Bonnet ornament

A hood/bonnet ornament, radiator cap, motor mascot or car mascot is a specially crafted model which symbolizes a car company like a badge, located on the front center portion of the hood. It has been used as an adornment nearly since the inception of automobiles.

According to the author of A History of Cars written for youth, the first "hood ornament" was a sun-crested falcon (to bring good luck) mounted on Egyptian pharaoh Tutankhamun's chariot.

In the early years, automobiles had their radiator caps outside of the hood and on top of the grille which also served as an indicator of the temperature of the engine's coolant fluid. The Boyce MotoMeter Company was issued a patent in 1912 for a radiator cap that incorporated a thermometer that was visible to the driver with a sensor that measured the heat of the water vapor, rather than the water itself. This became a useful gauge for the driver because many early engines did not have water pumps, but a circulation system based on the "thermo-syphon" principle as in the Ford Model T.

The "exposed radiator cap became a focal point for automobile personalization."

Hood ornaments were popular in the 1920s, 1930s, 1940s, and 1950s, with many automakers fitting them to their vehicles. Moreover, a healthy business was created in the supply of accessory mascots available to anyone who wanted to add a hood ornament or car mascot to their automobile. Most companies like Desmo and Smith's are now out of business with only Louis Lejeune Ltd. in England surviving. Sculptors such as Bazin, Paillet, Sykes, Renevey, and Lejeune all created finely detailed sculptures in miniature.

Restrictions to the fitting of ornaments on the front of vehicles have been introduced in some jurisdictions. Projecting decorative designs on the hood may increase the risk of injury to pedestrians in the case of an accident.

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Wikipedia