In this late 1700's map we see Tenter Ground. This is where woven silk was stretched out on tenterhooks. This where we get the phrase 'being on tenterhooks' - being stretched in anticipation. The word tent of course, implies cloth over supports.
Spital Square is towards the top left of this map.

Spitalfields lies outside of the old walls of the City of London on the east side of the Roman Ermine Street (now Bishopsgate Street.) This road ran from the Port of London on the Thames, to Lincoln and York. Spital Square is very close to Bishopsgate Street, thus useful for travel and really close to the City of London where the Banking quarter is. We know that the de Brissac family had banking connections from their time in Utrecht. Threadneedle Street (now London’s banking quarter) is within easy walking distance and was also a family home address. (Less of a mile west of this map)