Figure 32 shows the fretted clavichord keyboard in more detail. Tangents on keys numbered 16 and 17 strike the same strings to produce the notes e♭ and e. Some other fretted notes shown in the picture include: keys 18 and 19 (f and f♯), keys 20 and 21 (g and g♯]), keys 23 and 24 (b♭ and b), and keys 25 and 26 (middle c and c♯). Figure 31 is also a detail from this clavichord. The Smithsonian clavichord shown in Figures 35 and 36, in unrestored condition, is typical of the large unfretted instruments that became standard in Germany by the mid-18th century and for which Carl Philipp Emanuel Bach wrote many solo keyboard compositions. [Illustration: 32. Fretted clavichord: Detail of fretting. _Photo: Robert Lautman_.] [Illustration: 33. Fretted clavichord: Full view.] [Illustration: 34. Fretted clavichord: Plan view.] [Illustration: 35. Unfretted clavichord: Full view.] [Illustration: 36. Unfretted clavichord: Plan view.] By the beginning of the 18th century the desire was strong for a more expressive keyboard instrument to use in ensembles. Harpsichord builders added new stops, devised special leather plectra, and added Venetian swell effects and other innovations to alter the sound of the harpsichord. But no matter what they did, they could not produce enough dynamic gradation to satisfy musical taste. The clavichord was capable of dynamic nuance, but it lacked carrying power. Instrument builders, seeking to satisfy the demands created by the change in sensibility and musical taste, turned naturally to the domestic instruments they knew best—the harpsichord and clavichord—as the process of adaptation began. For this reason, as the pianoforte was developed and perfected, the general proportions and arrangement of the grand piano resembled those of the harpsichord. Similarly, the relation between the keyboard and strings, the scaling, and other features of the square piano resembled those of the clavichord. By the beginning of the 19th century the pianoforte, an instrument capable of subtle changes between soft and loud, had become the most important domestic and concert keyboard instrument. After 1800 few clavichords or harpsichords were built or used until they were revived by early music enthusiasts at the end of the 19th century. _Selected Bibliography_ BOALCH, DONALD. _Makers of the Harpsichord and Clavichord_. London: George Ronald, 1955. HIRT, FRANZ JOSEF. _Meisterwerke des Klavierbaus_. Olten, Switzerland: Urs Graf-Verlag, 1955. HUBBARD, FRANK. _Harpsichord Regulating and Repairing_. Boston: Tuner’s Supply, Inc., 1963. HUBBARD, FRANK. _Three Centuries of Harpsichord Making_. Cambridge, Massachusetts: Harvard University Press, 1965. JAMES, PHILIP. _Early Keyboard Instruments_. London: Peter Davies, 1930. RIPIN, EDWIN M. “The Early Clavichord,” _Musical Quarterly_, 53(4) (October 1967): 518-538. RUSSELL, RAYMOND. _The Harpsichord and the Clavichord_. London: Faber and Faber, 1959.