93-5 From Water Buckets to Horizontal Pendulums: The British Raj, Colonial Seismology, and the Discovery of the Interior Structure of the Earth

Session: Crossing Borders in the History and Philosophy of the Geosciences

Presenting Author:

Author:

Abstract:

During the late 19th and early 20th centuries, the British were leaders in the newly emerging discipline of modern seismology. But why? They had relatively few earthquakes in their own islands, and the earthquakes they did have tended to be minor. This paper argues that the colonial occupation of South Asia and the earthquakes that occurred there around the turn of the century were major factors in Britain's status as a leader in early seismology. Colonial geologists, and others in their scientific communities, were wrestling with questions about how earthquakes should be studied, what counted as permissible evidence and sound method, what did (and did not) cause earthquakes, how to read instruments (from a dedicated seismograph to a bucket of water), who was 'able' to observe earthquakes accurately, and how international evidence could be used to understand the internal structure of the earth. At every level, colonialism and 19th century race science were central to the issues, questions, and answers. Colonialism influenced how white geologists collected, corrected, and presented seismological evidence. It also prompted them to increasingly rely on technology rather than human report, even though the instruments were in their infancy and they had not quite developed a standard for how to read seismograms. Geologists petitioned for several more seismograph installations and international organizations that would collect the evidence. These measures enabled scientists to develop a more complete picture of earthquake physics. One product of these efforts was the discovery of the Earth's outer core, and, just as importantly, the discovery that the globe's interior was made of discernible layers, an important break from earlier concepts of the Earth's structure.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-6679

© Copyright 2025 The Geological Society of America (GSA), all rights reserved.