Ørsted describes how the distribution of plant and animal life is governed by the penetration of light at different depths, the nature of the seabed and the physical properties of the water. By linking biological observations to hydrography and geology, he lays the foundation for a completely new way of understanding the sea as a coherent ecological system. 

This new edition contains a complete translation into English and a facsimile of the original, making Ørsted’s pioneering work accessible and relevant to today’s readers. Being a unique historical document from the end of the Little Ice Age (1300–ca. 1900), before large-scale human influence changed the ecology of the oceans, the book is an invaluable resource for ecologists, marine biologists, environmental historians and anyone seeking a deeper understanding of the natural state of the sea.