Guildhall is the chief town.  This county is bounded north by Canada, east and south by Connecticut River, which separates it from Coos County, New Hampshire, south-west by Caledonaia County, and west by Orleans County.  It is about forty-five miles long from north to south, and twenty-three broad from east to west.

   This county is the least populous in the State, with the exception of Grand Isle County.  There are some towns which are entirely destitute of inhabitants.  The settlements are mostly confined to the towns lying along Connecticut River.  The county is in general very uneven and the soil rock and unproductive.  It comprehends that part of the county called Upper Coos, which lies on the west side of Connecticut River.  Nulhegan River is the principal stream, which is wholly within the county.  This and several smaller tributaries, of the Connecticut, water all of the eastern parts.  Passumpsic and Moose River, rise in the south-western part, and Clyde River and several streams, which run off to the north into Canada, water the north-western parts.  Essex County presents a great variety of magnificent scenery.
 

(Gazetteer of Vermont, by John Hayward, 1849, p. 58)