The process known as antigen-antibody precipitation was invented in 1901.
The test was originally designed to figure out what species the sample belonged to. The test was a major break through in forensic science during the 20th century. It was further refined by a scientist named Maurice Muller
http://www.fmap.archives.gla.ac.uk/Case%20Files/Bloodtest/Bloodtest.htm
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Created with images by dxiri - "Human_Blood_Cells_by_fine_ass_tramps"