As with the Indian volumes there were problems in locating papers and there was a particular problem with the year from December 1809 for which the Duke's papers had been lost in a shipwreck in the Tagus. Gurwood made strenuous and prolonged efforts to obtain papers from a wide range of the Duke's correspondents writing, often several times, to individuals or their descendants. He made a number of searches in official collections including the Inspector General's office at the Ordnance and the Commander in Chief's Office, and he wrote to Lisbon to ask for a search for the Duke's letters to Admiral Berkeley which were believed to be in the Portuguese War Office.
