Someone mentioned the Internet Archive on another list. This has complete
scanned copies of out of copyright books that can be read on line or
downloaded as a PDF file.
I find that it is best to search with Media Types set to "Texts".
http://www.archive.org/advancedsearch.php
http://www.archive.org/bookmarks/J%20M%20Briscoe
Quite a number relevant to North Wales ...
Title Biographical dictionary of ministers and preachers of the Welsh
Calvinistic Methodist Body [microform] : or Presbyterians of Wales; from the
start of the denomination to the close of the year 1850
Creator Evans, Joseph
Publisher Carnarvon, [Wales] : D. O'Brien Owen, C. M. Book Agency
Date 1907
Title The Welsh vocabulary of the Bangor district
Creator Fynes-Clinton, Osbert Henry
Publisher London H. Milford, Oxford University Press
Date 1913
Martin Briscoe
Fort William
M&LFHS | Gwynedd FHS