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THE KING'S - QUEEN'S CURTAIN WALL AND THE OUTER WORKS

BY

JEAN HANKEY

December 1967

(Fortress of Louisbourg Report H B 9)

NOTE:
Presently, the illustrations, graphs and endnotes are not included here.
For these, please consult the original report in the archives of the Fortress of Louisbourg

THE KING'S - QUEEN'S CURTAIN

First of all, this report will outline the construction chronology of the curtain wall. Then, it will discuss the various parts of the curtain in as much detail as possible. The development of the second part of the report, the outer works, will follow a similar pattern.

On the 1723 map, a projected plan for the fortress of Louisbourg [1] the curtain wall between the King's and Queen's bastion has the following parts: a rampart, a terreplein, a banquete, a parapet, a ramp, and a postern tunnel. The demolition map of 1760 indicates that this curtain has all of the above features except the ramp. [2] The historian must find the record of its construction and changes. Since the fortress is presently being restored to its state in 1745, the period from construction to 1745 is especially important. However. as this wall is excavated next summer, the archaeologist will find evidence of any changes made up to 1760. For this reason, it is important that the entire period from construction to demolition be carefully researched and analyzed.

Work was not begun on this curtain wall until 1731. Construction was hindered by the presence of water and rocks in the area. By the fall of that year, Verrier wrote that the postern tunnel had been raised in the middle of the wall and that construction of the escarp wall had begun. Next year, if the weather were fine, he planned to raise the wall eight to nine pieds in less than a month and a half. [3, 3a]

In 1732, the work progressed well. By the fall of 1732, Verrier could inform the French ministry that the escarp wall of the curtain had been constructed in masonry to a height of approximately twelve pieds. [4, 4a] This was confirmed by the map of 1732-3. Near the middle of the wall and almost perpendicular to it, the passage for the postern tunnel could be seen. Some of the ditch had been dug out and part of the rampart had been banked. [5] A profile MN was taken through the wall midway between the postern tunnel and the re-entrant angle of the King's bastion. Approximately three-quarters of the revetment of the rampart had been built, or precisely the escarp wall had been raised thirteen pieds. The wall was ten pieds thick at the base and eight pieds at the top of the work completed. [6]

By June of 1733, le Nornant was unable to assure the French minister that the masonry of the curtain's escarp was completed. [7] Verrier, in his letter of October 1733, informed the minister that the curtain wall had been entirely built up to the cordon level. [8, 8a, 8b, 8c] The legend of the 1733-7 map stated that the escarp wall of the rampart had been raised to a height of twenty pieds. The rampart had been banked so that there was a regular slope towards the interior of the town. [9]

The 1734-3 Verrier map indicated that the terreplein of the rampart had been banked, and the interior slope had been finished. A ramp gave access to the terreplein from the interior of the town. The postern tunnel appeared to be almost midway in the curtain wall. but closer to the Queen's Bastion. Work had not yet begun on the parapet. [10]

A profile AB was taken through the wall between the postern tunnel and the King's bastion. It indicated that the escarp wall had been built up to the cordon level. The revetment had a width of nine pieds at the base and six pieds at the top. The finished masonry stood twenty pieds high. [11]

The legend of the 1735 Verrier map stated that "Courtine ou il n y a que le parapet en maçonn. et en terre a faire, le terreplein es fait". The ditch was still being dug out. [12] However, by November of 1736, St. Ovide et Le Nomant could write that "on a elevé le Parapet interieur et Exterieur de la Courtine entre le Bastion du Roy et celuy de la Reyne ... [13] The curtain wall had been built. All that remained was the sodding of the parapet. [13a]

In 1745, John Eliot in his appraisal of the situation and strength of the harbour and town of Louisbourg wrote: "The Bastions, and curtains are faced with freestone, and cased with planks as all the rest are, to prevent their falling down by the violence of the frost". [14] The weather at Louisbourg, the use of sea sand in the mortar, and the nature of the fieldstone [15] all combined to wreak havoc on the masonry. In 1746, Governor Knowles wrote to the Secretary of State that "The Works are so bad everywhere that the Walls scale every winter and its a common thing for a Coat of Masonry of 20 to 30 yards to slip away from the body of the wall and being all built of Irregular Ruff stone are no Bond any where in it - and too upright every where to support the weight of the rampart".[16]

After the period of English occupation, the French engineer, Boucher, in 1749 surveyed the situation and estimated the nature and extent of repairs that the fortress needed. For the curtain between the King's and Queen's bastion, and in fact for all the walls of the enceinte of the fortress, he recommended the use of wooden planks. The beams of the pine framework were to be embedded every four pieds in the dressed stone face of the wall and then clamped into place. This curtain required 144 pieces, 24 pieds long. The revetment would be pine planks, two pouce thick. [17] As Boucher was awaiting the arrival of Franquet, it is doubtful that his plans were ever put into effect. [18]

In 1751, Franquet did criticize the construction and state of the fortifications at Louisbourg. On the subject of the King's Queen's curtain, he stated that the wall sloped eight pieds, nine pouces towards the left flank of the King's bastion. [19] As the King's bastion had been built on the highest point of land, the Queen's bastion would be at a lower elevation. The direction of the slope of the curtain will depend on the elevation of the terrepleins of the respective bastions, and on the nature of the terrain on which the curtain wall was built.

