La maçonnerie de la Chambre du Roi (Grande Pyramide de Guizeh) : "probablement le plus beau spécimen au monde" (Howard Vyse - XVIIIe-XIXe s.)

Après un premier volet consacré à l'état des lieux des pyramides de Guizeh lorsque Richard William Howard Vyse (1784-1853) arrive au Caire pour commencer sa "campagne d'Égypte", je propose ici une lecture en diagonale de l'ouvrage de cet égyptologue britannique : Operations carried on at the pyramids of Gizeh in 1837, à la recherche d'éventuels indices sur les techniques de construction des pyramides, que les chercheurs auraient pu remarquer.
Certes, tel n'était pas le but premier de l'ouvrage, celui-ci étant plutôt un compte rendu détaillé, jour après jour, des "opérations" engagées pour inventorier les entrailles des pyramides. Mais au cours d'une trouvaille, lors de l'inventaire d'une nouvelle chambre découverte, au moment du bilan d'une journée plus ou moins fructueuse, l'auteur risque une remarque, un commentaire, une suggestion visant à mieux appréhender les intentions et savoir-faire des bâtisseurs égyptiens.
On le remarquera, l'interprétation n'est pas exempte d'hésitations ou d'imprécisions. Elle ne donne nulle impression en tout cas d'être guidée par une quelconque théorie : seul l'inévitable Hérodote reste en point de mire. Par contre, c'est le "terrain" qui parle et que l'on tente de comprendre au mieux, à partir d'une observation directe, in situ.
Toutes les citations, de 1 à 10, sont extraites du volume I de l'ouvrage. Seule la citation n° 11 est extraite du volume II.
Conformément à  l'habitude de ce blog, je laisse la place, en dépit de ses imperfections, au logiciel de traduction pour ceux qui seraient quelque peu "en délicatesse" avec la langue anglaise (voir en bas de page). Je me contente d'indiquer quelques points importants des extraits que j'ai retenus.

1 - Difficulté de comprendre la véritable raison de la construction de ces merveilleux édifices si l'on n'y voit que des monuments funéraires.
2 - Observations faites au moment d'une tentative de percement de la face sud de la Grande Pyramide : fixation et jointoiement des blocs de pierre ; nature du mortier ; provenance des pierres.
3 - État du sol de la Chambre de Belzoni, dans la seconde pyramide.
4 - Des trous remarqués dans la Chambre de la Reine, à l'angle nord-ouest de la seconde pyramide et dans d'autres endroits, et ayant servi, selon Perring, à l'installation des "machines en bois" mentionnées par Hérodote.
5 - Le Chambre de Wellington, tout comme celle de Davison : de simples vides ou "chambres de construction", pour alléger la Chambre du Roi du poids de l'édifice.
6 - Observation de trous de différentes formats à l'extérieur de la Grande Pyramide, principalement à l'angle nord-est, avec la présence d'un sillon, ces aménagements du terrain ayant, semble-t-il, été utilisés pour l'installation d'un échafaudage ou d'une "machinerie".
7 - En relation avec le récit d'Hérodote, selon lequel la chambre funéraire aurait été entourée par les eaux du Nil, donc souterraine, des travaux de creusement ont été effectués, il y a très longtemps, du côté de la face nord de la Grande Pyramide pour retrouver un éventuel couloir descendant à cette chambre. Mais sans résultat.
Par ailleurs, "un grand espace de temps a dû s'écouler avant la dissimulation effective des vraies entrées de la pyramide, par l'accumulation de pierres et de déchets, de telle manière que même leur position fut oubliée".
8 - Observation de deux pierres de revêtement, en parfait état et dans leur position d'origine. "Il n'y a aucune raison de douter que tout l'extérieur de cette vaste structure [Grande Pyramide] fut recouvert par cette même excellente maçonnerie."
9 - État du toit "incliné" de la chambre dite "de Campbell". Présence de trous sur le sol de cette chambre, apparemment pour soutenir des étais temporaires en bois lors de la mise en place du toit. Ouverture des joints. Présence de marques de carriers, probablement pour obtenir des angles droits.
10 - Plusieurs détails techniques attestent de l'importance majeure de la chambre du Roi : les canaux de ventilation, les chambres supérieures pour l'effet de décharge, le soin apporté à la maçonnerie de la chambre, "probablement le plus beau spécimen au monde".

