 Many of these early sump explorers adopted an approach based upon a sturdy belt, with attached cam-band, that allowed a cylinder to be dropped in and carried alongside the outer thigh.This allowed them to crawl, or wriggle, through the dry cave sections, whilst presenting a secure method of attachment for passing through submerged areas.Swimming efficiency, reduced water resistance, trim and buoyancy control were not generally required due to the nature of those caves.