Copy of draft letter, from Sir John Herschel to Augustus De Morgan, dated at Collingwood Copy of draft letter, copied as part of the correspondence project led by Colonel John Herschel FRS following the death of his father. Returns H. P. Brougham's (Baron Brougham and Vaux) paper. Does not recall any similar theories, but does not think his own theories are shaken by those of Brougham. Finds that Augustus De Morgan has already done extensive work on the calendar. 18 February 1849