11 – Présence à nouveau de trous sur les murs et le sol de la chambre funéraire de la troisième pyramide, comme "supports d'un échafaudage" lors de la finition des murs ou bien de la dépose du sarcophage.

1 - I had not at that time any idea that the stupendous masses of the pyramids were composed of solid masonry, and that (with the exception of the King's, and Queen's Chambers, and the adjoining passages and chambers of construction afterwards discovered in this pyramid) the apartments were invariably excavations in the solid rock. Indeed, after having ascertained the fact almost beyond the possibility of a doubt, it was difficult to believe it, or to comprehend an adequate motive for the construction of these magnificent buildings merely as sepulchral monuments over a tomb, unless it was the all-powerful influence of superstitious feelings.

2 - The excavation for a southern entrance in the Great Pyramid was begun at the distance of twenty-four feet westwards from the centre, and carried on to the depth of thirty feet, which was a work of considerable difficulty and labour, and was not finished till the 29th of May. (a) The stones were very large, and the half of each of them was keyed in under the upper layer, besides which, many of them were in slanting directions, although in horizontal courses ; it became therefore necessary to break almost every block before it could be removed. (b) The mortar was nearly as the stone itself, so that with Arab workmen, and common tools, it was a most tedious operation. To obviate some of these difficulties, I ordered the people to get up twenty or thirty feet, and to cut perpendicularly down behind the stones; but very little advantage was gained in proportion to the increased number, which required to be removed. Towards the end of this work gunpowder was used with great effect.
(a) The principal part of the blocks composing the pyramids were quarried from the rock on which they stand, and abound with fossil remains ; but, for the casing of the exterior, for the lining of the passages, and for many other particular parts, they were brought from the Mokattam, and consisted of a compact limestone which contains few fossils, and is termed by geologists swine-stone.
(b) Mr. Perring observed that the mortar used for the casing and lining of the passages was of lime only ; that in the body of the pyramid it was composed of red brick, gravel, Nile earth, crushed granite, and calcareous stone, and of lime ; and that for fillings in desert sand was employed in a grout of liquid mortar.

3 - The floor in Belzoni's Chamber [in the second pyramid] was examined, and as the eastern part consisted of rock, and the remainder of a pavement of two courses of squared stone, it was supposed that the sarcophagus might conceal a secret passage to the principal tomb, as Herodotus states was sometimes the case ; and a few blocks were taken up ; but nothing was found out either at this time or in August, when the whole of the pavement was removed by Mr. Perring, in consequence of the discovery of the large apartment in the Third Pyramid.

4 - Two parties had, on the 16th instant, begun to bore in the passage leading to the Queen's Chamber, in order to ascertain whether the communication existed, which appeared to be concealed by the stones let in under the step, where we had been so long employed. The borings were made near a round hole in the pavement, about six inches deep. Similar holes had been found in the Queen's Chamber, at the exterior of the north-western angle of the Second Pyramid, and in other places. (1)
(1) Mr. Perring says that these holes may be observed wherever the upper part of the courses of stone are exposed, and that they were intended to support the wooden machines mentioned by Herodotus for raising the stones, which he thinks were like the polyspaston of Vitruvius, but this machine is supposed to have consisted of an apparatus of blocks, and pullies, which were probably then unknown.

