Note 2 — Part II.
Reading edition
A system of Pendulums tuned to swing the various ratios of the musical scale, form a “Silent Harp” of extraordinary interest. This “Silent Harp,” D. C. Ramsay, of Glasgow, has shown to his students of harmony for many a year. A pen, placed by means of a universal-jointed arrangement between any two pendulums of this “Silent Harp,” so as to be moved by a blend of their various motions, writes, with all the precision of gravitation, a portrait of the chord which two corresponding strings of a sounding harp would utter to the ear. This spiral writing is a Pendulograph; exquisite forms such as no human hand could trace. ↑