Note 532 — Chapter XIII · SHOCK PROJECTILES
Reading edition
This gives a sp. gr. of 3.1, and shows that the stone was probably limestone, although Nye objects to “freestone” for shot and recommends “marble, pibble stones, and hard blew stones,” p. 58. “Pibbilston” is found in Wiclif´s Bible, Prov. xx. 17, cir. 1383.