Because Hughlings Jackson directed that his personal documents be destroyed upon his death, none of his own clinical records are known. However, we have discovered several pages of notes in the Royal London Hospital Archive written in 1893 by Jackson to his House Physician at Queen Square concerning his proposals for investigation of a patient with external ophthalmoplegia. We have linked this document to JC, a patient described by Jackson in Neurological Fragments, in papers published in the Lancet between 1895 and 1909. We have followed Jackson's analysis of JC through the clinical records at the London Hospital and at Queen Square. These documents illuminate the clinical and academic background to Jackson's neurological practice in late nineteenth-century London.