Minutes of the Committee on the Purfleet Magazine
Copy: the Royal Society; partial copy: American Philosophical Society
August 12–21, 1772.
<August 12: The Committee agreed to the following:7 lightning conductors were necessary; they should be placed at each end of each magazine, reaching ten feet above the ridgepole and connecting at the bottom with wells filled with water; the top of the chimney of the Proof House should be connected by lead with the conductor at the end of the adjacent magazine.8
August 17: The committee met with Dr. Maty, the secretary of the Royal Society, and agreed that the Board House and Clock House should have conductors. Franklin read a draft of the committee’s report, to which all agreed except Benjamin Wilson.
August 18: The committee again met with Maty, Franklin read part of a final draft, and Wilson objected to the use of pointed conductors. Franklin was requested to finish the draft.
August 21. The committee, in Maty’s absence, heard Franklin read the final report, in which he inserted a provision for a pointed conductor on the Board House. Wilson protested in writing against the use of such conductors. All the others signed the report, which was to be presented to the Council of the Society.>
7. For the names of the committee and details of the recommendations summarized here see the full report below, Aug. 21.
8. A copy of the minutes of Aug. 12, corrected by BF, is among his papers; it here adds the recommendation embodied in the later report, that the two outermost magazines should each have an extra conductor in the middle of the building to connect the ridgepole with a well.