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VI.

Injuries of engines and boilers. 1.-Boiler explosions. -Two kinds, by rupture and by bursting; causes and means of

prevention. Escape of water by the safety-valve. Explosive combinations in

the flues. 2.-Spontaneous combustion of coal. Causes. Indications of the heating of coal;

precautions to be taken. Fire in the coal-bunkers. 3.-Injuries to the cylinder; measures to be taken for working the engine with the

parts left intact; engine with simple cut-off, Multiple-cylinder continuous-expansion engine. Woolf engine, with cranks at 90°. Three-cylinder engine, with cranks at 900 and 135o.

NOTE M.

BILL OF FARE.

Menu des repas des élèves pour la journée du 18 juin 1878 et pour le lendemain matin.

DÎNER.

Potage au vermicelli.

Beuf aux choux.
Petits pois au beurre.

Fraises.

SOUPER.

Mouton rôti.
Pommes de terre (maitre d'hôtel).

Compote de prunes.

DÉJEUNER

Café au lait.

Beurre.

NOTE N.

PROGRAMME OF EXAMINATIONS.

SCHOOL OF MACHINISTS, FRENCH NAVY.

CANDIDATES FOR FIRST MASTERS.

CHAPTER I.

Arithmetic, algebra, geometry, plane trigonometry.
Square and square root of whole numbers.
Square and square root of fractions.
Cube of whole numbers and fractions.
System of weights and measures.

Relation between the metric system and the English system of weights and measures.
Ratio and proportion.
Arithmetical and geometrical progression.
Theory of logarithms. Use of tables.
Elementary processes of algebra.
Solution of equations of the first degree with one or more unknown quantities.
Solution of equations of the second degree with one unknown quantity.
Properties of right lines and of angles.
Equality of triangles.
Properties of parallel lines, rectangles, and polygons; of the circle; properties of

chords, secants, and tangents.
Measurement of angles. Relative position of two circumferences.
Proportional lines. Similar polygons.
Problems of plane geometry.
Regular polygons. Measurement of plane surfaces; of the circumference and of the

area of a circle.
Parallel and perpendicular planes and right lines. Dihedral angles.
Properties of prisms and pyramids. Superficial area and volume. Volume of the
frustum of a prism, parallelopiped, and pyramid. Superficial area and volume of

a cylinder, of a cone, of the frustun of a cone, and of a sphere.
Solid contents of a coal-bunker.
Definitions of the principal trigonometric lines.
Solution of right triangles.

CHAPTER II.

Mechanics and physics. Elementary notions of matter; inertia, motion, velocity, Forces; weight and density of bodies. Measurement of force. Mass and its deter

mination. Composition of concurrent forces. Decomposition of a force into two others acting in

any given direction. Composition of parallel forces. Centers of gravity. Practical determination of the center of gravity of any body

whatever. Determination of the centers of gravity of geometrical surfaces and the

principal solids. Work of forces; its graphical representation and measure. The kilogrammeter and

the horse-power. Principle of the transmission of work in the case of a uniform motion : Application to the equilibrium of simple mechanics. Passive resistances. Necessity of regulating the motion of machines. Fly-wheels. The efficiency of a machine. Action and equilibrium of the lever; of pulleys. The differential pulley. Action of the connecting-rod, of the crank, of the eccentric, and of cams. Action, equilibrinm, and drawing of parallel and conical toothed wheels. Action and equilibrium of the screw; of the endless screw. Watt's parallelogram. Equilibrium of the inclined plane and of the wedge, taking into account the effect of friction; of the winch, and of the windlass or capstan. The differential windlass. Strength of materials. Equality of pressure of Auids. Calculation of the pressure exerted upon a given sur

face.

Air, atmospheric pressure. Different methods of determining pressure in engines. Vacuum, and methods of determining it. Construction and use of the barometer. Effects prodaced upon bodies by the increase or diminution of heat. Construction and use of the thermometer. Expansion and contraction of metals. Precautions to be taken in consequence of the expansion and contraction of metals in the construction, erection, repair, and management of engines. Shrinkage, tempering, anhealing. Expansion of fluids. Particular effects of the action of heat on water.

Measurement of heat. Calorific capacity or specific heat of bodies, latent heat.

Propagation of heat. Effects of surfaces of various colors and of polished surfaces. Good and bad conductors. Heating of liquids by circulation. Means of preventing loss of heat, and the overheating of furnace doors and chimneys. Principle of transformation of heat into work, and vice versa. Mechanical equivalent of heat.