5 - The hole into Wellington's Chamber being practicable, I examined it with Mr. Hill. The floor was unequal, as it was composed of the reverse of the blocks of granite, that formed the ceiling of Davison's Chamber. It was entirely empty, excepting one piece of stone thrown into it by blasting. Not an insect or a bat appeared, nor the traces of any living animal. There had not been, indeed, any doorway or entrance ; and although some of the granite blocks in the southern and northern walls had lugs, or projections, yet the stones composing the roof rested upon them, so that it was impossible that they could have been moved up as a portcullis. This chamber, in fact, like Davison's and the others afterwards discovered, was merely a vacancy, or chamber of construction, to take off the weight of the building from the King's Chamber. Their dimensions are as follows : King's Chamber, thirty-four feet three inches, by seventeen feet one inch ; Davison's, thirty-eight feet four inches, by seventeen feet one inch ; Wellington's, thirty-eight feet six inches, by seventeen feet. In the ceilings alone was any exactness of construction preserved. These were beautifully polished, and had the finest joints, in order most probably to prevent the slightest accumulation of dust or of rubbish. In all other respects, the masonry in these apartments became less perfect as they ascended. The northern and southern walls of Wellington's, and of Davison's Chambers were of granite, the eastern and western of calcareous stone ; the ceiling consisted of nine blocks of granite laid from north to south, and were, like those in Davison's apartment, of a sufficient length to extend their bearings beyond the walls of the King's Chamber. The average height of the chamber (which varies, owing to the irregular surface of the floor) was about three feet eight inches. Mr. Perring, in the course of his survey, found that these apartments had been finished from the eastward, and that consequently the western sides were last built.

6 - In examining the ground to the northward of the Great Pyramid, I observed a line of rock projecting above the sand, which appeared to have been scalped down, and might, therefore, I considered, have contained an entrance to the subterraneous passage mentioned by Herodotus. It was parallel to the building, and about a hundred yards from it. But, upon removing the sand to the depth of six or seven feet, it was found to be in its natural state, and the work was given up. I at first entertained an idea that a grand ascent might have been formed from the plain below to the brow of the mountain upon which the Great Pyramid is placed ; but the side of the rock is covered with vast heaps of rubbish, fragments of stone, great quantities of coarse gravel, which have been brought from distant parts of the desert (probably from Dashoor), and with other materials, that have been used for fillings in, and for rubble work in the interior of the edifice. Two or three large holes of an angular shape have been cut in the platform before the pyramid, and a number of round ones about twelve inches in diameter, and eight or ten inches deep. The latter are in rows about five feet asunder, principally before the north-eastern angle of the building, where the blocks of stone would have been brought by the northern dyke. There is also a remarkable groove, or trench, which, as well as the holes, seems to have been used in the erection of scaffolding, or of machinery when the pyramid was built.

