Dive Into Time: A Look at Panerai's Naval History

This holiday season I received a pretty spectacular gift – a piece of military history. You see, I’ve always admired Panerai’s hertiage mainly because of the family ownership (much like my history with Shreve & Co). It wasn’t until I got to experience the Luminor first hand and learn of its military heritage that I knew it was a must-have for my watch collection. The Luminor along with its predecessor the Radiomir, was a top military secret up until the 1990’s and accompanied Italian Navy frogmen on their underwater missions during World War II. The two models were and still are the first true diver’s watches known to the industry.

Watchmaker Giovanni Panerai opened the company’s first workshop in Ponte alle Grazie, just outside of his hometown of Florence, Italy, in 1860. Not much is known about Giovanni – except for his relationships with prestigious watch makers, like Rolex, who provided movements for his timepieces and clocks. Giovanni’s connections became vital in creating a name for the Panerai brand. In fact, the company was contracted to develop ship clocks for the Regia Marina (the Royal Italian Navy) throughout the 19th century.

In 1900, under the leadership of Giovanni’s grandson, Guido, the company became the official supplier of clocks and precision instruments to the Royal Italian Navy. With the Navy’s increasing need for visibility underwater, Panerai went to work developing prototypes designed for frogman, commandos and divers. In 1916, the company developed a radium-based powder that when submerged into darkness became luminous. The substance’s high visibility made it a key element in Panerai’s high precision instruments – timers for detonators, underwater wrist depth gauges, wrist compasses and torches.

However, It wasn’t until the eve of World War II that Panerai created the wrist worn timepiece prototype called the “Radiomir”. Designed specifically for the First Submarine Group Command, the Radiomir featured a large cushion-shaped steel case, luminescent numerals and indices, wire lugs welded to the case, a hand-wound mechanical movement, and a water-resistant strap long enough to be worn over a diving suit. In 1936, only 10 prototypes of the Panerai Radiomir watch were distributed among frogmen commandos, giving the Navy a huge advantage over their advisories.

Panerai continued to perfect the Radiomir model over the next two years until it went into production in 1938. The company made a number of changes at the request of the Navy and began producing a new model that featured a sandwich dial, made from overlapping plates that allowed the upper part to have perforated indices and numerals making the radium paint underneath more legible and luminescent than if the numerals were simply printed or painted onto the dial.

The Radiomir watch served mainly as a navigational instrument in World War II. A diver could use the watch to measure the time it would take him to swim to a target by covering a partial stretch of the course for a predetermined length of time. Unlike most watches at the time, the Radiomir’s sandwich dial only had markings at five-minute intervals rather at every minute. The technique used to cut through the top layer of the sandwich dial, which is still employed today, could not be used to create 60 luminous indexes without jeopardizing the dial’s durability which was all the more reason that the Radiomir was made for longer missions.

In 1941, Italian Navy divers perpetuated what was the Raid on Alexandria. Straddling torpedoes like underwater motorcycles, six frogmen put British battleships as well as a nearby Norwegian tanker out of commission and almost changed the course of the war. The divers steered their explosive cargo to established targets and detached mines from the front of their torpedoes and attached them to the hull of their opponents’ battleships. Timing was a matter of life and death, and the frogmen relied on the Radiomir for precision.

By 1949, the toxic effects of radium were better documented and the Radiomir was replaced by the Luminor model which featured a new self-luminous substance that used less radioactive material than its predecessor. The new model also featured a crown-protecting bridge with reinforced wire lugs created from the same block of steel as the case.

It’s important to note that the Radiomir and the Luminor were sold only to the military. Throughout the 1930’s and 40’s, collectors who wanted a Panerai watch had to find one at an auction. For the next 44 years Panerai continued to make watches and other instruments exclusively for military use, and in 1993 produced its first collection of limited edition timepieces, based on the historic military models, for the general public.

The two Panerai watches, named in honor of the luminescent materials that made them glow in the dark, are still the only two models the brand produces today, (except for the occasional re-edition of the Mare Nostrum, L’Egiziano and some collectors’ pocket watches).

The headquarters of the company are still in Italy, but production is now in Switzerland in a state-of-the-art manufacture just outside Neuchâtel. The first in-house movement appeared in 2005 and, to date, 21 proprietary movements with increasing complications have been developed by the company. Today, watches are often sold out before they reach our shelves and for the last two decades Panerai has stayed on course, true to the iconic design of its historic models – the Radiomir and the Luminor.

Wearing my Panerai Luminor in our new store in San Francisco often reminds me of the watch’s history, the history of watchmaking as a whole and my family’s journey to carrying the world’s finest timepieces. There is meaning in every piece we carry, whether it’s the world’s or your own.

Want to learn more my Panerai Luminor?

Feel free to come into a Shreve & Co store and explore every one of Panerai’s historic models. I’m happy to discuss the history of each model and it’s pros and cons in our San Francisco store but all of our staff is well versed in subject. We carry Panerai at both our San Francisco and Palo Alto locations and you can schedule an appointment here.

A special thank you to Panerai for the photographs in this post.