Very interesting.

A couple of years ago I attended a lecture arranged by the Society of Genealogists in London. The speaker was an archivist from The national Archives in Kew who described some little known ministerial letter books with copies of letters from private citizens to the administration.

These are a largely untapped resource for local historians and I suspect the Irish Potato Famine 1845-1850 may be the subject of some of them

Unfortunately I am in Copenhagen and my notes are in Birmingham

http://www.nationalarchives.gov.uk/

http://www.catalogue.nationalarchives.gov.uk/default.asp

>> the Catalogue (formerly PROCAT)
the Catalogue contains 9.5 million descriptions of documents from central government, courts of law and other UK national bodies
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You ran a search on "letters" restricted to reference(s): "HO"
There are 46 results within The Catalogue. Hits 1 to 20 are shown below sorted by catalogue reference. snipped


HO 46 Home Office: Daily Registers of Correspondence 1841-1957
HO 101 Home Office: Ireland: King's Letter Books 1776-1955
might be worth searching

regards

Hugh W