Hebdomas 8 days early 1900s

Switzerland 1910-20, brand Hebdomas, material metal, cm 5x6,8x1,5

Pocket watch, vintage, with original chain and with exposed balance wheel and decorated dial, a small masterpiece from another time.
Brand:Hebdomas
Hebdomas in Greek and Latin refers to the Holy Week. These watches promise to run for at least a week without being rewound (originally it was wound once a week when people went to the market in town).
Even a little more, since the dial usually says 8 Jours, 8 Days or 8 Tage.
In this watch, the name Hebdomas is present, so it is after 1907 but according to some, that little button on the case next to the crown disappears after 1917.
If it were true, looking at the back, we could date this watch between 1915 and 1917.

The inventor of the Hebdomas is considered to be Irénée Aubry from Saignelégier in Switzerland, who received Swiss patent number CH88 for a first version of these watches in January 1889.
A few months later, Aubry transferred the patent to the company Aubry, Graizely & Godat, which then began to produce the Hebdomas pocket watches. Graizely further developed Aubry’s concept by patenting the familiar shape of the large balance bridge in Swiss patent CH24675 in 1901.
The name Hebdomas was established for this version with the large balance bridge, but only around 1906.
Aubry retired from the business in 1912 and in 1913 Otto Schild took over Graizly & Co. He produced about 1,000 Hebdomas watches per day with Schild & Co in La Chaux-de-Fonds around 1918.
After the termination of Schild & Co, the rights to the design and brand Hebdomas passed in 1982 to the company Xantia, which produced these watches until the 1990s.

WA-01-0001 - available