Lieutenant Henry Crookshank (c. 1891-1972) was born in Dublin the son of Robert Crookshank (d. 1929) SC and his wife Elizabeth née Stokes (d. circa 1943). Elizabeth Stokes, the eldest of eight children, was of the family which included bacteriologist Adrian Stokes and archaeologist Margaret McNair Stokes.
Henry Crookshank, the second eldest child and the second son, entered Trinity College in 1913 to read mathematics. He joined the Dublin Fusiliers, in 1914, with his brother Arthur who died in Gallipoli. Lieutenant Crookshank was mostly stationed in the Middle East; he went to France in 1918.
After his service Crookshank returned to TCD in 1918 to the engineering school; in 1929 he joined the Geological Survey of India. In 1921 he married Eileen Mary Lodge, in Kolcata Cathedral. They had three daughters, one of whom, Anne (b. 1927), was the Professor of the History of Art in TCD.
In 1929 Crookshank joined the Geological Survey of India; he became the superintending geologist and worked on oil indications at Drigh Road, near Karachi. He worked on sapphirine in the Vizagapatnam District, Jabalpur plains from Satpura Gondwana Basin, and on the geology of the northern slopes of the Satpuras between Moraud and Sher rivers. He was a fellow of the Indian National Science Academy.
The Crookshank letters in this project were acquired by the Library in 2007 and are the only Crookshank-related material in the collection.