Chapter XV: Introduction: Object of the work. Data of the Question (1)

A. PROJECTILE.

_First Section.--Substance, Forms, and Dimensions._

1. Choice of the metal employed in the manufacture of this projectile.

2. Forms of the projectile.

3. Internal diameter.

4. External diameter.

5. Dimensions of the vent.

6. Diameters of the high and low gauges.

7. Densities of the projectile empty and filled with powder.

8. Weight of the cast-iron ball of the same calibre as the howitzer shell.

_Second Section.--Minimum Bursting Charge._

9. Theoretical bursting charge for the hollow sphere.

10. Effect of the shock of the gases, and of their loss through the vent.

11. Résumé of the results arrived at in this chapter.

B. ORDNANCE.

_First Section.--Metal, Calibre, and Length of Bore._

12. Choice of the metal of which the piece is to be formed.

13. Windage of the projectile and diameter of the bore.

14. Effect of the windage on the velocity of the projectile.

15. Length of the bore and charge of powder which satisfy the data of the programme.

16. Résumé of the results arrived at in this section.

_Second Section.--Thickness of Metal necessary in order that the Piece may resist the Expansion of the Gases._

17. Explanation of the method employed to resolve the question of the thicknesses of metal.

18. First propulsion of the projectile, mean density of the gases after this propulsion.

19. Second propulsion of the projectile, mean density of the gases after this propulsion.

20. Third, fourth, &c., propulsions of the projectile, mean density of the gases after each of them.

21. Density and position of the strata (of gas) at the moment of the maximum of mean density.

22. Density of the last stratum for the positions which come after that of the maximum of mean density.

23. Tensions which result from the densities found.

24. Corresponding thicknesses of metal.

25. Résumé of the results obtained.

_Third Section.--Profile of the Piece._

26. Inclosing curve, resulting from the calculations of the second section.

27. Modification rendered necessary by the form of the posterior part of the projectile.

28. Utility of the chamber and its dimensions.

29. Tracing of the chamber and of its junction with the bore.

30. Thickness of metal around the chamber.

31. Chase and reinforce.

32. Determination of the angle of sight.

33. Vent and base ring.

34. Minimum weight of the piece for the resistance of the carriage.

35. Approximate calculation of the weight given by the profile previously obtained. Modification of this profile, if there is any.

_Fourth Section.--Trunnions, Breech, and Handles._

36. Dimensions of the trunnions and of the shoulders.

37. Tracing of the breech.

38. Base rings and other moldings.

39. Object and fixing of the preponderance of the breech.

40. Exact settlement of the position of the trunnions, definitive length of the reinforce.

41. Center of gravity of the piece; dimensions and position of the handles.

42. Means of executing the calculations indicated in the two preceding articles.

43. Table of the dimensions of the piece.

C. FIRE OF THE HOWITZER. EFFECTS OF THE PROJECTILE.

_First Section.--Elements of the Charging of a Howitzer._

44. Tracing of the shot bottom.

45. Tracing of the fuse.

46. Diameter of the cartridge (or of the bag.)

47. Charge of powder for firing with ball.

_Second Section.--Laws of the Motion of the Projectile. Establishment of Practice Tables._

48. Preliminary calculations.

49. Trajectory.

50. Curve of the inclinations.

51. Curve of the remaining velocities.

52. Curve of the durations of the passage.

53. Determination of the elevations for the fire at different distances.

54. Angle of fire, corresponding to the different distances of the object aimed at.

55. Angles of descent.

56. Résumé of the laws of the motion and of the practice tables.

_Third Section.--Effects of the Projectile._

57. Depth of penetration in the media indicated by the programme.

58. Effects of explosion in earth.

59. Résumé of the results relating to the effects of the projectile.

NOTE.--The formulas cited in the memoir need not be accompanied by their demonstration, except in the case of the latter not having been already developed in the lessons of the artillery course. It will be sufficient to insert in this notice only the final result of the calculation relating to each formula, without entering into the details of such calculations.

The study of the design for ordnance is preceded by four lessons intended to make the students acquainted with all the details of its execution, and the substance of which is indicated in the programme of the memoir.

III. APPLICATION OF THE THEORIES OF THE ARTILLERY COURSE (6 DAYS.)

This study is intended to apply to the students those theories of the course which have not found their application in the design for ordnance. It comprises the solution by arithmetical calculations of certain questions on the effects of powder, the balistic pendulum, the effects of recoil, the science of projectiles, the draught of carriages, &c. The number of the questions may vary according to their nature and the time which their solution requires. The stating of the questions and the results of the calculations are inscribed on separate papers. This study is preceded by a lesson in which the students have recalled to them the formulas which they have to employ.

IV. DRAWING OF ARTILLERY MATERIAL (26 DAYS.)

The drawing of artillery material has for its object the representation by figured sketches of a gun-carriage, carriage, or other furniture of artillery material. The sketches, on paper put together in the form of a book, and headed by a special programme for the object to be drawn, consist of plans, sections, or elevations of the object, executed on certain scales, and of detailed projections of the principal iron-work and joints. The whole fixed by the special programme in question.

All the simultaneous projections of any one part of the object drawn (fore part or hind part for carriages) must be completely figured; they are accompanied by explanatory inscriptions, with letters of reference to show the names of the pieces in wood or metal which they comprise.

Each collection of sketches must contain as well a notice in confirmation of the drawing, giving the complete description and the properties of the object to which it refers.

The students make two surveys of the same kind; eight days are allowed for each of these surveys, including the composition of the confirmatory notice.

The first survey is followed by the execution of an unfigured drawing, containing a complete representation of the object surveyed (elevation and plan,) obtained by the combination of the partial projections contained in the sketch. The drawing should be colored in the conventional uniform tints, and accompanied by an explanatory inscription, with letters of reference. Ten days are devoted to this work of composition.