In general, Franquet criticized the works of this front for being too low. As insufficient earth had been transported there for the initial construction, the parapets and rampart were not thick enough. He advised against adding to the present structures as the front would be protected by the proposed redout at Cap noire. The land was boggy and wet in front and thus it was impracticable to put a trench there. Nevertheless, the defenses of the second front were as good as those of any other front. [20]

Little work appears to have been done on the curtain as the wall was reported to be damaged in several places in 1752 [21] and in 1754 [22] . By the end of the second siege, the curtain wall like most of the fortress was in ruins. [23] With the English decision to destroy Louisbourg so that it could never be used again by the French, no repairs were carried out.

The Demolition Journal of 1760 describes the manner and method of the destruction of the Fortress of Louisbourg. As two galleries were considered insufficient for the King's - Queen's curtain, four mine tunnels were dug through the rampart to the escarp wall. [24] The soil was loose and full of small stones. [25] Rain slowed down the tunneling operations. Although work was begun in June, on the twenty-sixth of October, Bastide reported that the whole enceinte was demolished except half of  the curtain between the King's and Queen's bastion, the salient angle and part of the faces of the King's bastion, half a flank and face of the Dauphin, the gate and Cavalier. [26] It was not until November 8th that the mines in tunnels 16, 17, and 18 were sprung. [27] The galleries were placed about eighty feet apart in the rampart, and the end galleries were about ninety-five feet from the re-entrant angles of the respective bastions. [2] Today, this curtain wall appears as a rounded grass covered heap.

A study of the historical documents on the curtain wall will not give a complete picture of its structure. There are three profiles of this wall. The first two, the 1732 [6] and the 1734 [11] profiles, are the work of Verrier who was the chief engineer from 1723 to 1745. Unfortunately the curtain wall was not completed by 1734 so that parts of both profiles show merely proposed work.

The 1751 profile [28] was done by Franquet who was the chief engineer from 1750 to 1758. He had been sent to Louisbourg to improve the fortifications. Thus his cross-sections show not only what was there, but also his proposed changes. As the construction of the curtain had been completed by 1737, and as there was no record of any major changes made there during the first siege, Franquet's profiles should show the finished Verrier work.

It has been generally accepted that the darker lines of the profiles outline what was there in 1751, and the lighter lines, what was proposed. However, in the profile taken through the right face of the Queen's bastion it would appear that the projected charges were sketched in the darker colour. Similarly, for the section through the King's - Queen's curtain., the lighter line would seem to indicate what was there in 1751, and the darker line, the proposed changes. [28]

The problem that arises is that the dimensions obtained by scaling the three profiles do not always coincide. In fact, in certain areas the difference is major. This report will compare the dimensions of the three profiles. By this method, it is hoped that the areas of greatest contrast will become evident, and then these problems can be discussed in conjunction with the archaeological report on the same area.

• The Rampart

A rampart is "an elevated piece of ground, or a great massy bank of earth raised about a place to resist the enemy's great shot, and cover the buildings. A parapet is raised upon this bank or elevation which looks towards the country . . . A rampart ought to be sloped on both sides; that is, the mass of earth which composes the rampart, ought to be larger at bottom than at top; more or less so, according to the nature of the earth: it should be broad enough to allow the passing of wagons and cannon, independent of the parapet which is raised on it. [Charles James, Military Dictionary, London, C. Roworth, Bell-yard., Templebar, 1810].

In the historical documents, the length of the curtain wall is given as seventy-two toise. [17] In 1760, the English engineers wrote that the rampart of the curtain was four hundred and forty-four feet long. [24]

The height of the interior slope of the rampart:

The above figures given by the English engineers refer to the "perpendicular Height Within" - this has been interpreted to mean the height of the interior slope of the rampart. Thus it would appear that the perpendicular height from the base of the rampart to the terreplein increases from the Queen's bastion to the King's by almost three feet.

The width of the interior slope of the rampart:

It would seem that Verrier planned to build a steep slope, but in fact built a rather gradual one. Franquet in 1751 wanted to steepen the slope of the rampart.

The length of the interior slope of the rampart from the baseline to the terreplein level:

In this case, there is no agreement among the various sets of figures. The slope becomes more gradual as one Approaches the King's bastion.

