Mechanical movements and chronometry

In 1952, Longines brought out its first self-winding calibre designed in house, the 19A. The factory was acquiring knowledge relating to automatic winding technology. In 1956, this experience was mobilised for the design of a small oval self-winding movement which was intended for ladies’ watches, the 14.17. Dependent upon the decisive progress made with regard to lubrication, this calibre was fitted with a balance and spring assembly oscillating at a frequency of 19,800 vibrations per hour; it constituted the only self-winding movement for ladies’ watches developed by Longines. The increase in the frequency of oscillation of its regulating organ marked a basic trend in the development of the mechanical movement, particularly in the context of the emergence of technological competition based on electronics and quartz. This progression, rendered possible by the independent development of the components, also had an impact on chronometry. In 1959, Longines developed a calibre specifically designed for observatory competitions. Designated by reference number 360, this movement, rectangular in shape with rounded corners, was produced in a very small series. It was exclusively allocated to the precision competitions in which the major watchmaking companies so eagerly participated. The construction characteristics of the 360 reflected its function: although its total surface area was very close to the limits specified by the observatories, the large size of this calibre permitted the use of a large barrel mainspring and promoted good management of the distribution of energy. In addition, the dimensions of the 360 made it possible to use a large balance and spring assembly oscillating at a frequency of 36,000 vibrations per hour, enabling a very precise rate. The 360 calibre set new records for precision in the wrist chronometer category at the Neuchâtel Observatory.

In 1957, Longines presented a timepiece which was named the "Flagship". Fitted with a 30L calibre built by the technicians of the manufacture in 1955, this watch set the seal on the adoption of a new concept for marketing watches. Although the technical characteristics remained an essential parameter of production, the fact of giving a timepiece a name opened up a strategic field which had until then been little exploited. Longines used the production of this watch as a centre around which it planned all of its publicity in the context of a world wide advertising campaign.

At the end of the 1950s, Longines devoted significant resources to perfecting its mechanical movements. Calibres which were specially designed for wristwatches seemed at that time to have strong potential for advancement. Increasing the frequency of oscillation of the regulating organ formed at that time a technical trajectory which was systematically pursued. However, by contrast with earlier practices, the design of calibres was undertaken simultaneously with the creation of watch models. At the Basel Fair in 1959, Longines presented a timepiece which it christened "Jamboree"; it was fitted with a calibre – available in several variants – also designed in 1959, the 280. In the same year, the Saint-Imier brand also brought out a new 11 ½-line self-winding calibre, the 290, which made the production of an automatic Conquest range possible. Following the example of contemporary movements, the 290 and its derivatives had a regulating organ oscillating at 19,800 vibrations per hour. In 1960, Longines developed the 340 calibre and its variants (341, 342, 343, 345) with which the Flagship timepieces are fitted. This 12-line self-winding movement is also fitted with a balance-balance spring unit which vibrates at a frequency of 19,800 vibrations per hour.

Within the factory, working methodology was being rationalised according to the principles of the scientific organisation of work. In the area of research and development, the second half of the 20th century saw the establishment of new rationales in the process of technical creation. At the Longines factory, engineering science was increasingly replacing the watchmakers’ technical expertise which had reigned supreme up to that time. The company called upon specialised skills to deepen its knowledge in certain fields which were being explored at that time, such as electronics and chemistry. Thus new technologies for the measurement of time, specifically electronics and quartz, were juxtaposed with traditional watchmaking techniques. This technical dichotomy of activity necessitated recourse to new expertise from outside the watchmaking industry.