What Is a Glass Tube Thermometer, Anyway?
As part of our 80th anniversary celebration, we’re continuing to dive into the past and share insight into the beginnings of Chaney Instrument Co. and the AcuRite brand. This month, we’ll briefly revisit how the company got its start 80 years ago and discuss the product that got Chaney on its feet: the glass tube thermometer!
Capable of measuring the temperature indoors or outdoors, the original Chaney Instrument Co. glass tube thermometer was a sealed glass tube with liquid inside. When heated, the internal liquid expanded. When cooled, the liquid contracted. The glass tube itself was mounted on a calibrated scale that provided measurement readings, read by matching the top of the internal liquid with the corresponding measurement on the scale.
The liquid inside early glass tube thermometers was Mercury, but when word got out about its poisonous nature, manufacturers replaced it with red-tinted kerosene or coal oil. These safer alternatives were also easier to see than the reflective silver of Mercury, making for a more user-friendly and kitchen-safe thermometer. Current-day glass tube thermometers mainly have dyed-red alcohol as their internal liquid.
Chaney’s Glassworks Education and Creation of Automated Glass Tube Sealing
John L. Chaney, as outlined in last month’s blog, was a hands-on man — especially when it came to tinkering with glassware. He gained most of his talent from working for a glassworks company in New York in the mid-1930s (prior to working in Springfield, Ohio). There, he learned glass forming and how to properly cool glass to maintain its integrity and safety, which is especially important during large temperature swings.
Following his creation and sale of an automated glass-sealing method in Ohio, he hired his brothers, his sister, and other women in Lake Geneva, Wisconsin, to create glass components that assisted American forces in World War II. Chaney-made glassware was in U.S. tanks, aircraft, and ships — helping the U.S. forces fight on land, air, and sea! More wartime-effort information to come later this year!
Chaney Glass Tube Thermometer History and Uses
Following the war’s conclusion in 1945, Chaney and his team turned their focus to what they knew best: glass tube thermometers. Back then, American households, if they had one, could only rely on their Galileo thermometer if they wanted an estimation of their in-home temperature. They obviously couldn’t rely on a digital thermometer, as they of course didn’t exist yet! And as for outdoor temperature, no easily accessible outdoor thermometer was available.
Most early glass tube thermometers by Chaney Instrument Co. were made to improve everyday-use kitchen products. For example, Chaney held one of the first patents for the turkey baster, a product he sold along with a “roast meat thermometer” and the “deep frying candy and jelly thermometer.” The set, which was marketed as the perfect wedding, housewarming, and Christmas gift, included the two different-sized glass tube thermometers, both with appropriate scales and food-specific temperature guides. A meat skewer and a small recipe booklet were also included!
To get accurate measurements of roasts, candy, or other deep-fried foodstuffs (families deep fried a lot more often back then!), the thermometer would be inserted into the roast or dipped into the frying oil and clipped onto the side of the pot. The heat from the food or oil would expand the internal liquid and provide the temperature measurement according to the affixed scale. Just a little different than the stainless steel digital temperature probes that are available today!
In the 1970s, the microwave oven was pitched to American households as a replacement for the conventional oven. And with the rise of this new countertop oven, people needed a way to know the internal temperature, so Chaney Instrument Co. began creating special glass tube thermometers for microwave use. Customers could even mail their proof of purchase to AcuRite headquarters in Lake Geneva for a limited-edition AcuRite microwave cookbook!
Of course, households also used AcuRite glass tube thermometers to get indoor and outdoor temperature readings. They could be easily mounted on walls in the house, garage, or shed. They fit nicely in refrigerators, freezers, and wine cellars. They could also easily be mounted outside a window, like above the kitchen sink, to let people inside know what the temperature was outside.
These glass tube instruments, now considered antique and vintage thermometers, were largely replaced in households by rounded coil thermometers in the 1980s. With its rotating indicator, the dial-style thermometer can be much easier to read from a distance than a small glass tube thermometer’s reading. As with many instruments, technology advanced and ousted the glass tube thermometer from popularity.
Many Thanks to the Glass Tube Thermometer
Chaney Instrument Co. and AcuRite have much appreciation for the glass tube thermometer and its popularity in the company’s early years. It paved the way for future AcuRite products like the digital thermometers seen on many of our weather stations, clocks, and stand-alone thermometers — some of the most accurate thermometers available! We salute the glass tube thermometer, especially the world’s largest (more to come on that later this year!), and look forward to bringing our great customers more reliable thermometers in the years to come.
Do you remember any of these vintage AcuRite glass tube thermometers? What about the cooking set? Did your family have any of these kitchen gadgets growing up? We’d love to hear from you in the comments below!