V. TRACING OF BATTERIES (4 DAYS.)

This work consists in executing sketches showing, each in accordance with a separate programme, the complete plan of a battery and the essential data having reference to its construction and to its armament. The sketches, made by scale and completely figured, must comprise in the case of each battery to be represented--

1. The general plan of the battery, on the scale of 1/200.

2. The sections or elevations necessary for the understanding of this plan, including the detail of the powder magazines, lines of communication, &c., on the scale of 1/100.

3. An inscription giving the object of the battery, its armament, its general arrangement (_terre-plein_, embrasures, revetment, communications, magazines, &c.,) the workmen, materials, and tools necessary for its construction, and finally the duration of the labor and its distribution by day and night.

Four days are devoted to this work, which must be executed on a half sheet of colombier paper. The separate programmes relating to each of these batteries are shown on the study orders of the rooms.

RECAPITULATIVE TABLE.--ARTILLERY STUDENTS.

[KEY]
NL Number of the Lectures.
CG Credits given for the Lectures.
+A With application at 1h 50m.
-A Without application at 3h.
TC Total Credits.
Q Number of the Questions.

---------------------------------+----+------------+--------+----
LECTURES | | CG | |
| +-------+----+ |
| NL | +A | -A | TC | Q
---------------------------------+----+-------+----+--------+----
Division of the Course-- | | | | |
First Part. Theory, | | | | |
Sections 1, 2, 3, | 26 | 18 | 42 | 60 | 4
Second Part. Description of the | | | | |
Material, Sections | | | | |
1, 2, 3, 4, 5, 6, | 20 | 30 | .. | 30 | 3
Third Part. Fire of Ordnance, | 4 | .. | 12 | 12 | 1
Fourth Part. Construction | | | | |
of Batteries, | 6 | 9 | .. | 9 | 2
Fifth Part. Organization and | | | | |
Service of the Artillery, | | | | |
Sections 1, 2, 3, | 8 | .. | 24 | 24 | 1
Sham Siege, | 2 | 3 | .. | 3 | ..
Lectures in preparation | | | | |
for the Studies, | 9 | 13 50 | .. | 13 50 | ..
+----+-------+----+--------+----
Totals, | 75 | 73 50 | 78 | 151 50 | 10
---------------------------------+----+-------+----+--------+----

[KEY]
S Sketches
D Drawings.
M Memoirs.
Inv Inventories.
ID In-door Attendance. 1½ hours.
OD Out-door Attendance. 1½ hours.
C Credits in round Numbers.

---------------------------+-----------------------------------
STUDIES. | Number of
+----+----+----+----+----+----+-----
| S | D | M | Inv| ID | OD | C
---------------------------+----+----+----+----+----+----+-----
Survey of Ordnance, | 1 | .. | .. | .. | .. | 1 | 5
Tracing of Ordnance, | .. | 1 | .. | .. | 11 | .. | 50
Design for Ordnance-- | | | | | | |
Calculations, | .. | .. | .. | 1 | 10 | .. | 45
Drawings, | .. | 1 | .. | .. | 8 | .. | 35
Memoir, | .. | .. | 1 | .. | 6 | .. | 55*
Application of Theories-- | | | | | | |
(Artillery Question) | .. | .. | 1 | .. | 6 | .. | 55†
First Survey of Material-- | | | | | | |
Sketch, | 1 | .. | .. | .. | .. | 8 | 35
Composition of Notice, | .. | 1 | .. | .. | 10 | .. | 45
Second Survey-- | | | | | | |
Sketch, | 1 | .. | .. | .. | .. | 8 | 35
Sketch of Batteries, | 1 | .. | .. | .. | 4 | .. | 20
+----+----+----+----+----+----+-----
Totals, | 4 | 3 | 2 | 1 | 55 | 17 | ..
---------------------------+----+----+----+----+----+----+-----

[* The time is doubled for the memoirs.]

[† Ditto.]

RECAPITULATION.

Lectures, 150}
Studies, 380} 530

RECAPITULATIVE TABLE.--ENGINEER STUDENTS.

[KEY]
Cr Credits given for the Lectures.
L Number of the Lectures.
+A With application at 1h 50m.
-A Without application at 3h.
T Total Credits.
Q Number of the Questions.
---------------------------------+----+----------+--------+----
LECTURES | | Cr | |
| +-----+----+ |
| L | A | -A | T | Q
---------------------------------+----+-----+----+--------+----
Division of the Course-- | | | | |
| | | | |
First Part. Theories, | | | | |
Sections 1, 2, 3, | 24 | ... | 72 | 72 | 4
Second Part. Description | | | | |
of the Material, | | | | |
Sections 1, 2, 3, 4, 5, 6, | 14 | ... | 42 | 42 | 2
Third Part. Fire of Ordnance, | 4 | ... | 12 | 12 | 1
Fourth Part. Construction | | | | |
of Batteries, | 6 | 9 | .. | 9 | 1
Fifth Part. Organization | | | | |
and Service of the | | | | |
Artillery, Sections 1, 2, 3, | 8 | ... | 24 | 24 | 1
Mock Siege, | 2 | 3 | .. | 3 | ..
+----+-----+----+--------+----
Totals, | 58 | 12 |150 | 162 | 9
---------------------------------+----+-----+----+--------+----

------------------------+------------------------+--------+
| Number of | |
+-----------+------------+ |
STUDIES | Sketches. | In-door | Credit |
| | Attendance | |
------------------------+-----------+------------+--------+
Sketches of Batteries, | 1 | 4 | 20 |
------------------------+-----------+------------+--------+

RECAPITULATION

Lectures, 162 }
Studies, 20 } 182. Round number, 180.

IV. PROGRAMME OF THE COURSE OF MILITARY ART AND FIELD FORTIFICATION.

The course is divided into six parts, and is made up of lectures and works of Application in the Halls of Study and on the ground.

I. LECTURES.

The 1st part contains sundry historical notices on the
Organization of Armies, 6 Lectures.
2d part is on Tactics, 3 “
3d “ Castrametation, 2 “
4th “ Field Fortification, 16 “
5th “ Military Communication, 10 “
6th “ Strategy, 6 “
----
Total 43

FIRST PART.--HISTORICAL NOTICES ON THE ORGANIZATION OF ARMIES.

