Yellow-belly, Yellow-peril, Yellow-fever, Yellow-streak.

During the Age of Enlightenment a Parisian Jesuit priest named Louis Betrand Castel researched the relationship between light and sound. In 1730 this study culminated in Castel designing his own Ocular Harpsichord.

The ocular harpsichord consisted of a frame with 60 small coloured windows that sat above a regular harpsichord. Each window was covered by curtains which in turn were connected to an individual key. Whenever a key was struck a curtain would open revealing a coloured window that corresponded with Castel’s theory relating colour to sound.

According to Castel the colour yellow related to the note “E”.

With his new harpsichord Castel not only hoped that the colours would enhance the fleeting world of sound, but that sound would also intensify colour:

The principal advantage of this new harpsichord is thus to give to the colours, apart from their harmonic order, a certain vivacity and lightness which on an immobile and inanimate canvas they never have.

A caricature of Castel and his ocular harpsichord (Charles Germain de Saint Aubin, 1700s).

Castel believed that the ocular harpsichord would eventually reside in every Parisian home yet to this day no remaining artefact of his invention is known to exist.

Yellow: the colour of instability, flitting from freshness to decay. It is the colour of joy and jealousy.

Yellow: the colour worn by Judas Iskarios at the last supper; it is the colour of falsehood and cowardice.

Yellow: the colour of exclusion; it is the colour marking the Other.

The Sound of Yellow: it is the sound of lightness, of pulsating energy; it is a sound that lifts but does not embrace. I listen to the sound of yellow and am moved by its luminosity, its tone is to be admired from a distance.