The width of the rampart from the base of the interior slope of the rampart to the interior side of the revetement of the escarp wall:

The total width of the rampart along the level of the terreplein:

The width of the terreplein to the base of the slope of the banquette:

Note: 

When one considers these figures, one must realize 
that they must not be compared out of context. 
The proportional differences among the various profiles will affect the 
dimensions of the respective parts.

In 1751, there is evidence that there was a building constructed in the middle of the curtain wall over the postern tunnel and overlooking the ditch and the covert way. The building, twelve pieds long and eighteen pieds wide, was built of masonry and roofed with slate. [32] Franquet describes it again in 1753. [33] On the 1758-9 map, which gives a picturesque view of the fortress and the town of Louisbourg, there is a rough sketch of a building out lined by the historical documents. [34] It was probably a sort of guard house that protected the bridge that led to the place d'arme and guarded the entrance to the postern tunnel.

During the second siege, traverses were built on the terreplein of the King's - Queen's curtain to give protection to the soldiers. [35] It is not known exactly how many traverses were constructed there, but it was reported that the very number made it difficult for the soldiers to manoeuvre. [36] There is a traverse shown on the rampart between the postern tunnel and the King's bastion on the 1757-11 Map. [37]

• The Ramp

The majority of the maps from 1723 to 1751 shown a ramp cut from the glacis of the King's bastion to the terreplein of the curtain. The ramp slopes towards the Queen's bastion. There is no written evidence to substantiate the existence of such a structure. Then shown,, the ramp appears in more or less the same position, such as that shown on the following maps: 1723-1B, [1]; 1734-3, [10]; 1735-1, [12[; 1737-1, [38]; 1739-1, [39]; 1744-5, [40]; 1745-24, [41]. Then on the 1746-2, [42] map, the ramp appears in its usual place but slopes towards the King's bastion. This position reoccurs on the 1746-3 and the 1751-17a [43] maps. It is possible that the interior slope of the rampart was gentle enough that a formal ramp was not needed. As embrasures were not inserted into the parapet of this curtain during either siege, ramps for cannon were not needed.

• The Escarp Wall

The rampart of the curtain was supported on the exterior side by masonry revetment wall. This wall would appear to have a projected slope of one over six. [44] In 1760, the English engineers state that the revetment at the base is nine feet and at the top is six feet. If the "Perpendicular height Without" is interpreted to mean the height of the escarp, then, the slope of the wall is one over six. This particular information was applied to the Princess Bastion but the journal stated that "Thickness of the Revetement Much the same all along there for I shall not mention it any more." [45]

The escarp of the curtain wall suffered from the same problems as all the masonry at Louisbourg. The use of sea sand, and the climate undermined the mortar so that it was a common thing for the walls to scale regularly. As a result. it was suggested that all the walls be planked to give them further protection. Boucher suggested this in 1749 for the King's - Queen's curtain. [17] Also. he estimated that repair work should be done to the face of the escarp wall. [46] The escarp of the curtain wall was not badly damaged in the first siege and Franquet in 1751 proposed that the revetment be repaired with masonry. [47] Little work seems to have been done as the wall is reported to be still damaged in 1752. [21] After the second siege, Colonel Bastide reported that face of the wall was broken, and as much as two feet had fallen-in. To properly repair the wall, another coat of masonry was needed. [48] The engineer, Poilly reported in his journal that "son Escarp dans le plus pitoyable état." [49] The 1758-16 map is concerned with "Shrewing the ruinous condition of the Scarp Walls towards the land ..." and indicated that the Queen's curtain was in a damaged condition. [50] With the decision to destroy Louisbourg by careful mining, no repairs were carried out.

A cursory study of the three profiles will indicate a basic problem that must be studied and evaluated. Both Verrier profiles indicate that the escarp wall is raised in masonry up to the cordon level, and then the parapet is erected vertically from this level. The exterior revetment of the parapet is not as thick as the top of the escarp. However, the Franquet profile depicts the parapet as part of the escarp wall. The parapet is built with the same slope as the escarp and the width of the exterior revetment of the parapet is a natural continuation of the escarp width.

The Verrier profiles of the curtain are cross-sections of a work that had been started but not entirely completed. The Franquet profiles, on the other hand, were made after construction was completed. All of the Franquet profiles show the escarp and parapet having the same slope, even those of the King's bastion. Verrier's profiles show two shapes. For the landward enceinte, there is a cordon level. For the quay wall and the Maurepas bastion, a sloping parapet is drawn. When the change in shape took place is not known. Whether sloping parapets were just for structures facing the water as they were easier to plank, is also an unanswerable question. Franquet by giving all the walls of the landward enceinte the same shape in 1751 has further complicated the issue. For the Queen's curtain, there is no positive evidence either way unless the archaeologist next summer can discover a cordon stone. Any such decision at the moment would be a matter of conjecture

However, as it has been established by archaeology that there was a cordon stone for the King's and the Dauphin's bastions, and as Verrier's sections for this curtain indicate a cordon level, it is possible to hypothesize that his cross-sections are valid for the King's-Queen's curtain. The problem of Verrier versus Franquet has yet to be carefully researched and analyzed.

