Despite his English-sounding name, James Ball was one of the community of German-born piano-makers who established themselves in London in the later part of the eighteenth century. He was active from about 1780.
This example from the early part of the nineteenth century rests on a good French stand, and has Southwell-type 'dolly' dampers.
It has evidently suffered structural problems at some stage, and it will now be necessary to remove the soundboard for repair and attention to the interior joints. Good news is that it looks as if the bridge itself might be OK.