7 - In the course of the excavation at the northern front of the Great Pyramid, it was found that not only the lower part of it had been forced in search of an entrance, but that a large hole had been made through the pavement into a deep hollow, which had been filled up with rubble work, pieces of granite, and of other stones, and afterwards closed with large blocks, and effectually concealed by the pavement. The disclosure of it, therefore, could not have been the result of accident, but of an examination expressly made in search of a subterraneous passage, of which there is not the slightest indication in the interior of the pyramid, but where, on the contrary, an inclined passage from the regular entrance three hundred and twenty feet in length leads directly to a subterraneous chamber more than one hundred feet below the base. It is evident, therefore, that in very remote times some tradition existed of a subterraneous passage peculiar to this pyramid ; for, although the stones at the base of the Second Pyramid had been forced, yet the pavement at that place did not appear to have been attempted notwithstanding that the existence of a lower entrance must have been manifest to all, who examined the interior of that building. These facts coincide with the account of Herodotus, that the tomb of Cheops was at so great a depth, that it was surrounded by the water of the Nile, and differed from any thing to be seen in the Second Pyramid, a description the more remarkable, as it relates to the only pyramid which contains chambers in the masonry, and cannot apply to any apartment at present discovered in it.
It is difficult to imagine that the Great Pyramid was intended to be the tomb of more than one individual. Indeed the whole structure seems built for the security of the King's Chamber, and for the sarcophagus within it ; but if the dread of violation was as strongly felt as antient authors seem to describe, it is possible that the apartments and passages in the masonry were intended as a blind, and that the tomb in this, as in all the other pyramids at Gizeh, was an excavation in the rock at a depth sufficient to elude discovery. Or, on the other hand, if the testimony of Herodotus is to be refused on this point (although it has been found correct in many other instances), we must conclude that Cheops was actually buried in the King's Chamber, and not, according to the usual manner, in an excavation ; and that the unfinished subterraneous apartment was intended to deceive, and to support the fictions of the priests, which were communicated to Herodotus. It was my intention to have blasted the rock to a considerable depth, in search of a communication ; the discovery of this fissure, therefore, saved me a great deal of trouble and expense ; and as much interest was attached to this inquiry, I directed, when I left Egypt in 1837, that a shaft should be sunk in the floor of the subterraneous chamber, to the depth of fifty feet. This operation was attended with difficulty, from the want of a free circulation of air ; but, in September 1838, it had penetrated thirty-eight feet through the solid rock, without any appearance of a chamber. An excavation of this kind appeared to be the easiest way of ascertaining the truth, as it is nearly in the centre of the pyramid, and as there is no clue, by which any regular entrance can be found.
As it is evident, in many parts of Egypt, that the desert has been continually encroaching, particularly from the westward, there was probably little or no sand upon the rocks at Gizeh when the pyramids were erected. It would also appear that they were broken open soon after they were built, and at about the same time ; for at the bottom of the mounds, at the northern fronts of the two largest, the strata of undisturbed desert sand are of inconsiderable depth below the lines of rubbish produced by the first aggressions committed upon them ; indeed Diodorus Siculus states, that neither the bodies of Cheops nor of Chephrenes were deposited in the pyramids, from an apprehension of the violence to which they might be exposed ; and we know that they were open in the time of Herodotus, four hundred and forty-five years before Christ, and in that of Pliny, A. D. 79, as these authors describe their interior construction ; nor is it likely that when once the solid masonry was removed from the interior of the passages, they were ever again closed up, excepting by the effects of decay and of dilapidation. A considerable space of time must have elapsed before the regular entrances were so effectually concealed by the accumulation of stones and rubbish, that even the positions of them were forgotten, which appears to have been the case, when the Caliphs penetrated into the interior through the solid masonry ; although, as the Arabian historians relate, they seem to have possessed some knowledge respecting their construction, for in both instances, the excavations have been carried on from the centres of the northern fronts, and have been directed eastwards, at proper levels, so as to intersect the passages with an exactness, that could not have been the effect of chance.

8 - After having gone round the several works, I was sent for about two o'clock to the Great Pyramid, as the casingstones at the base had been discovered. The size and angle of the building could therefore be exactly determined, and all doubts were removed respecting a revetment. Two of the blocks were in their original position, nearly in the centre of the pyramid ; and those adjoining them to the eastward must have been covered by the mound of rubbish for a considerable time before they were removed, as the exact space, which they had occupied, was left in it, like a perfect model. Why they were thus taken out sideways, and by what means, without disturbing any part of the mass above them, it is difficult to say.

They were quite perfect, had been hewn into the required angle before they were built in, and had then been polished down to one uniform surface ; the joints were scarcely perceptible, and not wider than the thickness of silver paper ; and such is the tenacity of the cement with which they are held together, that a fragment of one, that has been destroyed, remained firmly fixed in its original alignement, notwithstanding the lapse of time and the violence, to which it had been exposed. The pavement beyond the line of the building was well laid, and beautifully finished ; but beneath the edifice it was worked with even greater exactness, and to the most perfect level, in order, probably, to obtain a lasting foundation for the magnificent structure to be built upon it. I consider that the workmanship displayed in the King's Chamber, in this pavement, and in the casing-stones, is perfectly unrivalled ; and there is no reason to doubt that the whole exterior of this vast structure was covered with the same excellent masonry.

