Karl Glogauer rides from 1966 to 28 A.D. by traveling in a rubber suit, breathing through a mask connected to a hose leading to the wall of a machine with “cryptographic, unconventional” controls that is womb-like, spherical, and partially filled with a milky fluid (p. 78 - Dying for Tomorrow, 1st DAW printing, 1978) and (p. 13 - Novel, 1st Avon Printing, 1970). Upon its crash landing, the machine cracks open like an egg, spilling out its fluid and permitting Karl his entry into the past. It was invented by Sir James Headington.
An identical machine was used by Jherek Carnelian to travel to the 19th Century.
In Flux the machine is composed of a power unit—i.e., an electronic network of trestles and helices on the floor of a room that was immobile in space and time—and a separate steerage unit—i.e., a spatio-temporally mobile chair to which was affixed three translucent rods (that represent the three spatial dimensions) and a swivel arm that held a box of control dials and switches.