Carnot's theorem. Fundamental principles of boilers, combustion, furnaces. Gases: expansion, tension. Mariotte's and Gay-Lussac's laws. Theory of the siphon. Theory and description of the suction-pump; of the force-pump, and the double-acting

pump; of centrifugal and rotary pumps. Hydranlic press. Evaporation, vaporization, boiling, conversion into steam. General properties of

steam. Saturated steam, heated and superheated steain. Spheroidal condition

of water. Bourdon's manometer. Compressed-air manometers. Condensation of steam. Problems relating to jet and surface condensers. Principle

of the condenser. Action of single and double acting air pumps. Hot-well. Measurement of condensation ; vacuum gange. Ditferent forms of condenser-barometers.

CHAPTER III.

Theory and description of engines.

Fixed and variable cut-offs ; their use, advantages, and inconveniences.
Theory and action of compound engines.
Theory of slide-valves; lap; angles of lap and lead; relations between the movement

of the slide-valve and that of piston ; steam and exhaust lead ; fixed cut-off; compression. Theory of variable cut-off's. Reversement of motion; different methods

of producing it. Classification of marine engines, according to the method of using the steam, the

mode of transmission of movement of piston to shaft, and according to the kind of

propeller. Advantages and disadvantages of the different kinds of engines. Necessity of a number of cylinders ; equalization of movement. Description and working of an oscillating engine; of a back-acting engine, ordinary

and compound; of a trunk-engine. Brotherhood's engine. Principal types of hoist

ing machines. Properties and use of metals and other substances employed in the construction of en

gines. Description of slide-valves; locomotive and double-ported slide-valves; box-valves;

D and piston valves, long and short. Fitting slide-valves in oscillating engines. Principal starting-gear; Stephenson's link; system of Creusot; systems of Mazeline

and of Dupuy de Lôme; systems of oscillating engines. Description of the principal systems of variable cut-off. Principal systems of throttle-valves of marine engines. Action and description of the different kinds of surface-condenser and of distilling

apparatus. Bed-frame, foundation-plates, fraining and flooring of engines. Lubricators. The screw and its elements. Advance and slip. Different types of screws. Various

arrangements for carrying the screw and screw-shaft. Fitting the screw upon the shaft. Description of a line of shafting. Stern stuffing-box and thrust-bearing.

Paddle-wheels and their parts; different systems. Advance and slip. Classification of marine boilers in relation to their pressure, their interior arrange

ment, and their shape. Complete description of a rectangular tubular boiler. Description of a cylindical tubular boiler of the authorized pattern. Detailed descrip

tion of a Belleville generator. Complete system of pipes of a system of boilers. Plates used in the construction of boilers; their assemblage. Furnaces, ash-pits, fire

bars, bridge walls, combustion-chambers, and smoke-boxes. Metal fortubes. Fixing of stationary or movable tubes in the tube-plate. Bracing, diagonal stays;

their necessity; their disposition. Bridge-bracing. Different systems of chimneys and their jackets. Steam communication ; stop-valves.

Dryers and superheaters. Safety-valves, and their working and weights. Escapepipes; water-gauges, gange-cocks; man-holes, mud-holes, and other accessories of boilers. Cocks. Pipes in general. Testing of marine boilers. Feeding of boilers; feed pumps and valves. Bilge-pumps, principal types. Giffard's injector. Eject

ors. Auxiliary feeding-engines or donkey-engines. Behrens's system. Principle of serro-moteurs : various types.

CHAPTER IV.

Management of engines. Properties of combustibles. Quantity of combustible necessary to evaporate a certain

weight of water. Combustibles used in the navy. Wood and different kinds of coal. Occasions for wetting the coal. Arrangement of fuel on the fire-grate. Thickness of the layer. Lighting. Treatment of fires while under way. Manner of stoking. Forcing and easing the fires. Banking tires. Arrangements for heating with wood. Care to be

given to chimneys and their stays. Fire in the chimney. Cleaning furnaces and grate-bars. Removing ashes and clinkers. Sweeping the

tubes while under way. Hauling fires. Preventing the entry of cold air. Filling up the boilers. Keeping up a constant water level. Precautions to be taken

relative to feeding, while in motion ; before and during a stoppage. Details of Belleville's generator. Dangerous lowering of the level of water in the boilers, and

the measures to be taken. Salts in solution in sea-water. Concentration and saturation. Salinometer; its con

struction and graduation. Saline deposits in boilers; means of prevention. Blowing out the boiler; precautions.

