Artificial hydraulic lime from calcined limestone and clay (Vicat)
Cal hidráulica artificial por calcinación de caliza y arcilla (Vicat)
- Date
- 1817-1818 · confidence high
- Place
- Souillac, Lot, France
- Credited to
- Louis Vicat
- Field
- Tools
What was discovered
While building the Souillac bridge, Vicat found that calcining limestone with clay in controlled proportions yields a lime that sets under water. He published the proportions and tests, laying the chemical basis of modern cements.
Vicat published his Recherches expérimentales sur les chaux de construction in 1818; Smeaton had already observed natural hydraulic lime in 1756 and James Frost patented 'British cement' in 1822.
What it led to
- industrial cement manufacture with controlled composition
- standardised strength and setting tests
- Aspdin's and Johnson's Portland cement