A small polygonal virginal built by Franciscus Bonafinis in 1585 was ingeniously converted to a tangent piano in 1717; this was accomplished simply by replacing its jacks with shorter slips of wood and moving its strings so that they lie directly over the jack slots, producing an instrument with struck rather than plucked strings whose sound varies in loudness with the force applied to the keys. The instrument is now at the Metropolitan Museum.
Instruments employing this principle were well-known in the eighteenth century—the trend culminated in the Späth & Schmahl Tangentenflügel.
This according to “En route to the piano: A converted virginal” by Edwin M. Ripin (Metropolitan Museum journal XIII  pp. 79–86).
Above, the Museum’s depiction of the instrument; below, Aleksej Borisovič Lûbimov performs on a tangent piano.
In 1940 Alexander Rose (1901–85, above) received a U.S. Patent for his Typatune, a toy piano with a QWERTY typewriter keyboard. He seems to have been destined to create this curious invention both through his vocation as a court stenographer and his choice of a wife—one Clara Berger, daughter of Samuel Israel Berger, a noted maker of toy typewriters.
World War II may have caused a moratorium on the Typatune’s manufacture, as the toy did not appear on the market until shortly before Christmas 1945, when it was widely advertised.
The purchaser of a Typatune also received a spiral-bound booklet showing which keys to press to produce a number of popular melodies. Two models have been identified—one in a red rexine case and one in an off-white wooden case, both with a collapsing carry-handle. A later development was the addition of a hinged lid to protect the keyboard. All versions carry the label Made in Switzerland.
This according to “Neither one thing nor the other: Alexander Rose’s Typatune” by Arthur W.J.G. Ord-Hume (The music box: An international journal of mechanical music CCVIII [summer 2017] pp. 48–50).
Below, a brief demonstration with an inside view.
In designing his oval spinet, Bartolomeo Cristofori (1655–1731) sought to produce a relatively small instrument with long bass strings, two 8′ registers with a difference in timbre equal to that obtainable with a harpsichord, a symmetrical distribution of the tensions on the soundboard, and an aesthetically appealing and elegant appearance.
The longest string is placed in the center of the soundboard, while the strings move towards the acute in symmetrical alteration to the left and to the right; they therefore require a complicated action system for the movement of the key levers to be transmitted to the appropriate jacks.
All of the first register’s strings are arranged in order towards the back side, while the second register’s strings progress from the center towards the front side—it is the two registers, and not the sequence of notes, that are symmetrical with respect to the center. The selection of the registers is accomplished by sliding the keyboard, which activates a counter-lever system.
This according to “Bartolomeo Cristofori: La spinette ovali del 1690 / Bartolomeo Cristofori’s 1690 oval spinet” by Gabriele Rossi-Rognoni, an essay included in Bartolomeo Cristofori: La spinetta ovale del 1690—Studi e ricerche / The 1690 oval spinet—Study and research (Firenze: Ministero per i Beni e le Attività Culturali, 2002).
Above, a replica built by Tony Chinnery and Kerstin Schwarz. Below, a brief documentary on Cristofori and his instruments.
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