CHAPTER X.

ON WORKING IN IRON 79 Hand Forging 79 Welding 79 Hardening Iron by Hammering 80 Case-hardening 81 A Good Way to Case-harden 82 Material for Case-hardening 84 Another Way to Case-harden 85 Another Formula for Case-hardening 86 Still Another Formula 87 To Chill Cast Iron 87 Another Mode 87 To Soften Wrought Iron 87 Alloy for Filling Holes in Iron 87 To Harden Iron for Polishing 88