The Escarp Wall

The width of the base below the level- of the ditch:

The width of the foundation at the level of the ditch:

The width at the cordon level - Note that for the Franquet's section which do not have a cordon level, the cordon level has been scaled as being level with the terreplein of the rampart.

Distance of the foundation below the level of the ditch:

Total height of the revetment, taken on the inside and excluding the parapet:

Total height from the cordon level to the ditch:

Height from the base of the escarp wall to the cordon level:

Note: 
The legend of the 1733-7 map states that the curtain wall has been "Elevée Reduite a 20 pieds.[9]
Verrier has informed the French ministry that the curtain wall has been raised to cordon level. [8]

• The Parapet

The actual shape of the parapet depends upon which profile is evaluated to be correct. The Franquet cross-section depicts the exterior revetment of the parapet as an integral part of the escarp wall. On the other hand, the Verrier profile suggests that the exterior revetment is a separate section of masonry, about one half as thick as the escarp wall. The interior revetment of the parapet is more or less the same for all three profiles. In the 1734-3 plan, the masonry does not appear to reach to the top of the parapet., but it does so in the 1732-4 and 1751-11 plans.

By November of 1736, "on a elevé le Parapet interieur et Exterieur de la Courtine." [13] Then the parapet was covered with sod to give it added protection against the frost. In 1751, Franquet criticized
the parapet for being too low and proposed that it be raised in grass, earth and masonry. [47] During the siege, Franquet had his men working to re-raise the parapet. [51] Thus when he was asked by
Governeur Drucour to report on the condition of the various fortifications, he could report that the parapet was still intact. [36] However, it was reported in the Amherst papers that the masonry of the inner wall of the parapet was broken and had been repaired with sod. [82] In a general memoire on Louisbourg in 1758, it was reported that the parapets of the entire enceinte were too low by a foot and not of a conventional thickness. The earth used for the parapets had no more stability than peat. [52]

The Parapet

The total width of the parapet taken at the cordon, and excluding the banquette: 

The length of the superior slope:

Height of parapet from cordon level to exterior crest:

Vertical distance from exterior to interior crest.

The height of the interior slope:

The horizontal distance from the exterior crest to the heel of the interior slope:

The horizontal distance from the heel of the interior slope to the outside face of the parapet:

Width of parapet plus banquette:

Width of earth core: [taken horizontally along level of banquette]

Height of the escarp plus parapet taken from the ditch level:

Franquet on his 1751-11 profile has written in certain elevations. It would appear that his estimated height of the escarp from the level of the ditch to the exterior crest of the parapet is either 20, or 26, or 28 pieds, 6 pouces. It is impossible to determine the second digit of the main figure.

Height of the escarp wall plus parapet taken from the base:

In his 1749 estimates, Boucher gives the height of the Queen's King's curtain - escarp plus parapet - as four toise. [46] This problem of the escarp and parapet will have to be solved at a future committee meeting.

• The Interior Revetment of the Parapet

The width of the base below the level of the banquette:

The distance of the foundation below the banquette level:

Outside height above the level of the banquette:

Inside height of revetment [top to the base]:

The width at the top of the revetment:

• Banquette:

The total width of the banquette:

Width of the terreplein of the banquette:

Height of the slope of the banquette:

Horizontal width of the slope of the banquette:

Length of the slope of the banquette:

• The Postern Tunnel

The postern tunnel served as a means of communication between the interior of the fortress and the outer works. Unlike the two postern tunnels of the Dauphin curtain, the postern tunnel in the curtain wall between the King's and Queen's bastions appears to go more or less straight through the wall, with perhaps a slight turn, but without any right angle turns [sse maps 1732-3, 1733-7, 1734-3, 1735-1, 1761-1]

Although the documents describe it as being "au millieu de la Courtine" [3], it appears in a variety of positions, but seldom dead centre. On the 1732-3 map [5], its exit is about 32 toises from the re-entrant angle of the King's bastion. On the 1733-7 map [9], it is closer to the Queen's bastion - 41 toises from the King's bastion. On the demolition map of 1760 [2], it is again closer to the Queen's bastion - 170 feet from the re-entrant angle of the Queen's bastion, and 350 feet from the re-entrant angle of the King's bastion.

In 1729, there is an order for cut stone for the posterns [53], this was probably used around each door of the tunnel. In 1750, Boucher mentions the excavation of a new well near the postern tunnel. [54] It is likely that the postern tunnel was damaged badly by the demolition as mine tunnel 18 was dug very close to the passage of the postern tunnel.

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