Letters (2) 1871 Oct, Denmark Hill [to] J.C. Bayley/Henry Bessemer

[Letters (2)] 1871 Oct, Denmark Hill [to] J.C. Bayley/Henry Bessemer. [First letter discusses importance of removing phosphorous during steel-making and hints that Bessemer is approaching a breakthrough in his own process; second letter compares Webster's patent 2364/1868 with Bessemer's prior patent covering the use of acidic or hydrocarbon gases in steel refining.]