On the Writings of the Insane is a peculiar inquiry into the mind of hospitalized and medicated patients at the Cambridgeshire County Asylum. It was written by the Medical Superintendent G. Mackenzie and published in 1870. The book seeks to decipher the patients handwritten notes and drawings, and contrary to what one might believe he does so very respectfully. On the Writings of the Insane is illustrated with the patients drawings and notes.