surface in the boiler to suffice. 
Conchoidal propeller. 
Condensation of steam, water required for. 
Condenser, description of,
  action of;
  proper dimensions of. 
Condenser of oscillating engine. 
Condenser of direct acting screw engine. 
Condensing engine, definition of. 
Condensing water, how to provide when deficient. 
Conical pendulum or governor. 
Connecting rod, description of,
  strength proper for. 
Connecting rod of direct acting screw engines,
  of locomotives. 
Consumption of fuel on each square foot of fire bars in wagon, Cornish,
    and locomotive boilers. 
Copper, strength of. 
Corliss’s steam engine. 
Corrosion produced by surcharged steam. 
Corrosion of marine boilers,
  causes of. 
Cost of locomotives. 
Cotton spinning, power necessary for. 
Counter for counting strokes of an engine. 
Crank, description of,
  unequal leverage of, corrected by fly wheel;
  no power lost by;
  action of;
  strength proper for. 
Crank of direct acting screw engines. 
Crank pin, strength proper for. 
Crank pin of direct acting screw engines. 
Cranked axle of locomotives. 
Cross head, description of,
  strength proper for. 
Cross head of direct acting screw engines. 
Cross tail, description of. 
Cylinder, description of,
  strength proper for. 
Cylinder of oscillating engine,
  of direct acting screw engine. 
Cylinders should have a steam jacket, and be felted and planted,
  should have escape valves. 
Cylinders of locomotives should be large,
  proper arrangement of. 
Cylinders, how to cast,
  how to bore;
  how to grind. 
Cylinder jacket, advantages of.

Damper. 
Dampers, various forms of. 
Deadwood, hole in, for screw. 
Delivery valve, description of. 
Delivery or discharge valves, proper dimensions of. 
Delivery valves might be made on Belidor’s plan. 
Delivery valves in mouth of air pump,
  of india rubber. 
Direct acting screw engines should be balanced. 
Direct acting screw engine by Messrs. John Bourne &, Co.,
    cylinder;
    discs;
    guides;
    screw shaft brasses;
    air pump;
    slide valve;
    balance piston;
    connecting rod;
    piston rods;
    cross head;
    air pump arm;
    feed pump;
    crank pin;
    screw shaft;
    thrust plummer block;
    link motion;
    screw propeller. 
Discharge valves. 
Disc valves of india rubber for air pumps. 
Discs of direct acting screw engine instead of crank. 
Dodds, expansion valve by. 
Double acting engines, definition of. 
Double acting air pumps,
  valves of;
  faults of. 
Draw bolt. 
Dredging earth out of rivers, power necessary for. 
Driving wheels of locomotives. 
Driving piles, power necessary for. 
Duplex pump, Worthington’s. 
Dundonald, Earl of, screw by. 
Duty of engines and boilers,
  how the duty is ascertainable. 
Dynamometer, description of. 
Dynamometric power of screw vessels.