Continuous blowing off. Estimating the quantity to be blown off. Heat lost by

blowing off. Fatty deposits in the boilers. Apparatus for the removal of fatty substances from

feed-water. Saponification of fats. Various causes of the augmentation and diminution of pressure in boilers. Keeping

up, increasing, and reducing the pressure. Depression below atmospheric pressure. Disnse of a boiler at sea. Precautions to prevent its collapsing. Starting fires in a

fresh boiler. Case when the two preceding operations are done simultaneously. Care to be given to boilers after the fires are out. Manner of emptying them.

Modification of the number of boilers used in passing from one speed to another. Causes of foaming and of priming. Means of prevention. Leaks in the boiler and piping. Consequence of leaks in connection with feeding

and blowing out. Blowing through and turning over. Starting: precautions to be taken. Different

cases where the engine does not work. Accelerating or slackening speed; case where the partial closing of the steam-valve is

preferable to varying the cut-off. Stopping. Reversing. Adjustment of moving parts; Inbrication. Various noises. Thumping. Heating.

Binding,

Leaks in the engine; means of discovery and remedy.
Choking up of condensers and obstrnctions to injection water. Particular care in

the management of surface condensers.
General precantions to be taken in regard to the apparatus while in motion, before and

after arrival, before, during, and after engagement. Distribution of the personnel for getting under way, mooring, while under way, and during action. Method of utilizing the machinery in case of fire or springing a leak.

CHAPTER V.

Care and repair of engines.

Care to be taken for the maintenance and preservation of boilers and tubing; removal

of saline deposits; different processes in use. Preservation of the machinery and propeller during long periods of disuse. Description and use of the diving apparatus. Measures to be taken in case of an accident to the engine or boilers. Approximate

calculation of the number of cubic meters of steam, at atmospheric pressure, that can escape from a given boiler in case of explosion or rupture. Injury to cylinders, their heads, and stuffing-boxes. Provision for continuing work when a cylinder is disabled, particularly in compound engines. Injuries to the steam-piston and piston-rod; to valves; to valve-motion and eccentrics; to pipes and steam-valves; to the condensers and injection apparatus, particularly in surface condensers; to air pumps, their bonnets, piston-rods, valves and guards; to the hot-well and discharge pipes; to the cross-heads and keys, connecting-rods, link-work, and gearing; to the shaft, propeller, and cranks; to the foundation plates and framing, their straining in beavy weather; injuries to bearings, their caps and brasses; to the screw, the bearings, and the stern stufting-box; to the paddle-wheels and their floats; to the boilers—burnings, cracks, collapsing. Replacing of a rivet, a staybolt, or a plate. Bursting of tubes; plugging or replacing them. Broken gaugeglasses. Damaged pressure-gauges.

Accidents in the smoke-stacks. Accidents peculiar to the Belleville generator. Accidents to the pipes, cocks, and valves of the boiler; to the blowing-out and feeding

apparatus; to the bilge and donkey pumps. Rupture and explosion of boilers; their immediate causes; precautions to be taken. Inflammable mixtures in the flues and coal-bunkers. Spontaneous combustion of coal in the bunkers; measures to be taken.

CHAPTER VI.

Erection of engines.

Putting in place all the stationary parts of a screw-engine with direct-acting connect

ivg-rod, a back-acting engine, or a trunk engine (at the option of the candidate), and fixing the engine in the ship. Putting in place all the movable parts of one of the above engines; complete verification of the erection of one of the above engines, and specially of the line of shafting. Putting in place the fixed parts of an oscillating engine, and the fixing of this engine in the ship. Putting in place all the movable parts of an oscillating engine. Complete verification of the erection of this engine. Lining up the intermediate and paddle shafts. Lining up crank and pro

peller. Putting the boilers ou board. Their erection npon the keelsons, with or without floor

ing. Serro-moteurs.

CHAPTER VII.

Regulation of the work of engines.

Regulation in general of the valves and variable expansion gear; relative adjustment

of the valves of a compound engine. Rectification of the point of attachment of the

valve-stem and of the variable cut-off; also tbat of the position of the eccentrics. Theory of distribution and expansion valve diagrams. Showing by means of curves

the motion of the slide-valve. Use of this diagram. Erection and verification of

distribution and expansion valves by means of the regulation diagrams. Description and use of the indicator. Indicator connections of the different types of

engines. Atmospheric line; precautions to take to trace it. Tracing and analysis

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