CHAPTER IX.

HARD-STEAMING ENGINES 92

Importance of Locomotives Steaming Freely.--Essentials for Good-steaming Engines.--Causes Detrimental to making Steam.--Petticoat-pipe.--The Smoke-stack.--Obstructions to Draught.--Choking the Netting with Oil.--Silicious Deposit on Flue-sheet.--The Extended Smoke-box.-- Steam-pipes leaking.--Defects of Grates.--Lime, Scale, and Mud.--Preventing Accumulation of Mud in Boilers.-- Temporary Cures for Leaky Flues.--Good Management Makes Engines Steam.--Intermittent Boiler-feeding.--Too Much Piston Clearance.--Badly Proportioned Smoke-stacks.--The Exhaust Nozzles.