For more than one hundred years, the Ball watch company has maintained a strong reputation for manufacturing high quality timing instruments for demanding professionals. Equipped with high quality Swiss made movements, often with in house innovations, they are designed to be functional, practical and stylish.

One function which is rarely seen on a mechanical watch is a thermometer, and in a tribute to the scientist who first established the Absolute Thermometric Scale, Lord Kelvin, Ball have created the Trainmaster Kelvin, complete with functional and irresistible temperature gauge on its dial. 

In a limited edition of only 600 examples worldwide, this marvellous novelty is presented in a case of 18Kt rose gold, and with its domed sapphire crystal and clean rounded profile the Trainmaster Kelvin, at 39.5mm, is an elegant and reserved piece. 

Beneath the crystal, the sunburst effect on the silvered dial constantly plays with the light. A round porthole at the 1 o’clock position might seem like an unusual place for the date, but it’s generously sized and effective. Gently tapering applied gold hour markers complement the hands, and for optimal low light readability both have been accented with Ball’s signature tritium gas filled micro tubes which glow clearly in the dark.

Giving his name to the unit of measurement for his invention, the Kelvin (K) is commonly used in the fields of science today, but not so much in day to day life, and so dominating the lower half of the dial the temperature display is marked in centigrade (or Fahrenheit in the US). For reference and conversion Kelvin’s scale is etched into the sapphire glass caseback. Faced with the challenge of showing temperature within a wristwatch, the watchmakers used a fine bimetallic coil of steel and brass. Forged together, each metal expands and contracts differently, bending the strip back or forth as it heats or cools, and it’s this variance which ultimately moves the thermometer pointer.

To the rear, the etched sapphire glass reveals the ever reliable ETA 2892 automatic Swiss movement which beats within, and which has been certified a COSC chronometer ensuring exacting accuracy. The spinning of the gold inscribed rotor maintains the 42 hour power reserve.

The Ball Trainmaster Kelvin is presented on a crocodile leather strap with 18kt gold pin buckle.