||Hallet Davis & Co.
This section of a piano shows many details of construction. Instead of the common bridge notching and pins to align the strings, Hallet, Davis and Co. made a series
of pianos with agraffes defining both ends of the speaking length of the wire.
Zoom in on the bass bridge agraffe to see the slots they had made to allow for a wound string to get into position.
This is what is known as an open faced block used in so called 3/4 plate pianos. Note how the plate has an internal flange around which the wooden parts of the structure were screwed and glued.