Copy letter, from Sir John Herschel to Henry James, dated at Collingwood Copy of letter, copied as part of the correspondence project led by Colonel John Herschel FRS following the death of his father. Regrets delay in acknowledging his Notes on the Great Pyramid; it was due to a temporary loss of the work. Finds Henry James's theory on the inclination of the passages very practical. Comments on the accuracy of the pyramid builders. 30 September 1865