REPORT ON THE CASEMATES OF THE KING'S BASTION
1720 - 1758

BY

WENDY STEVENSON CAMERON

Winter, 1964

Report H A 10

Presently, the illustrations, and the Mine Gallery, Couvert Way, Counterscarp, Ditch, Escarp, Counterforts, Parapet, Rampart, Casemates, and General Historical Notes attachments are not included here.
For these, please consult the original report in the archives of the Fortress of Louisbourg

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SECTION 2

REPORT ON THE CASEMATES OF THE KING'S BASTION 1720 - 1758

INTRODUCTION

The conclusions reached in this section of the report are based on a study and comparison of accounts submitted for completed masonry work. [1] These accounts are of a highly technical nature and a word of explanation regarding the figures is necessary.

Even the basic dimensions need to be considered in the context of their particular application. For example, height in this report refers not to height above ground level, but to the total height of masonry erected. Therefore, the additional "height" of the separation walls of the right flank casemates might more properly be spoken of as depth.

Plans of 1724 [2] and 1725 [3] bear out this interpretation. These two plans represent the right flank casemates as much deeper than those on the left flank or the right face. The one for 1724, the more detailed of the two, distinguishes the number of steps leading down into the casemates  -- fifteen steps on the right flank, five on the left and one on the right face. (The only casemate that appears not to have been served by steps is R.10.)

The use of the word "thickness" is not entirely consistent, It is given a different meaning in relation to the arches. In a description of the area of an arch, "width" is used for the horizontal dimension and "thickness" corresponds to "height", or the thickness of masonry and earth placed over the arch and measured from the keystone to the platforms of the rampart.

A greater difficulty results from occasional discrepancies between the accounts. There are instances when the total amount of masonry (given as the cube of the three dimensions) is the same in the accounts, but the individual figures are variously described as "height" or "width". In such cases, the reports of 1727 have been found to be generally more reliable than that of 1731. As the 1731 account is largely a copy of the earlier records its clerical accuracy is more easily questioned.

The contractor was paid according to tie amounts of material he had built into the works and these accounts were drawn up to ascertain what was owed. In totaling the area of masonry, irregular structures were treated in terms of regular figures with the same total dimensions. Therefore, neither the curve of the passage way ("corne de vache") at the left shoulder angle nor the irregular shape of casemate 8 are immediately apparent on these figures.

The "corne de vache" provides a good example of this procedure. The area of the arch is treated as a rectangle and no hint is given of its true shape. A single clue can be found in the description of the walls on either side. Instead of stating the lengths of two equal walls, the estimate is made on the basis of the total length of both sides taken together,

The diagrams represent the figures detailed below. In most respects, they have been drawn solely to illustrate these figures, not to show the casemates as they were in fact. No attempt has been made to represent non-masonry features, such as the doors, and the casemates have been drawn as if they were completely regular, with the six on each flank exactly the same size.

A few exceptions have been made, however, on the basis of the evidence provided by archaeology and by plans. The "corne de vache" is one. Also, the small spur on casemate R-7 has been added on the basis of archaeological evidence alone, as it assists in the interpretation of the figures.

N.B. The diagrams for height show the height of the separation walls, not that of the interior revetment.

There is an error in diagrams 1 and 4. A part of the sixth separation wall is shown as having been twice as wide as the remaining portion. This was not the case. The width of these walls was approximately uniform throughout their entire length.

MASONRY CONSTRUCTION

• Right Plank casemates (casemates 1 to 7)

There were 6 large casemates under the right flank, all of a uniform size, and one small casemate at the right shoulder angle. (Diagram 1)

1. Interior Revetment

Common to these seven casemates was the interior revetment. This wall was vertical because it was the came length at the top as it was at the level of its foundation; it was 118 pieds long. (Diagram 1) Its height, including a foundation 3 pieds high, was 26 pieds. The foundation was 3
pieds 6 pouces thick, while the wall above was 3 pieds thick. (Diagram 1)

2. Separation Walls

Separating the seven casemates were six walls each of which was 32 pieds long, measured from the interior revetment to the escarp wall. (Diagram 1)

The exact height of the separation walls to the spring of the arch cannot be stated with precision. According to one official return, the separation walls can be said to be as high as 16 pieds; the second account reported them to have been 13 pieds. Internal evidence throws doubt on the first figures, while the unreliability of the second account forces us to question the heights of 13 pieds. (Diagram 2)

Similarly. the thickness of the foundation poses a problem. It was either 4 pieds 6 pouces or, like the wall above it, 4 pieds. (Diagram 1)

3. Arches

The total width of the arches of the 6 large casemates measured at the level of the spring of the arch) was 96 pieds. (Diagram 2) They were 10 pieds high from the spring of the arch of the keystone, (Diagram 2) and 32 pieds long, (Diagram 1) the length of the separation walls which helped to support them.

4. Right Shoulder casemate. No. 7

Two walls, one extending from the end of the left flank interior revetment on the side of the face and the other from the 6th separation wall on the side of the flank, joined to form the area of the right shoulder casemate. (Diagram 1)

The wall on the side of the flank was 17 pieds long, (Diagram 1) 14 pieds high (Diagram 3) to the spring of the arch and 4 pieds 6 pouces thick. (Diagram 1)

The other wall is reported in 1727 to have been 12 pieds long; but this disagrees with a later account which states it to have been 14 pieds long. (Diagram 1) The height to the spring of the arch is also in doubt, being 14 pieds in one account and 12 in the other. (Diagram 3) In other words, the figures for the length and height were reversed in the 1731 account.

