The section of The National Gazetteer (1868) relating to Caernarvonshire - transcribed by Colin Hinson.
Tallis's Topographical Dictionary of England and Wales, published in 1860 in six vols, editor E. L. Blanchard.
See Welsh Family History Archive for all the excellent county maps (showing the hundreds) and the alphabetical gazetteer
From the preface;
"In the following pages will be found fully described the past history and present aspect of every place of any significance in England and Wales, forming a work of permanent importance to the commercial world, of ready service to the tourist of the day, and of constant interest to the general reader, who may derive from this source a large supply of entertainment, as well as of information for the amusement and instruction of a leisure hour."