From John Robertson9
AL: American Philosophical Society
<The Royal Society, July 14, 1772, a note in the third person. The committee appointed by the Society, at the request of the Board of Ordnance, to suggest how to apply lightning rods to the powder magazine at Erith1 is requested to meet at the Society’s quarters in Crane Court on Saturday, July 18,2 at seven P.M.; Franklin’s presence is desired.>
9. A mathematician, F.R.S. since 1741 and clerk and assistant secretary of the Royal Society since 1768; see above, XIV, 351 n.
1. Erith is on the south side of the Thames, below Woolwich and just across the river from Purfleet. We have assumed that Henly was using the two place names synonymously in his letter to BF above, under May 4; Robertson was clearly doing so because, although a royal magazine at “Erith Level” in Kent is mentioned in 12 Geo. III, c. 61, the committee was charged with investigating Purfleet.
2. The earliest extant minute of the committee’s deliberations was dated Aug. 12, and it reported on Aug. 21; see below.