# Lowthian Green՚s Tetrahedron Hypothesis on Origin of Continents and Oceans YouTube Lecture Handouts

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• Theory is based on geometrical principles
• Elie de Beaumont – first attempted this - pentagonal dodecahedral hypothesis with 12 faces
• Lowthian gave the hypothesis in 1875 – tetrahedral hypothesis
• His concept was supported by Fairbrain.
• Later ₹ Morgan & SW Woolridge worked on Lowthian Principles

Platonic solid is a regular, convex polyhedron constructed by congruent (identical in shape and size) regular (all angles equal and all sides equal) polygonal faces having same number of faces meeting at each vertex.

• Tetrahedron: Solid body having four equal plane surfaces, each of which is an equilateral triangle
• According to theory, process of cooling, to take the form of a tetrahedron or triangular pyramid, with four faces and four corners or coigns.
• Depressions and faces of the pyramid would be sea while coigns (corners) would reach out along the edges to form continents.
• In late 19th & 20th century superseded by continental drift and plate tectonics.

## Hypothesis Propounded

• A sphere is that body which contains the largest volume with respect to its surface area
• A tetrahedron is that body which contains the least volume with respect to its surface area

## Criticism

• Corners would sink to form a stable shape. Small globe can but enormous earth cannot.
• Again, continents are made of light SIAL and oceans made of SIMA (heavier) . Contraction could not account for distribution of continents without considering SIMA and SIAL.
• Balance of the earth in the form of a tetrahedron while rotating on an apex cannot be maintained.
• Earth rotates rapidly on its axis & spherical earth cannot be converted into a tetrahedron while contracting on cooling.
• Hypothesis of permanency of continents and ocean basins has been rejected by plate tectonic that validated continental drift concept.

Manishika