Mass chord or signature.

"The mass chord of any mass is that lowest or fundamental vibration to which that mass is resonant." [MASS CHORDS]

"Each molecule of a given mass of matter represents the same harmonic chord or note in its oscillatory motion. The "chord of the mass" is, therefore, the chord of every molecule of the mass." [Laws of Being]

"Each molecule of a given mass of matter represents the same harmonic chord or note in its oscillatory motion. The "chord of the mass" is, therefore, the chord of every molecule of the mass. [KEELYS PHYSICAL PHILOSOPHY - Snell]

The Fundamental
Taking a wine glass as an example it can be ruptured into pieces by tuning an outside acoustic influence to its fundamental pitch then amplifying it until the wine glass shatters. A spectral analysis of the wine glass prior to shattering will reveal its chord or signature meaning all the pitches to which it is resonant or responsive. One of these pitches of its spectra is its fundamental tone to which it is most sensitive and responsive. According to the definitions above this most sensitive pitch is its "chord of mass".

The Chord
A chord is a combination of discrete frequencies, harmonics and partials. Every sound is in actuality a chord composed of discrete aliquot or component tones synthesized together into the form of the chord. For instance the musical note "C" may be sounded on a trumpet and on a piano and the ear can readily tell the difference in tone quality. This difference is caused by the discrete aliquot or component tones synthesized together. This complex waveform is called "complex waveform", "Signal", "Spectra", "Spectrum", "Signature", "Envelope", "Frequency Domain" or "Time Domain".

The chord of a mass or its signature may be restricted to its Frequency Domain or Time Domain which is the standard method. However there are other important variables or considerations in a material substance. These additional variables would emcompass but not be limited to the other seventeen dimensions or variables as mentioned by Walter Russell. These all taken together would constitute the objects wavefunction to be discussed in the next chapter.

Spectrum Analyzer
A spectrum analyzer is an electronic digital instrument (there have been analog spectrum analyzers) which can detect all the vibrations of the excited wine glass then using specialized mathematical tools (such as Fourier Transform) separate the discrete pitches from each other thus revealing the complete set of frequencies making up the "chord of the mass" of the wine glass.