The Collaborative International Dictionary of English v.0.48:

Immerge \Im*merge"\, v. t. [imp. & p. p. Immerged; p. pr. &
   vb. n. Immerging.] [L. immergere; pref. im- in + mergere to
   dip, plunge: cf. F. immerger. See Merge, and cf.
   Immerse.]
   To plungel into, under, or within anything especially a fuid;
   to dip; to immerse. See Immerse.
   [1913 Webster]

         We took . . . lukewarm water, and in it immerged a
         quantity of the leaves of senna.         --Boyle.
   [1913 Webster]

         Their souls are immerged in matter.      --Jer. Taylor.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Immerge \Im*merge"\, v. i.
   To dissapear by entering into any medium, as a star into the
   light of the sun. [R.]
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "immerge":
   baptize, bury, deluge, dip, douse, drown, duck, dunk, engulf,
   immerse, inundate, merge, overwhelm, plunge in water, sink, souse,
   submerge, submerse, whelm