title: True vertical laser.
abstract: A new laser configuration has been devised utilizing a mercury mirror as one reflector. When the laser is oriented vertically, lasing occurs. This beam can thus be used for the precision alignment of vertical structures.
authors.forename: K W
authors.initials: KW
authors.lastname: Billman
authors.forename: E T
authors.initials: ET
authors.lastname: Leonard
authors.forename: M A
authors.initials: MA
authors.lastname: Yaffee