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The compressorium (plural: compressoria) is a scientific apparatus for applying pressure to a sample for examination with a microscope.
Widely used by microscopists in the 19th century,[1][2][3] they were produced by companies such as Bausch and Lomb.[4]
Many versions of compressoria were developed over the years, with one of the first attributed to the famous histologist Jan Evangelista Purkyně,[5] see picture.
Compressoria were still used in the twenty-first century for the identification of Trichinella worms in samples.[6]