The first lecture commences with explanations relating to the Greek and Roman armies; their order of battle, mode of marching; comparison of the Roman Legion with the Greek Phalanx, and of the Roman Legion under Marius and under the Emperors.

2. Military organization of the Franks under the Kings of the first race. Consequences of the feudal system, acting on the military organization. Feudal armies. Chivalry. Crusades, and war against England. Establishment of the first standing armies. Results dependent on the introduction of fire-arms. Progress made in the Art of War and in the organization of armies, from the sixteenth century to the present time.

3. Necessity for standing armies. Their proper character. Recruiting. Promotion. Degrees of rank. Station of the officers. Various positions of military men. On the composition of armies, Infantry, Cavalry, Artillery, Engineers. _Corps d’Etat-Major._ Composition of the army during the Revolution and during the Empire. Actual formation of a French army.

General Staff. Commissariat. (_Intendance._)--Different services dependent on it.

Relations between the strength of each of the arms that make up an army. On other corps which are not classed among the principal arms.

4, 5, 6. Summary relating to the military organization of the principal Powers of Europe.

SECOND PART--ON TACTICS.

1. Definitions. Formations. Manœuvers; character of a good manœuver. Order of battle: first, of the Infantry; second, of Cavalry; third, of the Artillery; relating to Sharpshooters (_tirailleurs._)

2. Brief summary of the principal movements in battalion drill to pass from line to the order in columns and reciprocally. Movements in column. Movements in battle. Dispositions to be made against Cavalry.

3. Of the principal movements in line. Order of battle. Line of battle. Formation of Infantry to advance against the enemy. Action of Cavalry. Principal formations. Charges of Artillery. Use of the Three Arms.

THIRD PART.--CASTRAMETATION.

1. General principles of castrametation. Situation. Construction and disposition of barracks. Camp of a Regiment of Infantry, of Cavalry, and of a Battery of Artillery.

2. Manner of tracing a camp on the ground. Huts; details relating to their construction. Tents. Bivouacs. Screens. Kitchens and camp ovens. Choice of the site of a camp; precautions to be taken for its security. Main guards. Advanced posts. Patrols and sentinels.

FOURTH PART.--FIELD FORTIFICATION.

1. Definition of fortification in general. Object and character of field fortification; its utility demonstrated by historical examples. Napoleon’s opinion. Essential principle of field fortification. Discussion on the ordinary profile of earthen entrenchments; on the dimensions to be given to the ditch in level ground.

2. Definitions relating to the trace; general principles. Redoubts.

3. On the elements of lines. Relation that should exist between the crest and the internal size of a closed work. Maximum and minimum of the sides of a square redoubt. Defects inherent to the trace of this kind of redoubt. Circular redoubts. Redoubts _en crémaillères_. Star forts. Lines with bastions.

4. Revetments of various kinds; case in which the slope of the ditch should be reveted; choice to be made of the different kinds of revetments.

5. Exterior dispositions; accessories to the defense; abattis; _trous de loups_; palisades; _chevaux de frise_, &c. Precautions to be adopted with reference to such accessories.

6. Interior dispositions; armament of musketry, artillery, barbettes, and embrasures; their advantages and disadvantages; construction of.

7. Powder magazines of different kinds. Small earthen entrenchments; palisades, carpentry, or blockhouses; advantages and disadvantages of blockhouses. African blockhouse. Closing of field-works.

8. Artificial inundations; under what circumstances they can be considered as obstacles. Positions and dimensions of dikes. Details of their execution; what advantage can be drawn from an inundation having less than five feet depth of water.

9. What is understood by the defilading of a work. The defilading of fieldworks should, above all things, be made to depend on their trace and situation. Definitions: dangerous ground; dangerous points. Defilement of an isolated and closed work; in what case it is practicable. Use of traverses. A partial defilement may sometimes be sufficient.

10. Continuous lines. Broken lines. Traces of redan, tenailles, cromailleres. Bastioned lines. Comparison between continuous and broken lines. Principal objections to their use. Utility of each demonstrated under certain circumstances.

11. Lines in broken ground: their form should depend on the nature of the ground. On the manner of fortifying a table-land. Expedients for defilading portions of lines. On the manner of making use of the natural obstacles of the ground; forests, scarps, marshes, water-courses, &c. Method of fortifying a house, village, an open town. Defense of a bridge or road.

12. _Têtes de pont_. Utility of small earthen entrenchments in these cases to facilitate the passage of a retreating army. Traces of a large _tête de pont_. Principal circumstances relating to the use of lines in war. Lines of circumvallation and countervallation. Frontier lines. Retrenchments against a descent. Lines that an army should make in an enemy’s country, far from its base of operations. Entrenchment on the field of battle. Lines, mixed, proposed by General Rogniat.

13. Attack and defense of entrenchments, of a continuous line; of a line at intervals; of an isolated work, &c. Examples of the attack and defense of lines.

14. Instruction relating to the operations for profiling and defilading on the ground.

15. Instruction on the project of field fortification. Calculation of the dimensions of a ditch corresponding to the face of a work of a variable relief, and to be constructed in level or other ground. Details relating to traverses, small entrenchments; defensive caponnieres, and accessories to defense, &c.

16. On the construction of entrenchments. Practical operations and organization of workshops to obtain durable and solid work. Necessity, in most cases, for accelerating the construction of entrenchments. Vauban’s precepts. In what manner the work must proceed to obtain a useful result; and, in the event of plenty of hands, how to finish it promptly.

FIFTH PART.--ON MILITARY COMMUNICATIONS.

1. On roads. 1 and 2, Classification of roads. Section and trace of roads in level and mountain country. Details connected with the study of a project for a road. Particular conditions relating to military roads. Execution of paved and macadamized roads. Roads for passing difficult places by the use of fascines, logs, &c. Maintenance and destruction of roads.

