In 1874 Auguste Denayrouze established a new company which was formed through the merger of two previous companies in which he held partnerships. The two old companies included Rouquayrol-Denayrouze (established in 1865 and both men were partners) and the other was a sponge diving company that Auguste and his brother (Louis Denayrouze) were directors of. The newly amalgamated company of 1874 was called ‘Specialites Mecaniques Reunis‘. A year later in 1875 Benoit Rouquayrol died, followed in 1883 by Auguste Denayrouze. The remaining partner, Louis Denayrouze remained in charge of the company until it was taken over three years later in 1885 by Charles Petit.

Charles Petit’s new air-pump, the ‘Modele 1888 a joints Giffard’ Photographs David L.Dekker

1874. The ‘Specialites Mecaniques Reunis’ company is established

In 1885 Charles Petit bought the ‘Specialites Mecaniques Reunis’ company. The company name remained the same until 1895 when it was changed to ‘Societe Charles Petit’. Three years after Petit bought the company he introduced a new air-pump: the ‘Modell 1888 a joints Giffard’. The new air-pump was redesigned and now had its cylinders fixed at the base plate and included moving pistons (the two earlier models had fixed pistons and moving cylinders). The ‘reservoir intermediair’ (the tank which was placed between the pump and the air-hose in the previous model air-pump) was now integrated into the base and central column of the pump. The gauge was also fixed to the central column.

1885 Charles Petit buys ‘Specialites Mecaniques Reunis’

1880. ‘Specialites Mecaniques Reunis’ continues production of the 12 bolt helmets previously manufactured by their competitor ‘Cabirol’

Cabirol appears not have exported any diving apparatus to the Netherlands, probably because his apparatus was very similar to that of Augustus Siebe from England. After Cabirol died in 1874 his company was taken over by his nephew Charles Ferrus. What became of Charles Ferrus is not known but his company disappeared from its working address in 1880. During this period the ‘Specialites Mecaniques Reunis’ introduced their 12-bolt helmets and diving dress. It is possible that ‘Specialites Mecaniques Reunis‘ bought the remaining stock of the Cabirol / Ferrus company in 1880. This is supported by the fact that there are air-pumps known to exist which are built with Cabirol parts but have been given the company badge of the ‘Specialites Mecaniques Reunis‘, or that of Charles Petit.

A fine Cabirol helmet with various markings: Cabirol often stamped the breastplate of his helmets with the information about the prizes that he won at the 1855 World Exhibition in Paris. However, his nephew Ferrus soldered a badge over the text after he took over his uncles business in 1874. This helmet is from the collection of Leon Lyons, St. Augustine Florida. Photographs, David L.Dekker

1880 the first 12-bolt helmet made by ‘Specialites Mecaniques Reunis’

Above: one of the first 12-bolt helmets made by ‘Denayrouze’ (by then the company name had changed to ‘Specialites Mecaniques Reunis’). The helmet has lost its badge therefore it could have been made after 1885 when Charles Petit bought the company. Two later versions of this helmet would be used in production which were slightly larger and smaller in size and volume, but otherwise looked the same as the previous helmet. Helmet above from a private collection; photographs, David L.Dekker