Editing Piano (section)

===Variations in shape and design===
Some early pianos had shapes and designs that are no longer in use. The [[square piano]] (not truly square, but rectangular) was cross strung at an extremely acute angle above the hammers, with the keyboard set along the long side. This design is attributed to [[Christian Ernst Friderici]] (a pupil of Gottfried Silbermann) in Germany and [[Johannes Zumpe]] in England,{{sfn|Dolge|1911|p=48}} and it was improved by changes first introduced by [[Guillaume-Lebrecht Petzold]] in France and [[Alpheus Babcock]] in the United States.<ref>{{Cite journal |last=Grafing |first=Keith|date=1974|title=Alpheus Babcock's Cast-Iron Piano Frames|journal=The Galpin Society Journal |volume=27 |pages=118–124|jstor=841758|doi=10.2307/841758 |issn=0072-0127 }}</ref> Square pianos were built in great numbers through the 1840s in Europe and the 1890s in the United States, and saw the most visible change of any type of piano: the iron-framed, over-strung squares manufactured by Steinway & Sons were more than two-and-a-half times the size of Zumpe's wood-framed instruments from a century before. Their overwhelming popularity was the result of inexpensive construction and price, although their tone and performance were limited by narrow soundboards, simple actions and string spacing that made proper hammer alignment difficult.

[[File:Upright piano inside.jpg|thumb|left|The mechanism and strings in upright pianos are perpendicular to the keys. The cover for the strings is removed for this photo.]]
The tall, vertically strung upright grand was arranged like a grand set on end, with the soundboard and bridges above the keys and tuning pins below them. "[[Giraffe piano]]s", "[[pyramid piano]]s" and "[[lyre piano]]s" were arranged in a somewhat similar fashion, using evocatively shaped cases. The very tall cabinet piano was introduced about 1805 and was built through the 1840s. It had strings arranged vertically on a continuous frame with bridges extended nearly to the floor, behind the keyboard and very large ''sticker action''. The short cottage upright or ''pianino'' with vertical stringing—made popular by [[Robert Wornum]] around 1815—was built into the 20th century. They are informally called ''birdcage pianos'' because of their prominent damper mechanism. The oblique upright, popularized in France by [[Blanchet (harpsichord makers)|Roller & Blanchet]] during the late 1820s, was diagonally strung throughout its compass. The tiny [[spinet]] upright was manufactured from the mid-1930s until recent times. The low position of the hammers required the use of a "drop action" to preserve a reasonable keyboard height. Modern upright and grand pianos attained their present, 2000-era forms by the end of the 19th century. While improvements have been made in manufacturing processes, and many individual details of the instrument continue to receive attention, and a small number of acoustic pianos in the 2010s are produced with [[MIDI]] recording and digital [[sound module]]-triggering capabilities, the 19th century was the era of the most dramatic innovations and modifications of the instrument.