2. On military bridges.

3. Observations on the currents and change of form in the bed of rivers. Fords. Transverse sections, &c. Reconnaissances of rivers. Properties essential to military bridges. Relation between the buoyancy and the load in the case of floating supports. Anchorage. Construction of the abutments. Means of rendering bridges stable.

4. Construction of a bridge of boats in different ways. Bridges made of ordinary boats. Method of withdrawing a bridge of boats.

5. Raft bridge. Relation between the weight and the extrinsic load of a raft. Number of trunks of trees required for a raft bridge on a river of given dimensions. Weight of the trunk of a tree. Number and space between rafts. Construction of a raft and a bridge of rafts. Bridges of casks and trestles.

6. Rope bridges; their use. Calculations respecting the tension and diameters of ropes. Construction of a suspension bridge, and calculations relating to it.

7. Bridges on piles, carriages, gabions, &c.

8. Measures to be taken for the preservation of military bridges. Destruction of military bridges; also of masonry bridges. Reëstablishment of bridges.

9. Flying bridges. Ferry-boats, tubs, passage by fords, on the ice, by swimming.

10. Execution of the passage of rivers. Advancing and in retreating. Examples.

SIXTH PART.--STRATEGY.

1. Definition. Fundamental principles of all operations in war. In all cases there are--first, the base of operations; second, the point to be arrived at; third, the line of operations. Strategetical points and lines.

2. On marching. Preparatory and manœuvering marches. Advanced and rear guard. On provisions. System of magazines. Requisitions. Invasions. Battle. Examples.

3. On positions. War in a mountainous district. Retreats. Pursuit. Convoys. Partizans.

4. Winter quarters. Cantonments. War against irregular bands. Military reconnaissances.

5. Precis of the campaigns of the French armies.

6. Analysis of the principal campaigns of great captains.

II. PROGRAMME OF THE WORKS OF APPLICATION EXECUTED IN THE HALLS OF STUDY.

These works consist of four Plates of Drawings, two Memoirs, and a Project, of Field Fortification. Of the four Plates of Drawings, two relate to Field Fortification, and two, accompanied by Memoirs, relate to Military Communications.

Plate 1--Elements of lines. Tracing, on the scale of 1/1000 of the interior crest (only) of a redan, lunette, redoubt, star fort, bastioned fort, according to particular data given to each Sous-Lieutenant. Construction on the scale of 1/200 of a complete profile for each of these works, supposed to be established on level ground. Complete calculation of the deblais and remblais for one of the preceding works, according to the instructions of the Professor.

Plate 2.--Details of a field-work. Trace on the scale of 1/200 of a portion of the work of which the deblais and remblais has been calculated. Graphic construction of a barbette and of a direct or oblique embrasure. Details of revetments in fascines, hurdles, turf. Pisé. Drawing of a blockhouse.

Plate 3.--Accompanied by a Memoir. Project of a portion of road on ground represented by certain lines, according to certain data.

Plate 4.--Accompanied by a Memoir. Military bridges.

1. Drawing of a portion of a bridge of boats, three openings being shown; the two first relating to the successive construction of the bridge, and the third, of the construction by portions.

2. Project for establishing a raft bridge; the width of the river; the kind of troops to pass over the bridge; the length; mean diameter of the available trunks of trees and the length and scantling of the joints being given. The drawing to exhibit a plan of two openings of the bridge, and a transverse section.

3. Tressel bridge. To draw a longitudinal elevation and a transverse section of a tressel bridge, being given the length of the top and of the feet of the tressels up and down the stream.

4. Project for the repair of a broken arch; being given the opening of the head, the elevation of the roadway of the bridge above the level of the water; the depth of the water, the rapidity of the current, the kind of troops to pass over the bridge, and the available time and the resources as regards men and materials which can be had recourse to.

_Programme of the Project of Field Fortification._

This project is made by the Sub-Lieutenants, according to certain data given to each of them. It has for its object to cause them to study:--1st. The trace. 2d. The complete organization necessary for its defense. 3d. The details of construction of a field-work. In consequence, the work comprises three Plates of Drawings and a Memoir divided into three parts.

_Programme of the Drawings._

Plate 1.--Plan of the whole. This plate has for its object the research of a trace and of a combination of suitable works for the fortification of a certain portion of ground under certain circumstances of war defined by particular data. Each Sub-Lieutenant receives a lithographed sheet representing the ground to be fortified, and he has to exhibit on this sheet the works he proposes, in tracing in plain lines the horizontal projections of the interior crests and superior limits of the ditch, and in dotted lines the stockades or palisades; to show in black figures at the angles of the works the relief of the interior crests; the sites of barbettes, embrasures, traverses, barriers, &c., being indicated by reference letters and explanatory notes, the lines in red showing the directions and objects of the line of fire.

Plate 2.--Organization of a work.

This plate has for its object the study of the details of the interior and exterior organization of a work of a certain form, in order to render it susceptible of making a good defense.

Each Sub-Lieutenant will draw a complete plan of such one of the works shown on Plate 1, as may be pointed out by the Professor. He will represent the ditches, parapets, embrasures, accessory defenses, small entrenchments, descents into the ditch, &c., according to the particular data furnished to him; the figures of the relief of the crests of all kinds, the deblais and remblais being marked at all the angles. The figures of the natural ground will be underlined. The same plate will contain figured profiles which have served for the determination of the complete projection of the work. Scale 1/250.

Plate 3.--Details of construction.

The object of this plate is to show the composition of workshops and the manner that should be adopted in the construction of field-works, according to circumstances, for the execution of the deblais and remblais.

Each Sub-Lieutenant will indicate the manner in which the work drawn on Plate 2 should be constructed:--1st. To render it durable and solid. 2d. To arrive rapidly at a useful result, even with limited resources of workmen and tools. 3d. To finish the work in the shortest possible time, by making use of all the necessary means. A plan will show the composition of the workshops under each of these hypotheses, and the successive advancement of the work will be represented by certain profiles supposed to be made at certain periods of the construction through the center of one of the faces of the work. In these profiles a firm trace, figured with altitudes, will show the limits of the deblais and remblais at the period represented by the profiles; and in addition by dotted lines, the final results proposed to be obtained. All these projects must be accompanied by a figured plan, showing the principal altitudes in meters. The remblais will be colored with gamboge, the undisturbed earth in bistre, and the deblais will be left white.

