When the the piano was first developed back in the 18th century by Bartolomeo Cristofori, the famous Italian Harpsichord maker, the idea was to make it like a harpsichord with both loud and soft sounds. The strategy for creating it was taken from a combination of the clavichord’s expressive attributes and the magnificence of the harpsichord. This resulted in a wonderful pianoforte that could play a range of loud to soft notes.
The use of hammers on the piano forte were a substitute for the harpsicord’s quills, and the piano player’s applied force to their fingers according to the depth of volume they required. The piano’s hammer briefly struck the strings and that allowed them to vibrate freely. After this action, dampers were used to fall onto the strings and thereby immediately stop the vibration and associated sound. Two of Cristofori’s beautifully crafted instruments can be viewed in the Metropolitan Museum in New York, and in Leipzig, Germany.
Cristofori’s master invention was used by the famous clavichord and organ constructor, Silbermann, who made two of them in the 1720s, and later gave them as gifts to Bach. A few adjustments needed to be made, and in Potsdam the late 1740s, Bach used a Silbermann pianoforte to entertain Fredrick the Great. Every pianoforte until this period was shaped like a harpsichord, just as with the grand pianos of our time.
By the start of the 19th century, the pianoforte evolved, and this resulted in different forms and shapes. The ones which received most attention, were the giraffe (cabinet) piano, the the now standard square piano, as well as pianos with an iron frame to provide a robust base. In the case of the latter, the tone and sound were generated via the wood (sound board), at the rear of the strings.