Somerset returned sixteen members to Parliament: two for the county and two each for Bridgewater, Ilchester, Milborne Port,Minehead and Taunton, and Bath&Wells. Milborne and Minehead lost their seats in the electoral reforms of the 1830's, as, I believe, did Ilchester. However, it should be noted that none ofthese were so-called "pocket boroughs". Perhaps it's worth noting that Bristol also returned two members, and part of Bristol was in Somerset.
Cleveland 's location really mixes things up- it's eighty miles form Barton and thirty from Coombe Magna- one of JA's geographical impossibilities again! Somerset is just not that big that any part of it could be eighty miles from a village "four miles northward of Exeter"