_Programme of the Memoir._

Each Sub-Lieutenant will write at the head of his Memoir the text of the particular programme, to which he is obliged to conform in the preparation of his project, and he should add to the text of the Memoir all the sketches properly figured, which are necessary for the proper appreciation of the dispositions which are not sufficiently detailed on the Drawings.

The Memoir is divided into three parts, corresponding to the three Plates of Drawings.

FIRST PART.--CONSIDERATIONS RESPECTING THE WHOLE PROJECT.

1st. General principles, according to which it would be proper to trace the works indicated in the particular programme, such as lines at intervals, continuous lines, têtes de pont, &c.

2d. Description of the tracing in Plate 1. Reasons deduced from the form of the ground or the nature of the military operations that led to the adoption of the trace. Object of the works, and their connection with each other.

3d. Number, description, and position of the pieces of artillery composing the armament.

4th. Maximum and minimum of troops that could be employed in the defense of these works.

5th. Dispositions which should be adopted (relatively to the necessary preparations in materials and to the separation and movement of troops) for the attack and for the defense.

SECOND PART.--COMPLETE ORGANIZATION OF A WORK.

1st. Particular object of the work shown in Plate 2. Trace of the complete projections of the parapets, barbettes, ramps, embrasures, traverses, &c.

2d. Conditions that should be fulfilled by the ditch. Approximate calculation of dimensions which should be given to it, taking into account the increased means of providing for an excess or defect of the deblais.

3d. Discussion on the site and the part which might be expected from small entrenchments, accessory defenses, shutters, descents of ditches, &c.

4th. Site of powder magazines; capacity that should be given to them, suitable to the state of the munitions necessary for the armament of the work.

THIRD PART.--DETAILS OF CONSTRUCTIONS.

1st. Means of ascertaining the nature of the earth; considerations respecting relays for the transport of earth with the shovel.

2d. Description, number and disposition of the workmen in a shed for deblai and remblai, according to the nature of the ground and number of relays.

3d. Explanation of Plate 3. Organization of the sheds and conduct of the work where the duration and solidity of the work are the greatest essentials; where, on the other hand, rapidity of execution is the principal thing to be fulfilled.

4th. Which of the modes of construction exhibited in Plate 3 it would be desirable to employ for the proposed works, according to the circumstance specified in the particular programme. Calculation for this mode of construction, of the time and of the numbers of men and tools necessary for the execution of the deblais and remblais of the work given in the plate.

5th. Details of construction of the revetments, magazines, shutters, accessory defenses, artillery platforms, &c.

III. PROGRAMME OF EXTERIOR WORKS.

These works consist of an exercise in tracing out a camp, and an exercise on the profiling and defilement of field-works.

The exercise on tracing camps has no particular programme, but is preceded by a lecture given by the Professor.

_Programme of Practical Exercises on the Defilement and Profiling of Field Works._

This exercise comprehends: 1st, work on the ground; 2d, a Memoir.

The work on the ground has for its object: 1st, the trace of the projections of the interior crest of a work, whose position and form are known; 2d, the determination of the relief of the interior crest; 3d, the profiling of the different parts, so that the relief of the different parts of the parapet, barbettes, traverses, &c., may all be fixed.

The Sub-Lieutenants for this kind of work are divided into groups of six or eight, employed together on the same work, each group being divided into two squads. The work may be a lunette or a redan of given dimensions, having a parapet of three meters thick, and a natural slope of one to one.

1st. The direction of the capital will be marked out in front by two numbered pickets.

2d. The tracing will be executed by means of poles or pickets placed at all the angles, and at the extremities of the gorge; the relief will be determined by the practical methods of defilement adverted to in the lecture which preceded the work.

3d. The relief obtained by the defilement will be marked on all the poles or pickets placed at the angles, and at the extremities of the sides of the work.

4th. On each face two vertical profiles will be executed, perpendicular to the horizontal projections of its interior crest. In order that these profiles shall not interfere with those placed at the angles, they must be established at several meters distant from the extremity of each face.

5th. The profiles of the angles will be deducted by simple prolongations, and the same for the profiles of the gorge. If the homologous crests of two contiguous faces do not meet each other, they should be reconciled by joining two points taken on each of them at half a meter from the intersection of their projections.

6th. On the traverse, designed to secure the defenders from a reverse fire, two profiles are constructed, near to its extremities if its crest is a right line, but if it is bent, another profile must be set up at the junction.

7th. The data of all these profiles are, the relief of the interior crest at the point where it is encountered by the profile, the thickness of the parapet, the constant parts of every profile, and the natural slope of the ground; the portion of the slope of the traverses exposed to the view of the dominant heights should not be reveted, the others should be.

8th. At the points of intersection of the profiles with the projections of the ridges of the works, as well as at the points used for adjusting, poles or pickets are placed, on which the points belonging to the ridges are marked. These points will be joined together in each profile by twine, indicating the different planes of the work.

9th. The form and dimensions of the batteries, either of barbettes or embrasures, will be equally determined by poles or pickets placed at all their angles, and united together by twine in the manner that will be subsequently explained.

10th. For the barbette batteries, the first thing to be done is to establish and to construct the front coupé of the salient of the interior crest, and substitute an interior horizontal crest throughout the extent of the barbette for that situated in the plane of defilement. The necessary adjustments are then made between the slope of the parapet of the barbette and that of the rest of the face, and indicate by means of twine the intersections of the terre-plein of the barbette and of its slope with the different planes of the work.

11th. For the embrasures, after having determined their direction, the intersections of the cheeks and bottom, with the interior and exterior slope of the parapet, and with its slope; also the slope which terminates the interruption of the banquette throughout the extent of the battery. In the case where the platform is formed more than 0^m 4 elevated above the soil, a ramp is constructed with its slope, and the intersections with the slope from the platform are shown.

