The square piano was intorduced to London in the mid 1760s by Johannes Zumpe, and quickly became very popular. When the demand became too much for Zumpe to meet, it was his compatriot Johannes Pohlman who was the first to join him; the earliest known Pohlman piano is dated 1767.
As is so often the case, the second to the market has to try harder, and there are many Friends (myself included) who think that Pohlman's pianos are rather better designed and built. But everbody wants a Zumpe!
This handsome piano was made twenty years later, in 1787, and is unusual in having the date on the nameboard as late as this; the next latest example to present a date was made in 1778.
But what is really unusual is the damper mechanism.
The damper-unit is separate from the keys, which are shorter than usual. It consists of weighted levers pivoted near their mid point. When the back of the key rises, the far end of the lever drops, allowing the UNDER damper to clear the string. At rest, the weight keeps the damper in contact with the string.
I have no personal experience of this system, but it seems to me that, relying on gravity, it is potentially more reliable and quieter than the usual spring-loaded overhead lever dampers. The nearest parallel to this system that I can find is the under-damper acti0n patented by James Ball in 1790 (recorded in Michael Cole's book) but the Pohlman version seems to me to be much better engineered, and three years earlier. Of course, we know now that it was not widely adopted - perhaps it was just too expensive to make?
So as far as we know, this is the unique surviving example of an ingeneous innovation.
This piano has three pedals (seen in the opening picture - reconstructed c. 2003) . As well as the dampers, these operate a lid-swell (not currently working) and a sort of mute - fitted to the edge of the wooden shelf seen in the above picture.
It was restored in the early years of the present century, and was in playing order for some time. The piano does now need major work, principally to the structure of the right-hand end.
The separation seen in the picture above is quite common in very early pianos, but is actually preferable to the dreaded 'twist'. In the latter case, the wood itself is distorted, and the problem is difficult to cure. But the separation seen in this one, although it means removal of the soundboard and rebuilding of the structure, should lead to an 'as good as new' outcome.
Otherwise, some work is needed to the hammers and action. The soundboard is said to be original, but has been extensively repaired.