1850.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



tians, we are at a loss to conceive liow a people comparatively 

 ignorant of the mechanical arts could have achieved such g-igantic 

 works. Though it is probable they had contrivances either un- 

 known to lis, or now considered as comparatively new inventions, 

 yet from all we can learn from written liistory, or from their own 

 sculptured records, it seems that they depended more upon time 

 and manual labour, than upon those arts by which modern under- 

 takings are so much facilitated. It is remarkable that while the 

 Eiryptians have left us such minute and copious details respecting 

 tlieir customs, trades, and manufactures, any notice of engineering 

 works is extremely rare: this may probably have been owing to its 

 having been under the direction of the priests, and kept as a mys- 

 tery. In a bas-relief we see a seated colossus which is being 

 moved; ropes are fastened to every part of the figure, and are then 

 gathered into one knot, to make the pull e(iual; and numerous 

 strings of men are hauling it, the engineer staiiding on the knees 

 of the figure, directing their movements. In another bas-relief 

 we see oxen employed in drawing a stone. 



We are told that in building the pyramids, in order to bring the 

 stone from the boats on the Nile, a causeway was formed, 1000 

 yards long and 50 feet high, and this was prol)ably raised as each 

 successive course of stones was added, — so that each stone was 

 rolled up this inclined plane to its place. If a huge stone was to 

 be placed on the top of a wall, it was dragged up an inclined plane 

 of sand to its destination. We have an account of an obelisk 

 Su cubits in height, that had been made in the reign of King Nec- 

 tanebo; this the king Ptolemy Philadelplius wished to set up in 

 Alexandria, in honour of his sister. To this effect, Satyrius, the 

 architect, is said to have dug a canal to it as it lay on the ground, 

 and to have placed under it two heavily-laden barges. As the 

 barges were unloaded they floated higher, and thus raised the 

 obelisk from the ground. Unfortunately, we are not informed 

 how he afterwards proceeded to set it up in its destined posi- 

 tion. 



In quarrying stone, wedges were used, either of metal struck 

 with a mallet, or of drj' wood, which, when moistened, split the 

 stone. We have no reason to suppose that free labour was not 

 employed, but we know that criminals and prisoners of war were 

 sent to work in the gold mines; and those guilty of misdemeanour 

 may also have expatiated their fault in the quarries. There exists 

 an inscription at the quarries of Gertessy, in Nubia, "'I have now 

 dragged 1 10 stones for the building of Isis at Philoe," which would 

 seem to indicate a penance performed. 



The Egyptians must have been well versed in land surveying, 

 levelling, and various branches of geometry, as well as in many 

 operations requiring mathematical science. That they were early 

 skilled in forging metals and polishing stones, their works remain 

 to prove; the art of gilding was known in the reign of Osirtesen I. 

 (ItijOn.c.) We have no record of the discovery of the art of 

 manufacturing steel; and from the speedy decomposition of iron 

 and steel, few tools can be expected to remain: but we cannot 

 examine the deep and sharp cutting of the Egyptian hierogly- 

 phics, and suppose that instruments of any softer material can 

 have been used. The cuttings may have been sharpened up 

 with emery, which was within their reach in the islands of the 

 Archipelago. 



That the Egyptians were skilful engineers, as well as architects, 

 we have abundant proof. The dykes directing the arbitrary over- 

 flow of the Nile, served also as raised roads — the only mode of land 

 communication during the inundation: they followed a tortuous 

 path, visiting the various towns and villages on their way. A 

 canal was cut from the Nile to the Gulf of Suez, in the time of 

 Rameses the Great; at the mouth of this canal were sluices to 

 regulate the supply of water. And as early as the reign of Thoth- 

 mosis HI., between 1300 and 1400 b.c, the Lake Moeris was formed, 

 which regulated the overflow of the Nile in that part of the coun- 

 try, and by its means thousands of acres were irrigated, and thus 

 brought into cultivation. 



I must now conclude this sketch of the Architecture of the 

 Egyptians: space and time will not allow of more, or volumes 

 might be written on the subject. If I have said enough to show- 

 how high a place the Egyptians occupied among ancient nations, 

 and to how great an extent civilisation had been carried at that 

 remote period, I must remain satisfied — referring the student for 

 further information respecting this interesting people, to the 

 valualde works of Sir Gardiner Wilkinson, Professor Kosellini, 

 MM. Denon, Champollion, and others. 



Wilkinson's Manners and Customs of the 



Ancient Kgyptians. 