9 - The excavation near the roof in the Queen's apartment was again resumed. The chamber over Lady Arbuthnot's (subsequently called Campbell's) was opened and minutely examined. The people employed at the mouth of the southern Air-channel could be distinctly heard from it ; its length was thirty-seven feet ten inches, and its width twenty feet six inches; it was entirely empty, without door or entrance, and seemed to have been intended for the same purpose as the chambers below it ; but appeared to be the last and to complete the series, as it had an inclined roof, like the Queen's and Belzoni's Chambers, composed of eleven slabs of calcareous stone, twelve feet three inches long. They rested upon a low wall about three feet high, which allowed for the inequalities of the floor, composed, as in the other instances, of the reverse of the granite slabs that formed the ceiling of the rooms below it ; the stone, by the side of which the entrance was worked up, was six feet six inches in thickness. Holes had been cut in the floor, apparently for the purpose of sustaining temporary supports of wood for the erection of the roof. Excepting the floor, the whole of the chamber was built of calcareous stone. The joints were open, and there were considerable settlements ; some of the stones of the roof also were cracked, which was not surprising, considering the immense weight they supported. When we first entered this chamber, the floor was covered with the same deposit of dust which we had observed in the apartments below it, and, in addition, the calcareous stones were covered with an exudation, which had the appearance of white feathers, and resembled that afterwards found in the Third Pyramid. There were many quarrymarks similar to those in the other chambers, and also several red lines crossing each other at right angles, with

black equilateral triangles described near the intersections, in order probably to obtain a right angle.

10 - (...) it is to be believed that the King's Chamber is the principal apartment, and the security of the sarcophagus within it the great object for which the Pyramid was erected. Many arguments might be adduced in support of this opinion ; amongst others, it may be observed that the proportions of the passages correspond with the dimensions of the sarcophagus, and that their arrangement seems expressly intended to facilitate the deposition, and to prevent the removal of it. The Queen's Chamber may be considered as an appendage to the King's, in the same way as the apartments in the sepulchres at Thebes. It may also, like those in David's tomb, mentioned by Josephus, have contained treasures ; but, whatever may have been the object, it has evidently been concealed with great care. It is also to be observed that the King's Chamber has been secured by four granite portcullises, and by the solid masonry with which the whole length of the passages have been closed ; that the well has been formed to supply with air the people employed in filling from the interior the reascending passage at the bottom of the great gallery, with blocks laid up in the gallery for that purpose ; and that it also afforded to them an escape by the lower passage when the work was completed. The entrance passage was probably afterwards filled up from the exterior. The great importance of the King's Chamber is also proved by the air-channels expressly made for its ventilation, and also by the precautions taken to secure even the walls from any superincumbent pressure by the five chambers above it, which are less carefully built, and of worse materials, in proportion to their distance from it ; whilst, at the same time, the exquisite finish of the ceilings in the four lower apartments prevent any accumulation of rubbish, and it would appear, also, the deposition of the sparry excrescence, which was found only in the upper. Nor should the masonry of the chamber be forgotten, which is probably the finest specimen in the world. It consists entirely of enormous masses of polished granite worked down, and laid with the greatest exactness, and has retained its original perfection for unnumbered centuries, whilst other mighty fabrics, composed of coarse workmanship and materials, have gradually crumbled away into shapeless masses of stones and of rubbish. In this instance every block is as fresh and as perfect as when taken from the quarry ; and such is the ponderous solidity and perfection of their texture, and the labour and science employed in their arrangement, that they seem to set at defiance the effects of time, and the efforts of human violence. It has been remarked that the upper chambers were finished from the east, and the vast blocks of this floor appear to have been closed in by a smaller oblong stone at the north-western corner. This had been removed, no doubt, in very early times, in search of treasures supposed to have been concealed beneath the sarcophagus. The excavation is mentioned by Greaves; and, when it was cleared out for the boring, an opportunity was afforded of observing the great care with which the supports and bedding for the blocks had been constructed, and the extraordinary manner in which they were worked and put together.

11 - The circular holes in the sides and floor of the apartment were probably intended to receive beams for the support of a scaffolding used in trimming and finishing the walls, or to assist in the deposition of the sarcophagus in the sepulchral chamber.