12th. After the batteries, the slope of the ends of the traverses and of the passages for entry and exit are constructed.

13th. The traverse will be finished by adjusting its different planes with those of the parapet. In the particular case, where it was interfered with to make a passage over the banquette, it is finished by reveting the slope passing by the crest of the banquette of the work.

14th. At the passages of entry and exit from the work, the parapets will be finished by the slope of the revetment, whose intersections with the different planes of the parapets must be determined.

15th. For each squad of workmen, the distance of the salient of the work to the point on which it will be defiladed must be determined.

MEMOIR.

1st. Object of defilement--which is considered to be dangerous ground, dangerous point, plane of defilement.

2d. Position of the dangerous point relatively to the work which is to be defiladed. Practical method on the ground. Results to which it leads.

3d. On the field this method is not always applicable to an isolated work, and never is so to entrenchments of a great development, such as lines, large têtes-de-pont, &c. By what proceeding is it generally expedient to attempt to fulfill in war the indisputable condition of defilement.

RECAPITULATION FOR THE SUB-LIEUTENANTS OF ARTILLERY AND ENGINEERS.

[KEY]
NL Number of the Lectures.
+A With application.
-A Without application.
I No. of Interrogations.

---------------------------------+----+----------------------
First Lectures.-- | |Credits for Lectures.
| +----+----+-------+---
Parts of the Course. | NL | +A | -A | Total | I
---------------------------------+----+----+----+-------+---
1st Part. Historical notions | | | | |
on the Organization of Armies | 6 | | 18 | 18 }|
2nd Part. Tactics | 3 | | 9 | 9 }| 1
3rd “ Castrametation | 2 | | 6 | 6 }|
4th “ Field Fortification | 16 | 24 | | 24 | 2
5th “ Military Communications | 10 | 15 | | 15 | 1
6th “ Strategy | 6 | | 18 | 18 | 1
+----+----+----+-------+---
Totals | 43 39 51 90* 5
------------------------------------------------------------

[* The number 90 is applied to the interrogations and to the obligations of the notes.]

[KEY]
D Drawings
M Memoirs
I In the Halls
O Outside
C Credits

-------------------------------------+--------------------------
| Number of
+--+---+------------+------
EXECUTION OF WORK. |D | M |Attendances | C
| | +-----+------+
| | | I | O |
-------------------------------------+--+---+-----+------+------
Drawings of Military Art,-- | | | | |
Plate 1. Elements of Lines | 1|.. | 4 | .. | 20
Plate 2. Details of a Field-work | 1|.. | 8 | .. | 35
Plate 3. Project of a Road | 1|.. | 8 | .. | 35
Memoir |..| 1 | 2 | .. | 20
Plate 4. Military Bridges | 1|.. | 8 | .. | 35
Memoir |..| 1 | 2 | .. | 20
Project of Field Fortification,-- | | | | |
Plate 1. Plan of the whole | 1|.. | 3 | .. | 15
Plate 2. Organization of a work | 1|.. | 8 | .. | 35
Plate 3. Details of Construction | 1|.. | 5 | .. | 20
Memoir |..| 1 | .. | 3 | 30
Tracing of Camps |..|.. | .. | 1 | 5
Tracing on the Ground |..|.. | .. | 2 | 10
Memoir |..| 1 | 1 | .. | 10
+--+---+-----+------+------
Totals | 7| 4 | 51 | 3 | 280
-------------------------------------+--+---+-----+------+------

RECAPITULATION OF THE CREDITS OF INFLUENCE.

Lectures, 90
Execution of Work, 280
-----------------------
Totals 370

4th. Methods of defilement employed. Determination of the different planes of barbettes, of their ramps, of the profiles of the gorge, &c. Construction of embrasures.

5th. Means made use of in practice for determining the distance of the salient of the work to the dangerous point on which it is defiladed.

V.--PROGRAMME OF PERMANENT FORTIFICATION, AND THE ATTACK AND DEFENSE OF PLACES.

The course of instruction in Permanent Fortification and the Attack and Defense of Places, is divided into three parts, viz:--

[KEY]
Art. Artillery.
Eng. Engineers.

----------------------------------------------------+-------------
| No. of
| lectures to
+------+------
| Art. | Eng.
----------------------------------------------------+------+------
The first part consists of the study of the | |
Construction of existing Fortifications, | |
and it is common to the two services; | |
it comprises, | 10 | 10
The second part contains principles | |
of the Art of Fortification, divided into | |
three sections, of which the | |
{1st section relates to | |
Fortification on level ground | 19 | 19
{2nd section relates to | |
Fortification on hilly ground | 19 | 26
{3rd section relates to general | |
questions of Fortifications | 4 | 5
Third part relates to the Attack | |
and Defense of Places, | 24 | 24
+------+------
Total number of Lectures, | 76 | 84
----------------------------------------------------+------+------

The first part contains a description of the various works of permanent fortification, their respective uses, and the changes that have been successively made in them, together with a short history of ancient fortification prior to the invention of powder, and the changes introduced by the use of fire-arms.

The systems of Errard, Beville, Pagan, Vauban, Cochorn, and Cormontaigne.

The first section of the second part describes the principles on which the various parts of a front of fortification on level ground, and according to Cormontaigne’s system, are regulated, such as the command, relief, defilement, form, length, and material of which the various parts should be constructed; the modifications required by the absence or presence of water; the changes which are necessary as regards exterior or advanced works, and ending with a comparison of a front of fortification according to Cormontaigne, with a modification of the same system introduced by the French engineers.

The second section commences with the principles of defilement and its application under various given circumstances, proceeds with the description of an imaginary work founded on certain given data, and furnishes the data of its proposed construction. It then supplies the theory relating to mines, and their use in the attack, defense, and destruction of places, and points out the particular duties of engineers in fortified places, and the proper and most efficient manner of carrying them on.

The third section relates to the preparation of projects for the improvement of inefficiently fortified places, and to the utility, particular organization, and proper position of fortified places on a frontier line. It then explains the necessity for military law in providing for the security of fortified places and districts along the frontiers of a state.

