After 1896 his main scientific interest switched to oceanography; in the course of his research he made many scientific cruises, mainly in the North Atlantic, and contributed to the development of modern oceanographic equipment.
Setelah tahun 1896, peminatan saintifik utamanya beralih ke oseanografi; dalam rangka risetnya, ia membuat beberapa penjajap saintifik, utamanya di Atlantik Utara, dan berjasa atas pengembangan peralatan oseanografi modern.