Potters have been digging and processing their own clay for millennia. It has only been since the Industrial Revolution, which began in the 1800s, .
A Biography of Henry Clay, by Daniel Mallory—A Project Gutenberg eBook.
Cultural Patterns of Soil Cultivation in Europe 1: Polytheistic Context
The Project Gutenberg eBook of Walden, by Henry David Thoreau
Indurated soil nodules: A vestige of ancient agricultural practices? - Giosa - 2022 - Geoarchaeology - Wiley Online Library
Plough - Wikipedia
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23 Things to do in Waco Texas - Jim Parlee - We Bridge the Gap Between Buyers and Sellers
Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray.
When did humans first start to make things with clay? - Quora
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