A model developed by co-author Robertus Erdélyi of the University of Sheffield, U.K., shows that certain alignments of the sun's magnetic fields can channel the vibrations through narrow tunnels in the fields, driving spicules upward like regular thrusts from a piston. (sciencemag.org)
In Ho Chi Minh City, your sightseeing includes the War Remnants Museum, and the Cu Chi region, where you'll get to explore the deep, narrow tunnels constructed by the Viet Cong during the war. (deltavacations.cosmos.com)
You sit quite low in a not - too - narrow tunnel clad with dark manmade materials. (automobilemag.com)