Before it became known for its television commercials, Coca-Cola promoted itself through diverse methods of advertising—from porcelain signs and tin drink trays to wall clocks and even toy trains. Thermometers were just one item in this larger strategy of “practical” advertising that included chalkboards, light fixtures, and “push” and “pull” door signs, all of which were designed to position the Coca-Cola brand in prominent spots throughout cafes and stores. Because these items were both promotional and utilitarian, they would stay on display long after posters and other ephemeral forms of advertising had been discarded.
Coca-Cola began making and distributing thermometers in the 1920s—a few date to even earlier than that. Most retailers displayed them outside, so the early thermometers were often made of metal, which were tinned for durability; others were made of wood. They ranged in size from relatively small (nine inches tall) to fairly large (so-called cigar-shaped versions were about 30 inches in height), though a fairly common size was about 16 or 17 inches.
Frequently, these three-dimensional thermometers were shaped like bottles of Coke, whose so-called “hobbleskirt” or “Mae West” shape was standardized in 1915. Throughout the 1920s, as glass bottles in general became popular with retailers and customers alike, Coca-Cola promoted its now-familiar bulge-in-the-middle bottle design via its thermometers, which incorporated a vertical temperature scale below the Coca-Cola logo.
As the years went by, the look of Coca-Cola thermometers evolved to stay in step with trends in the popular culture. For example, many Coca-Cola thermometers from the 1940s featured an oval-shaped Art Deco design to match the interiors of drug stores and soda fountains of the day. Many of these were made out of Masonite; some were painted gold.
Other metal thermometers were constructed like porcelain signs, and some of these are quite prized by collectors today. One design, for example, featured a circular red top, outlined in yellow, with a similar circle shape at the bottom, within which was a green Coca-Cola “Silhouette Girl” against a yellow background. In most of these, the thermometer itself was positioned between these two circles, at center-left, against a field of red and adjacent to the words “Thirst knows no season.” In rare examples, this center section is rendered in “Silhouette Girl” green.
In the 1950s, Coke’s classic red-button sign became more widespread, so the shape was repurposed for thermometers. Unlike vertical bottle-shaped thermometers, these devices were circular, with a hand like a clock’s to indicate the temperature. Most red-button thermometers measured about a foot in diameter and had glass fronts, but by the 1960s, many of these and other Coke thermometers had made the transition to plastic.
Regardless of the period or specific design, all Coca-Cola thermometers sported the brand’s instantly recognizable red-and-white color scheme and featured popular slogans. In addition to “Thirst knows no season,” famous slogans included “Delicious and Refreshing” and, of course, “Things Go Better with Coke.”