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PRELIMINARY REPORT ON DAUPHIN BASTION

BY

BERNARD POTHIER

September 9, 1964

(Fortress of Louisbourg Report H B 8)

NOTE:
Presently, the bibliography is not included here.
For these, please consult the original report in the archives of the Fortress of Louisbourg

PARAGRAPH D: 

CONSTRUCTION OF THE BASTION AND CURTAIN, 1728-1737

The half-bastion to the right of the front of fortifications at Louisbourg was inspired by the theoretical considerations relating to the crown work in fortifications. Physically, the crown work is a bastion (or two, if it is a double crown work) flanked by two half bastions defending a front of land the rear of which enjoys natural cover. The natural cover to the rear of the landward front at Louisbourg, in theory at least, was the seashore with all the difficulties attending an offensive landing. 

The area of our studies included some features particular to the situation of Lousbourg. Most prominent of these was the arc-shaped horse-shoe battery with its 16 or 17 embrasures which faced back from the bastion and swept the West portion of the harbour. "Ouvrage indispensable, 'wrote Verrier, as the Royal and Island batteries were drawing to their completion in 1727, "attendu que le dedans du port ne serait pas deffendu, puisque la batterie Royale et celle de l'isle ne défendent que l'entrée (17 nov, 1727, AC / C11B / 9 / 141-147v). It is interesting to note that work began simultaneously at both the battery and the bastion. 

Verrier, probably the originator of the battery idea, for this reason felt compelled to offer an explanation and reassure not only Maurepas, the Minister of Marine, but also the Governor and Commissaire-ordonnateur at Louisbourg, that the work was essential to a defense scheme, would not encroach upon the limited area of a half-bastion, nor detract from the master plan. Furthermore, he assured the Minister that he would do his best to avoid unnecessary structures and tunnels which in a half-bastion could only be cumbersome (Idem, and plan 1727-4).

In the last paragraph we saw how, in the last days of the 1727 work season, fieldstone was stockpiled at the Dauphin bastion in anticipation of an early start on laying the foundations of the battery in the Spring of 1728.

The construction of the Dauphin bastion was achieved from 1728 through 1731. The éperon was built in 1735, and the curtain was built from 1735 through 1737. Following the actual construction of the front under study, there were two years in which repairs were effected: 1737 and 1738. These repairs and other changes and other improvements up to 1745, and for the succeeding periods of Louisbourg history, will constitute several paragraphs of this report.

In 1728, excavation was commenced simultaneously at both the bastion and battery. By early July the bastion's
flank was ready for its foundation, which, for the face, was in 1751, 11 pieds wide, and three pieds high (1751-  profile "cd"). It is not likely that the foundations of the flank were of different dimensions than those of the face. The flank commanded priority because of the need to contain the waters of the étang. We have no further information about the laying of the foundations but we do know that they were laid in 1728. 

The walls themselves, at any rate those of the face, were nine pieds 6 wide at the base (Plan 1751- profile), though dimensions derived from the plans suggest something like 12 pieds at the base, and 8 pieds at the cordon. By the end of 1728 they stood 15 pieds above the foundations.(13 Nov. 1728, Verrier, AC / C11B / 10 / 131-140). The wall of the battery stood at the level of its embrasures ("appui des embrasures") (13 nov. 1728, St-Ovide, AC / C11B / 10 / 81). Furthermore, Ganet had set his men to excavating the ditch in front of the bastion and carrying the product - earth and stone - to form the ramparts supporting the rear of the heavy masonry walls. This work continued in 1729 and was finished early in 1730. Years later, in 1745, after the siege, François Bigot, the commissaire-ordonnateur, criticized this procedure, followed throughout the Louisbourg period, as an important factor in the weakness of the whole front of the fortifications. This however is not borne out by the studies consulted on the art of fortifications. Ramparts are no firmer than when their fortified walls are buttressed by earth well packed. 

This earth and stone rampart sloped at the face and flank, as well as the curtain later, "gradual and easy into the town" (8 Oct. 1744, Account of C. B., N.S. A / 26 / 198-208). 

All the walls of these works were made of fieldstone masonry (Cf. paragraph C, p. 11). The mortar used was prepared from limestone the origins of which we have not been able to determine conclusively, though it was likely of Ile Royalle extraction. Nor can we determine conclusively from documentary sources whether the brick used at our front was purchased from New England, as were shingles and lumber in general. or whether the brick works at Port Toulouse were still producing for the needs of the Louisbourg fortifications.

The face of the Dauphin bastion was 45 toises long (derived), that of the flank, 20 toises, and their escarps both sloped 1/6. These dimensions are normal, in accord with the textbooks, though Louisbourg's bastions would certainly be termed small. Robert Auckmuty in his memoir on Cape Breton says that the walls of both bastions and curtains generally are 36 feet "above the field", but this is a very broad observation. Some of his other observations, by the way, tend to be more seriously inaccurate, such as his statement that "there is no outwork, glaces, or covert way" (The importance of Cape Breton to the British Navy, London, 1745).

We have very little information for the horseshoe battery. We are not quite sure whether it had 16 or 17 embrasures. An English traveller of 1745 claimed it mounted 10 48-pounders (1745, John Elliot,"Situation and strength....", N. S. A / 27 / 263-270), though in 1731 fourteen 24-pounders had been delivered .