 \\'ilkin8on's 1 hebes. 



hurpe's History ot Egypt. 

 R')delliiii, Moiiuinenti d'P^gitto. 

 (Jumna, Arcliitettura Antica. 



.1ST OF AUTHORITIES. 



Labnrde's Mustrations. 



K 'berth's KgypL. 



Quiitrtm^re de Quincy. Encyclopedle lile- 



thodiqne. 

 Miss Martineau's Egypt and the Holy 



Lund. 



*,.* The Panorama of the Nile at present exhibiting at the 

 Egyptian Hall, Piccadilly, will afford the student in Egyptian 

 architecture a very clear idea of the stupendous works ot an- 

 tiquity, and well repay a visit. Of course it is to be supposed 

 the student avails himself of the Egyptian Gallery in the British 

 JMuseum, and of the Soane Museum. 



DESCRIPTION OF THE COFFERDAM AT THE 

 GREAT GRIMSBY DOCKS. 



Engineer: James M. Rendel, Esq. 



{^With an Engraving, Plate II.) 



The position occupied by tliis cofferdam is one of very great ex- 

 posure. It is open immediately in front and on the eastward to an 

 estuary 7 miles in widtli, and on the north-west to the whole cur- 

 rent of the Ilumber for a reacli of 20 miles, with a 25 feet rise of 

 tide against it on the outside, and an excavated depth of 11 feet 

 below low water immediately behind it, as necessary for laying the 

 foundations of the locks. .Moreover, the Humber is frequently 

 exposed to violent storms; and finally, this cofferdam, unlike most 

 structures of its class, must depend entirely on its own strength 

 and form of construction for the requisite stability, as there is 

 nothing in its whole length of 1,500 feet from which to derive sup- 

 port of any kind. It is therefore the more satisfactory to record 

 that the work was completely carried out without any necessity 

 arising for altering a single feature of the design in the course of 

 its execution. 



The plan of the cofferdam is a compound curve formed of two 

 circular arcs, with a straight return on the west side; and the 

 versed sine of the curved portion is f200 feet, or) ;Jth of the span 

 nearly. The dam consists of a triple line of whole timber sheet- 

 piling, of which the outside row is battered half an inch per foot; 

 and the other two rows are upright. The sheeting was all driven 

 between gauge or bay piles, placed 10 feet apart; and the three 

 last-driven piles of each bay were accurately sawn to a taper, in 

 opposite directions, so as to wedge the remaining piles of the bay 

 closely together. The average length of the piles in the first row 

 is 56 feet; and that of the other two 45 feet. They are all driven 

 to enter a bed of hard clay; but the ground through which they 

 pass before reaching this bed is of a weak and silty character. 

 The width between the first two rows of piling is 7 feet; and that 

 between the centre and back row is 6 feet. The puddle clay 

 occupying these spaces was mixed with one-fourth of small broken 

 chalk'stone for the first 5 feet in height, and perfect consolidation 

 was insured by tipping the puddle throughout, from earth wagons 

 on the top of the dam; single barrow-loads, even from that height, 

 being entirely forbidden. The front and back rows of piling are 

 secured by five tiers of whole timber double-walings; but in the 

 centre row, the three lowest tiers of waling have been replaced by 

 bands of wrougbt-iron, (i inches broad by 1 inch thick, wliicli are 

 keyed together in lengths of 12 feet, and form a continuous tie on 

 either side of the piling from one extremity of the dam to the 

 other. In tliis capacity alone they are very serviceable; but the 

 principal object of the arrangement is to insure an uninterrupted 

 surface over the face of tlie sheet-piling on both sides, in order 

 that the puddle may at all times be closely packed against it with- 

 out leaving any of those voids which are inseparable from the use 

 of ordinary timber walings in such situations, and serve as chan- 

 nels for any water tliat may pass along the through-bolts. 



Another precaution against the admission of the water was 

 observed in the arrangement of the long bolts, which were all dis- 

 tributed in such a manner as to break joint, never entirely passing 

 through the dam, but in every case terminating at the outer row 

 of piling, being screwed u)i against the wrought-iron plating, be- 

 tween which and the face of tlie piles a washer of vulcanised 

 india-rubber was introduced. The long bolts are 2,^ inches in 

 diameter at the lowest tier of walings, diminishing upwards to 

 Ij inches. 



It is, however, in the method of giving interior support to the 

 structure that the greatest constructive excellence and originality 