Because the 1727 figure s describe a casemate having the same proportions as the one outlined in both 1727 and 1731 for the left shoulder angle, we think that the error must be in the 1731 accounts.

The outside dimensions at the base of the arch above the 7th casemate were square, each side having been 17 pieds. (Diagram 1) The thickness of the vault from the spring of the arch to the top of the keystone was 10 pieds. (Diagram 3)

• Left Flank Casemates (Left Flank 1 - 7)

There were 6 large casemates under the left flank, all of a uniform size, and one small casemate at the right shoulder angle. (Diagram 4)

1. Interior Revetment

Common to these 7 casemates was the interior revetment. This wall was vertical because it was the same length at the top as it was at the level of its foundation; it was 119 pieds long. (Diagram 4) Its height,, including a foundation 5 pieds 6 pouces high, was 19 pieds 6 pouces. The foundation was 3 pieds 6 pouces thick, while the wall above was 3 pieds thick. (Diagram 4)

2. Separation Walls

Separating the 7 casemates were six walls, each of which was 32 pieds long (measured from the interior revetment to the escarp wall). (Diagram 4). The height of the separation walls to the spring of the arch (including the foundations) was 7 pieds 6 pouces. (Diagram 5) These walls were 4 pieds 6 pouces thick. (Diagram 4)

3. Arches

The total width of the arches of the 6 large casemates (measured at the level of the spring of the arch) was 96 pieds. (Diagram 5) They were 10 pieds high from the spring of the arch to top of the keystone, (Diagram 5) and 32 pieds long, the length of the separation walls which helped to support them. (Diagram 4)

4. Left Shoulder Casemate

Two walls, one extending from the end of the right flank interior revetment on the side of the face and the other from the sixth separation wall on the side of the flank, joined to form the area of the left shoulder casemate. (Diagram 4)

The wall on the side of the flank was 17 pieds long while that on the side of the face was 12 pieds. (Diagram 4) Both these walls were 7 pieds 6 pouces high. (Diagram 6) The wall on the side of the face was 3 pieds thick (Diagram 4) while that of the flank was 4 pieds (Diagram 4).

The outside dimensions at the base of the arch above were square, each side being 17 pieds. (Diagram 4; also Diagram 1) The thickness of the vault from the spring of the arch to the top of the keystone was 10 pieds. (Diagram 6; also Diagram 3).

5. Passage wav (corne de vache) at left shoulder angle

(a) The total length of the walls of this passage way was 14 pieds (Diagram 4). They were 5 pieds 6 pouces high up to the spring of the arch (Diagram 7) and 3 pieds thick. (Diagram 4)

(b) The arch above:-

The arch was 7 pieds long. Width and thickness are described variously as 10 pieds and 7 pieds 6 pouces, but the figure one account gives for width, the other describes as thickness. (Diagram 7) If the width of the arch is taken as 7 pieds 6 pouces and the total thickness of the 2 walls, 6 pieds, is subtracted from it, only 18 pouces remains for the passage way.

Thus, it seems more logical to assume that the arch was 10 pieds wide at the spring of the arch and 7 pieds 6 pouces high from the spring of the arch to the top of the keystone. These figures allow for an ample passage width of 4 pieds. (Diagram 7) (It is to be remembered that in a description of the area of an arch, "width" is used for the horizontal dimension and "thickness" corresponds to "height", or the thickness of masonry and earth placed over the arch and measured from the keystone to the platforms of the rampart.)

The fact that this explanation of the figures gives a lower vault than those of the casemates can, perhaps, be explained by the narrower distance it spanned.

• Right Face (Casemates 8 to 15; Diagram 8)

The only vaulted casemates described in the masonry accounts are numbers 8 and 9, the two adjoining the right shoulder casemate. The figures for the other casemates are incomplete and do not include provision for arches.

1. Interior Revetment (not entirely finished before 1731)

The foundation of the interior revetment was 178 pieds long, approximately 6 pieds high and 3 pieds thick. (Diagram 8)

The front of casemates 8 and 9 was built up by adding a section 22 pieds long, 9 pieds high and 3 pieds thick above the existing foundation. An exact height cannot be assigned to this part of the wall, as only an average height was given for the foundation.

2. Vaulted Casemates (8 and 9)

(a) Separation Walls.

Two separation walls served these casemates (the third wall was supplied by the extension of the interior revetment of the right flank and has already been accounted for.) (See Diagrams 8 and 1) Each wall was 15 pieds long, (Diagram 8) 9 pieds height (Diagram 9) including the height of the foundation, and 4 pieds thick (Diagram 8).

(b) Arches.

The length of the vault at the spring of the arch was 15 pieds (Diagram 8). The arches were 9 pieds from the spring of the arch to the top of the keystone. (Diagram 9) The total width of the two vaults is given as 24 pieds. (Diagram 9)

3. Casemates 10 to 15

Separation walls.

The foundations laid for these walls were 15 pieds long, an average of 6 pieds high and 4 pieds thick. (Diagrams 8 and 9

4. In addition to the masonry figures given above,  there are three items that we have not been able to locate on the right face. The incomplete state of this face makes definite conclusions about these items difficult. We hope, however, that they will become clearer in the light of further evidence.

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