The battery extended 269 pieds  from the wall of the soldiers' guard to the inside of the re-entrant angle of the
Dauphin Bastion. A vaulted passage-way (for which we have no information) between the rampart and the battery allowed access to the ramparts from the town. The height of the escarp was 14 pieds, and the parapet about 8 or 9 pieds thick. A ramp situated at approximately the centre of the battery communicated between the terre-pleine of the bastion and battery. There has been no written reference to this structure, but judging from our plans, it was perpendicular to the battery.

In front of the battery, along the edge of the harbour, was a "fauase braye", improperly designated, judging from given definitions. Its function seemed to be that of a retaining wall against the weight of the horseshoe battery. The "fausse braye" enjoyed a freestone exterior revetement, but this was not added before 1730. Its top was eventually covered with paving stone. 

By the end of August 1729, the embrasures had been built onto the battery and the flank of the bastion, 16 or 17 for the former, 7 for the latter. The face, as befitted the concept of the system of fortifications applied at Louisbourg, had no embrasures. Where angles,  bavettes and genouilleres were of freestone, the cheeks of flatstone. 

For their guns, the flank and the battery each had full length platforms of "mérizier" (15 mars 1752, Mînistre à de Raymond et Prévost, AC / B / 95 / 269-271v). The face, without embrasures or guns, was without a platform, save for the barbette (Cf. infra, paragraph E, p.). 

The construction of the embrasures (and merlons) atop the bastion and battery marked the completion of the masonry work on the battery and, save for the parapet, on the flank and face of the bastion.

There is no documentary evidence, but some of our plans suggest the ramp from the terreplein of the bastion to that of the rampart was located at the flanked angle. Other plans do not illustrate it at all. [Editor: most plans show the ramp at the shoulder angle]

The Dauphin gate was also begun in 1729, and by season's end it had risen to the impost. It was built of fieldstone covered with freestone like the rest. The gate area included the front of the tenaille; that is, the small faces adjacent to the gate. Bigot said this front was only 2 pieds thick, Duchambon said "3 pds. ou environ", and Shirley in 1745 admitted 4 feet. Bigot said there were 12 crenels on this front in 1745. The gate itself was about as strong, wrote Bigot, after the siege of 1745, as that of a "summer home", or, after Duchambon, also writing after the siege, as that of a "porte cochere". 

M. Pierre Mayrand has included the Dauphin gate in his study of Louisbourg monuments. In this report however, it may be useful to point out, without infringing upon the more detailed work of M. Mayrand, that the Dauphin gate had an entrance of 8 pieds 6-9 pieds [pouces?] wide, and 9 pieds 6 high.

This front was terminated in 1730, and Verrier requested late that year that provision be made for the arms over the gate to be sculptured in Rochefort on white stone, according to the design he himself submitted. By the end of 1730, only the interior revetement of the parapet was wanting at the area of the essential bastion-battery.

The arms for the Dauphin gate were delivered in 1731 and fitted into place. The side facing the country displayed the arms of the King, and that facing the town, the inscription "Domine Salvoom [sic] Regem Nostrum Ludovicum" (Lordg Save our King Louis). The fourteen 24-pounders mentioned above (Cf. supra,
p. 16) were also delivered that year and put onto carriages which had been built in 1730. They were placed in position and tested. In 1733, both the guns and their carriages were tarred and it was noted that this substance adhered well. 

The foundations of the curtain between the Dauphin bastion and the King's bastion were laid in 1735, and the curtain proper was raised to an average height of 7 pieds. in that year. This bridged the last remaining gap in the landward front. Just behind the curtain, between it and the property of Sieur Lartigue, were a lime kiln and basin. There is no indication that these were used for either the curtain or the bastions at either end, but it is to be presumed, as Verrier wrote in 1738 (29 December) that this was the only lime kiln in Louisbourg. Verrier further stated that the kiln was on the talus of rampart (of the curtain) and the plan 17 shows both it and the basin, with the note. 

The length of the curtain, in a derived measurement, from re-entrant angle to re-entrant angle was 95 to 97 toises. This front lay partly in the étang, and Verrier feared the possibility of overloading the curtain before the masonry became solid. Thus the reason for proceeding slowly and in several stages. In 1736, the curtain was raised to the cordon, and excavations in the ditch to the right of the étang yielded some of the earth and stone needed to form the rampart, half of which was built that year. The balance was done in 1737. The masonry parapet was built, the ditch to the left of the étang was excavated, and work began later on the masonry counterecarp. 

At either end of the curtain, near the re-entrant angles of both bastions, posterns were put through from the terre-plein of the town to the ditch. In June 1737 that near the Dauphin bastion re-entrant angle was wanting only its vaulted roof. I have found no further information on the posterns.

In 1738, there remained some 8 to 10 days work (30 Oct. 1737, Verrier, AC / C11B / 19 / 232-240) on the curtain: to lay sod on the parapet, touch up the banquette and rampart, and tramp down the earth.

It would seem from our plans that ramps led up to the rampart of the curtain from both re-entrant angles. [Editor's Note: One on left led from glacis of townward place d'arms]

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