A comprehensive understanding of how marine science materialized should include studies on the development of theories, scientific practice and instrumentation. This paper argues that Scandinavian scientists came in forefront around 1900, due to the breakthrough of the theory of dynamic oceanography, but also owing to the emphasis put on fieldwork partly under extreme conditions, technical skills and a joint Scandinavian effort to define international standards for instrumentation and measurements. The case study covers Pettersson’s insulated waterbottle (ca. 1890); the Pettersson-Nansen bottle (ca. 1900) and The Nansen-Ekman bottle (ca. 1905), the last one became a standard instrument for sampling sea water until 1980.

Precise measurements of the salinity and temperature at specific depth are crucial to obtain accurate oceanographic data. Around 1890 numerous watersamplers were in use, but no common standard for samplings and measurements was established. The Swedish chemist and scientific entrepreneur Otto Pettersson (1848–1941) and the Norwegian zoologist, explorer and oceanographer Fridtjof Nansen (1861–1930) belonged to a group of Scandinavian, marine scientists fervently working to have their instruments and salinity methods set as international standard. The International Council for the Exploration of the Sea (ICES) (established in 1902) with its regular and coordinated surveys, became their principal channel of influence.

The paper examines the strong efforts by which Scandinavian scientific theories, methods and technology were spread to the United Kingdom, Germany, Canada and the USA – but not to France. Despite France’s renowned universities, advanced marine stations and its link to Monaco, a hotbed of oceanographic studies owing to the abundant patronage of Prince Albert I of Monaco (1848–1922), the country made few contributions to oceanography until the 1960s. One motive for the disinterest may have been national pride; another explanation is Julien Thoulet (1843–1936), a dominant oceanographer in this period. He dissuaded the dynamic oceanography, considering complex mathematical modelling and interpretation as a fruitless way to understand the ocean conditions. Thoulet also rejected the watersamplers developed by the Scandinavians and constructed his own. Despite a substantial marine scientific community and the national efforts France did not succeed in developing a distinctively improved, different scientific concept of the ocean.