Sveinn was the first person to propose the theory that glaciers move under their own weight, like viscous material. He focused on glacial sediments, melt-water rivers and floods, and the effects of subglacial volcanos. His conclusions made significant findings in regards to the formation and dynamics of glaciers. His treatise Draft of a Physical, Geographical, and Historical Description of Icelandic Ice Mountains on the Basis of a Journey to the Most Prominent of Them in 1792–1794 was submitted to the Naturhistorieselskabet in Denmark in 1795, where it languished for almost a century. Not until the 1880s was the Danish manuscript published in part in Oslo, Norway; in 1945 it was published in its entirety in Icelandic by glaciologist Jón Eyþórsson. Due to its isolated location, Iceland remained a remote location for geological investigation until the 20th century.
