Is it farther or further?
late 15c., from Middle French palpation, from Latin palpationem (nominative palpatio) "stroking, flattering, flattery," noun of action from past participle stem of palpare "to touch" (see feel (v.)). Used in English in literal sense.
palpate pal·pate (pāl'pāt')
v. pal·pat·ed, pal·pat·ing, pal·pates
To examine by feeling and pressing with the palms of the hands and the fingers.