He was born in Islington, London. He claimed to materialize spirits in his séances. It was discovered that the materializations were fakes. The levitations of Eglinton were also revealed as tricks.
In 1876 Eglinton was exposed as a fraud when the psychical researcher Thomas Colley seized the "spirit" materialization and cut off a portion of its cloak. It was discovered that the cut piece matched a cloth found in Eglinton's suitcase. Colley also pulled the beard off the materialization and it was revealed to be a fake, the same as another one found in the suitcase of Eglinton.
In 1886 the spiritualist John Stephen Farmer wrote a biography of Eglinton.
Eglinton performed slate writing mediumship and his leading critics were the psychical researchers Eleanor Sidgwick and Richard Hodgson. In 1886 and 1887 a series of publications by S. J. Davey, Hodgson and Sidgwick in the Journal of the Society for Psychical Research exposed the slate writing tricks of Eglinton.
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Edward Clodd. (1917). The Question: A Brief History and Examination of Modern Spiritualism. Grant Richards, London. pp. 50–106