shaky-bog n [phonetics unavailable] OED shake sb1 13 shake-bog (1815), EDD shake v 1 (13) ~ bog; Kilkenny Lexicon ~. A stretch of marshland or bog with springy surface.
1869 HOWLEY MS Reminiscences 3 Though quite dry when we pitched our camp [the swampy hollow] soon became a perfect shakybog in which one would sink to the knees in wet muck. P 148-62 ~ low-lying piece of land ' wet ' with grass and weeds. C 71-93 ~ Ground above a spring, thus called because when one walks upon it it shakes. P 141-73 As one walks over the wet bog, it shakes under one's feet, and this kind of bog we called shaky-bog.