The third part describes the various operations connected with the attack and defense of a bastioned fortification, commencing with the operations preliminary to the siege and investment of the place, and continuing to describe the several processes to be employed in the attack of the place, with the corresponding efforts that should be made during its defense, and ending with an historical account of certain sieges.

This course requires the practical completion of the following:

Nature of the Work; Time allowed for its completion.
Subject of the Work.
Scale

1st Part.--On existing fortifications.

Single Plate, 20 days,
Complete projection of the front of Cormontaigne without
counterguard or cavalier,
1/1000
Three profiles of the front,
1/500

2d Part.--Principles of the Art of Fortification.

Plate, No. 1, 8 “
1st Section: Fortifications on level ground.--Principal graphical
constructions of the front on level ground according to particular
data given to each Student
1/1000
Plate, No. 2, 28 “
Complete projection of the whole of the visible and underground
parts of the same front,
1/1000
Three profiles of the front,
1/500
Memoir, 6 “
Description of the principles of the Fortification, with a
detailed discussion of the dispositions adopted in the particular
case treated by the Students.
Plate 3, 20 “
2d Section: Fortification on hilly ground.--Drawing of the ideal
fortress and of its Tête-du-pont, with the interior entrenchments,
inundation, sluices, and all necessary details to enable a proper
comprehension to be had of the action of the water.
Drawing complete of one of the fronts of the place and its
outworks, described by a particular programme. Defilement of all
the works of this front and of the masonry of one of its faces,
1/5000
Memoir, 3 “
On the situation of the fortification; description of the
imaginary fortress, and of the management of the water;
explanation of the operations of defilement drawn on Plate 3.
Plate 4, (Artillerie.) 10 “
Plan and profile of a full revetment of the escarp with its
counterforts,
1/200
Plan, profiles, and elevation of a revetment “en décharge.”
1/200
Detail of a gallery and small chamber of a mine, of its tamping
and mode of firing,
1/50
Plate 4, (Engineers.) 20 “
Detailed project of one of the parts of the front of fortification
defiladed in Plate 3. Plans at different height; disposition of
the galleries and small chambers of mines required for blowing up
the whole of the ground between two listening galleries.
1/250
Plate 5, 10 “
Sections and elevations of the preceding project. Foundations,
coping of vaults, dressing of cut stones, &c.,
1/125
Detail of a small gallery and chamber of a mine, comprised in
the dispositions of Plate 4. Tamping and mode of firing.
Avant, 3 “
Abstractions of measurement of a part of the preceding project,
....
Plate 6, 11 “
Study of the alterations in the earth of the same part of the
projects, representing the four principal periods of the work,
by a plan and section, with an elevation of the 4th period,
1/250
Memoir, 2 “
General theory of the removal of earth. Application to a
particular project,
....
Register, 3 “
Register of the removal of earth as represented in Plate 6.
Estimate, 1 “
Estimate of the part of the project to which the abstraction of
measurements has been applied.
3d Section: Projection of the improvement of an existing
fortified place.
Plate 7, 30 “
Complete projection of the project for improving an existing
fortified place,
1/1000
Plate 8, 6 “
Details of the most interesting parts of the project, in plans,
sections, and elevations,
1/250
Memoir, 2 “
Marginal notes on the defects presented by the existing system,
and on the means employed for correcting them.
Calculation, 5 “
Balance of the “deblais” and “remblais” of the project.

3d Part.--Attack and Defense of Places.
Single Plate, 30 “
Project of attack of a front of fortification on level ground,
1/2000
Details of the attack,
Journal, 4 “
Journal of the siege. Details relating to the composition of
the garrison and of the besieging army; also on the material for
the Artillery and Engineers required for the attack and defense.
Pen sketch of the most elementary works of attack.
1/200

[Transcriber’s Note:
The “Observations” column is divided into four sections:
Through Plate 3: Common to Students of Both Services.
Plate 4: Artillery.
Plate 4 (Engineers), through end of 2nd Part:
Special to Engineer Students.
3d Part: Common.]

RECAPITULATION FOR THE ARTILLERY.

[KEY]
NL Number of Lectures.
Cr Credits for the Lectures.
+A With application (_a._)
-A Without application (_b._)
T Total.
I Number of Interrogations.

-------------------------------+----+-------------------+-----
I. LECTURES. | | Cr |
PARTS OF THE COURSE. | +------+------+-----+
| NL | +A | -A | T | I
-------------------------------+----+------+------+-----+-----
First Part. Study of | | | | |
existing Fortifications, | 10 | 4.5 | 21 | 26 | 1
Second Part. Principles | | | | |
of the Art of Fortification, |....| .... | .... | ....| ...
First Section. Fortification | | | | |
on level ground, | 19 | 24.0 | 9 | 33 | 2
Second Section. Fortification | | | | |
on hilly ground, | 19 | 19.5 | 18 | 38 | 2
Third Section. General | | | | |
questions of Fortification, | 4 | .... | 12 | 12 | ....
Third Part. Attack and | | | | |
Defence of Places, | 24 | 24 | 24 | 48 | 2
+----+------+------+-----+-----
Totals, | 76 | 72 | 84 | 157 | 7
-------------------------------+----+------+------+-----+-----

[(_a._) The lectures with application count for 1 hour 5 minutes.]

[(_b._) Those without application for 3 hours.]

[KEY]
D Drawings.
M Memoirs.
V Various.
S Sitting in the Halls of Study.
Cr Credits.

