Takes a moment to write. Sends various brochures and observations on magnetic intensity in Germany. Asks JH to give a copy of it to [Charles] Babbage and [Henry] Kater. Congratulates JH on being named correspondent to the Institute of France. Lost his father-in-law. Has asked [James] South to press construction of AQ's instruments, but no luck. Requests JH visit Edward Troughton and the instruments.