Cal. 835 was the first mass-produced automatic movement from Eterna. Introduced in 1939, it was based on the compact hand-winding Cal. 845 and similar Cal. 905. The new family measured 11.75 to 13 ligne with the bumper winding rotor installed and pioneered features like a slip spring in the barrel to avoid over-winding. It was mass produced in the 1940s, giving Eterna a lead in waterproof watches.
The Cal. 835 family was not part of the Eterna-Matic family, which appeared in 1948 as a line of compact automatic movements for ladies watches. This line introduced the trademark ball bearing full-rotation weight, which was adapted for the later larger Eterna automatic movements as well. These would replace Cal. 835 and adopt the Eterna-Matic name in the 1950s. The introduction of these movements spelled the end for the Cal. 835 family, which was quickly abandoned around 1950.
The initial movements in this family had small seconds, with center seconds added via indirect drive. Direct center seconds were added around 1945 in Cal. 1158 and 1159. But bumper automatic movements were clearly not the future and all were retired just a few years later.
Successor: Eterna-Matic 1200 Family
| Cal. 835 | 12.5”’ | Small seconds |
| Cal. 834 | 12.5”’ | Small seconds |
| Cal. 833 | 12.5”’ | Center seconds |
| Cal. 1033 | 9.5”’ | No seconds |
| Cal. 1034 | 9.5”’ | Center seconds |
| Cal. 1076 | 13”’ | Small seconds |
| Cal. 1077 | 13”’ | Center seconds |
| Cal. 1176 | 13”’ | Small seconds |
| Cal. 1158 | 12”’ | Direct center seconds |
| Cal. 1159 | 13”’ | Direct center seconds |
