color blue has the shortest wavelength, and it bypasses all other colors, which is why whenever we look at the sky, blue is all we see. The mercury thermometers used back then were accurate enough to be able to tell the wavelengths of these colors better.

This doesn’t mean we should forever abandon the mercury thermometers. We can choose to make use of them if need persists. However, electronic thermometers are safer.

Medical History: How Accurate Were Thermometers 100 Years Ago?
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