------------------------------------+------------------+-------
II. EXECUTION OF WORK. | Number of |
+----+---+---+-----+
| D | M | V | S | Cr
------------------------------------+----+---+---+-----+-------
First Part. | | | | |
Front of Cormontaigne | 1 | | | 20 | 90
Second Part. | | | | |
Plate 1. Construction of Project | | | | |
on Level Ground | 1 | | | 8 | 35
Plate 2. Project on Level Ground | 1 | | | 28 | 125
Memoir on ditto | | 1 | | 6 | 55
Plate 3. Project on Hilly Ground | 1 | | | 20 | 90
Memoir on ditto | | 1 | | 3 | 30
Plate 4. Project of Details. Plan | 1 | | | 20 | 90
Plate 5. Project of Section. Plan | 1 | | | 10 | 45
Abstraction of Measurements | | | 1 | 3 | 25
Plate 6. Removal of Earth | 1 | | | 11 | 50
Memoir on ditto | | 1 | | 2 | 20
Register of ditto | | | 1 | 3 | 25
Estimate of the Project | | | 1 | 1 | 10
Plate 7. Project of Improvements | 1 | | | 30 | 135
Plate 8. Details of ditto, | 1 | | | 6 | 25
Memoir on ditto | | 1 | | 2 | 20
Balance of Deblais and Remblais | | | 1 | 5 | 45
Third Part. | | | | |
Project of Attack | 1 | | | 30 | 135
Journal of the Siege | | 1 | | 4 | 35
+----+---+---+-----+-------
Totals | 10 | 5 | 4 | 212 | 1,085
------------------------------------+----+---+---+-----+-------

RECAPITULATION OF THE CREDITS OF INFLUENCE.

Lectures, 165 }
Execution of Works, 1,085 } 1,250

------------------------------------+--------------+-----
II. STUDIES AND EXECUTION | Number of |
OF WORK. +----+---+-----+
| D | M | V | Cr
------------------------------------+----+---+-----+-----
First Part. | | | |
Front of Cormontaigne, | 1 | | 20 | 90
Second Part. | | | |
Plate 1. Construction of the | | | |
Project on Level Ground, | 1 | | 8 | 35
Plate 2. Project on Level Ground, | 1 | | 28 | 125
Memoir, | | 1 | 6 | 55
Plate 3. Project on Hilly Ground, | 1 | | 20 | 90
Plate 4. Details of the Project, | 1 | | 10 | 45
Memoir, | | 1 | 3 | 30
Third Part. | | | |
Plate. Project of Attack, | 1 | | 30 | 135
Journal of Attack, | | 1 | 4 | 35
+----+---+-----+-----
Totals | 6 | 3 | 129 | 640
------------------------------------+----+---+-----+-----

RECAPITULATION OF THE CREDITS OF INFLUENCE.

Lectures, 160 }
Studies and Execution of Work, 640 } 800.

RECAPITULATION FOR THE ENGINEERS.

[KEY]
Cr Credits for Lectures.
NL Number of Lectures.
+A With application.
-A Without application.
T Total Credits.
I Number of Interrogations.

------------------------------------+----+-----------------+---
| | Cr |
I. LECTURES. | +-----------------+
| NL | +A | -A | T | I
------------------------------------+----+------+----+-----+---
First Part. | | | | |
Study of Existing Fortification, | 10 | 4.5 | 21 | 26 | 1
| | | | |
Second Part. | | | | |
Principles of the Art | | | | |
of Fortification, | | | | |
First Section. Fortification | | | | |
on Level Ground, | 19 | 24.0 | 9 | 33 | 2
Second Section. Fortification | | | | |
on Hilly Ground, | 26 | 36.0 | 6 | 42 | 2
Third Section. General Questions | | | | |
on Fortification, | 5 | 1.5 | 12 | 13 |
Third Part. | | | | |
Attack and Defense Places, | 24 | 24.0 | 24 | 48 | 2
+----+------+----+-----+---
Totals | 84 | 90.0 | 72 | 162*| 7
------------------------------------+----+------+----+-----+---

[* The number 162 is applicable to the Interrogations.]

VI. PROGRAMME OF THE COURSE OF TOPOGRAPHY.

The course of Topography comprehends two parts.

The first relates to the art of topographical drawing, and the second to the art of making topographical surveys. Both parts are carried on _pari passu_; but as the order in which the different branches of the instruction can be given depends very much on the other works carried on in the School, it will be more convenient to give the programme for each separately.

FIRST PART.--INSTRUCTION IN TOPOGRAPHICAL DRAWING.

The instruction in topographical drawing comprehends lectures and exercises in graphical representation. It is based on a complete exposition of the conventional principles of this species of drawing, and it is illustrated by engraved examples of the characteristics adopted for the representation of the various details.

_First Section.--Lectures._

The lectures have for their object the explanation of the general principles of the instruction in topographical drawing, and the geometrical conditions which should regulate the shading of maps and their reduction. They immediately precede the exercise to which they relate.

Lecture 1 relates to small maps, copies, and reductions of these; and it explains the object of topographical maps, the various kinds and the different scales generally used. The manner in which the form of the ground is represented by equi-distant contour or level lines is also explained, and mention is made of the conventional tints used, and the species of writing and value of the scale employed.

Lectures 2 and 3 relate to the execution of shaded plans by the brush and the pen, under different circumstances of light and shade.

Lecture 4 explains the different methods for reducing topographical maps, also the description, mode of using, and verification of pentagraphs.

_Second Section.--Exercises._

These exercises are intended to teach the students the conventional signs used in topographical drawing, and to give them facilities with the pencil and brush for producing shaded maps, and in reducing them from one scale to another.

SECOND PART.--INSTRUCTION IN TOPOGRAPHICAL SURVEYING.

This instruction comprises:

1st. Lectures given in amphitheatre.
2d. Practical lectures or exercises.
3d. The execution of topographical surveys.

_First Section.--Oral Lectures._

These lectures are divided in two classes, which comprehend:--

1st. Those relating to the description of the instruments, and of the
methods used in topography.

2d. Those which have reference to the manner in which the students should proceed in the execution of the work, and principally of surveys of limited extent.

Eight lectures are devoted to the description of the various instruments, the method of adjusting their errors, and the manner of using them, as well as to the different ways of proceeding in topography; touching also on the various modes of measuring distances, with descriptions of the compass, plane table, and instruments used for leveling, and on the taking observations for and preparation of sections, and the orientation of maps.

Four preparatory lectures are given, showing the manner in which the students should proceed when on the ground to make a survey of small extent.