was a musician, engineer,
inventor ... and exceptional.
By Michael Betancourt
Even today, Mary Hallock-Greenewalt (1871–1950)
would be unusual, but in the early years of the
20th century, she was exceptional. Between 1919
and 1927 she filed 11 patents, while performing
as a piano soloist with both the Philadelphia and
Pittsburgh orchestras, recording with Columbia
Records, and producing hand-colored “films”
along with a machine that timed them to play
in sync with music.
Photograph courtesy of The Historical Society of Pennsylvania
Hallock-Greenewalt’s various patents described
the components for a new, technological art form
she called Nourathar, derived from the Arabic for
“essence of light.” Her instrument for performing
this light music, the Sarabet, employed mercury
switches, motor-controlled lights, and rheostat
switches, aka dimmers. Her patents were so revolutionary that they were almost immediately stolen
for use in theatrical lighting manufactured by
General Electric. She sued GE for patent infringement, ultimately winning on appeal — the first judge
didn’t believe that as a woman, she had invented so
complex an electrical device as the rheostat.
Hallock-Greenewalt’s Sarabet, named in honor
of her mother Sarah Beth, underwent continuous
refinement and tinkering. She often changed the
placement and number of lamps to achieve a full
coverage of the performance space’s geometry and
architecture. The Sarabet controlled a network of
1,500-watt lights that could be dimmed individually
and turned red, orange, yellow, green, blue, or violet
by filters on color wheels. More complex hues were
mixed on the performance screen.
In place of a keyboard, the Sarabet had a console
with graduated sliders and other controls, more like
a modern mixing board. Lights could be adjusted
directly via the sliders, through use of a pedal, and
with toggle switches that worked like individual
keys. Three banks of light controls corresponded to
the physical lamp placement throughout the performance space: front, center, and rear. Since her
performances often took place in movie theaters
and used the movie screen, this division could also
correspond to top, middle, and bottom.
Significantly, Hallock-Greenewalt recognized that
there is no inherent relationship between color and
music, that color does not have an octave and projected light has no analog to musical harmony. This
contrasts with contemporaries such as A. Wallace
Rimington who developed more restricted forms of
visual music. But the Sarabet did prevent multiple
colors from being shown at the same intensity at
the same time; each position in her scale — starlight,
moonlight, twilight, auroral, diurnal, and superbright
— allowed for only one lamp set at that level.
Nourathar performance was environmental,
rather than image or symbol-based. While it was
possible to pair these lamps with gobo templates to
give shape to the light, Hallock-Greenewalt instead
focused on fields of color, more like the abstract
expressionists who were to follow, decades later.
Michael Betancourt is an artist, curator, editor, and theorist
whose essays have appeared in Leonardo, Semiotica,
CTheory, and other academic journals.