1847.] 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



157 



don district, but Government docks ^it Deptford, Greenwich and 

 Woolwich, whicli, witli the numerous small basins belonging to ship- 

 builders and merchants, present an accumulation of works of this 

 kind, not elsewhere to be met with, though the area of the Liverpool 

 docks is much more considerable. Another very numerous class of 

 works in the Thames are the landing piers, some on a considerable 

 scale. Mr. Cresy notices the Gravesend piers, but not that at South- 

 end. 



In adverting to the e;ist coasts of the island, the author describes 

 some of those harbours whicli have given so much trouble to the en- 

 gineer, on account of their shifting channels, and the silting up of 

 their basins. Of Wells harbour he gives a very curious illustration. 



It may very well be conceived how well a review of the harbours 

 and ports of England is calculated to bring under the notice of the 

 professional read^'r a number of works which, however well known in 

 their respective localities, are not familiar to distant engineers, and 

 the particular value of a work of this kind is, that in this way it en- 

 larges the sphere of professional observation, and in so far of profes- 

 sional experience. This is particularly desirable in the present state 

 of engineering, when an engineer from the south may be sent to exe- 

 cute hydraulic works in the north, or an engineer from the east be 

 despatched to the west, and so forth. Were this experience more 

 diffused, we should not see cases, as we have recently done, of steep 

 stone walls being run up as sea walls, under the idea that with strength 

 of material, good masonry, and plenty of concrete, the engineer had 

 done all that was required of him, and that the sea would not tumble 

 it down. 



In the present day, railway engineering and surveying employ many 

 members of tlie profession, whose chief experience is in connection 

 with earthworks, so that when they come to be employed either 

 generally in hydraulic engineering, or are required to execute works 

 of that class in the cunstruction of a railway, they are very apt to find 

 the want of a more extended experience. Hydraulic engineering is 

 so ditferent in its character, and in its application — it varies so much 

 in its forms, according to the localities in which it is practised, that it 

 is well calculated to bewilder the uninitiated or the inattentive. If 

 an engineer runs up a railway embankment, or a viaduct, all he has to 

 care about is that it be made of sufficient material, and with sufficient 

 workmanship, and he has no need to think abjut it again, for it will 

 stand for ever. Not so if he puis a pier in the sea, or builds a quay 

 wall; in such case, it will require something more than bricks and 

 mortar to secure the efficiency of the work, for though he may lay 

 down what he consideis a very strong and sufficient work, it may be 

 that the stronger and the more rigid his materials, the more certainty 

 of its being swept out to sea. Hence the very serious complaints 

 that we hear of the unsatisfactory nature of so many of our hydraulic 

 works; for if in our railway works we are as it were spotless, and 

 without blame, our harbours are perpetual sources of annoyance and 

 complaint. We are therefore particularlv glad to see a work like 

 Mr. Cresy's, which carries out on a large scale, and in a comprehen- 

 sive manner a design, which in the pages of the Journal we have 

 only been able to do piecemeal, and in a very imperfect manner. 



Mr. Cresy gives plans of most of the docks in the Thames, with 

 sections of the entrance locks, and also describes the docks at Sheer- 

 iipss. The Hull Docks are given in great detail ; Spurn Point aftbrds 

 the author an opportunity of describing the old lighthouse, built by 

 John Snieaton. Hartlepool Docks are also described, and a plan is 

 given. 



Many of the Scotch harbours have of late years been improved at a 

 great expense, and the present work contains plans of most of them. 

 Among them we may notice Leith and Dundee. There is also an ac- 

 count and engravings of the Slip at Dundee. Gourdron Harbour, by 

 Telford, is a specimen of a small fishing harbour among rocks. Aber- 

 deen Harbour is accompanied by a plan ami engravings, representing 

 the masonry works. Peterhead is another specimen of a harbour 

 constructed among the rocks, and which was partly executed by 

 Smeaton. Frazerburgh and Burglihead are also represented in plans. 



Findhorn, Avoch Harbour, Cullen, Fortrose, Mahomac, Kirkwall, 

 Kyle, Rhea, Tabermory, East T.ubet, Small Isles Pier, Feoline, Cor- 

 raa, Androssm, are some of a multitude of works constructed ou the 

 Scotch coasts. Of all those named, plans and other engravings are 

 given in the present book. Of the vvoiks in t!:e Clyde we do not 

 however notice such ample details. 



Liverpool, of course, gives an opportunity fur lengthened description, 

 but in ihis case also we think Mr. Cresy's details might have been 

 given fuller witii much advantage. His subject is however so exten- 

 sive, his space limited, and the amount of information he li.is giv.-n so 

 great, that we cannot quarrel with him even about Liverpool. 



Holyhead Harbour is described, and we may observe that this 



eiicyclopadia will be found a work of easy reference for plans of 

 docks and harbours. 



St. Ive's Harbour and Plymouth are the chief illustrations on the 

 West coast, but the Breakwater and the E<ldystone Lighthouse come 

 in for an ample share of description. Many of the courses of the 

 lighthouse are shown, so as to exhibit the manner in which the work 

 was tied in by dovetailed and jointed masonry. 



Dover and Ramsgate are the plans given on the South-east coast, 

 with a copious account of the works. The Bay of Dublin, with Kings- 

 town and Howth, serve for examples of Irish works. Jersey Harbour 

 and St. Aubin's close the list of harbours. 



Among the lighthouses, of which numerous examples are given, we 

 notice theomission of castiron lighthouses and screw-pile lighthouses, 

 which are recent additions to the resources of this department of en- 

 gineering. 



As exemplitications of ancient art, Mr. Cresy gives some of the old 

 gates and castles dispersed throughout the country, and thence he 

 proceeds to bridges. 



We are not quite disposed to concur in his dictum that no bridges 

 of any consequence in tliis country were erected previous to the Ro- 

 man invasion, for we think he has given evidence to the contrary in 

 the case of Old London Bridge. Anciently, bridges' were erected of 

 timber in preference to stone, because timber was the material at 

 hand, the cheapest and the most available, as it is used for the same 

 reasons at the present day in many parts of America and Europe. 

 Mr. Cresy gives a history of bridges in England, o! which we shall 

 avail ourselves of some extracts. 



" Bridges. — We have no evidence of any bridges of consequence being 

 erected previous to the Norman conquest, and the names of our principal 

 towns on the bauks of rivers, having the word ford attached to them, seems 

 tu conlirm the oplDioii that none existed. Folloivinc; the course of the 

 Watling Street, or great Roman road over the iMedway, we meet with 

 Aylesford ; over the Darcnt, Dartford ; the Cray, Crayford ; the Ravens- 

 bourue, Deepford ; and so witli most other rivers in England. The capi- 

 tal in all probability would first have a bridge in preference to a ferry, 

 which is noticed over the Thames. \l'e have an account of a timber brid^'e 

 constructed by Etheldred in 1002, which lasted many years, and also of 

 another built in 1105. 



The first stone bridge was begun in 117G, by the celebrated Peter of 

 Colechnrch, who continued the work during the reigns of Henry II., 

 Kichard I., until the second year of the reign of King Juhn, when he died, 

 and was buried in the crypt of the chapel erected over the centre pier. 



It appears to have been the custom with the society called the Brothers 

 of the Bridge, when any member died during the superintendence of any 

 imporlaut work, to have his remains entombed within the structure; and 

 as all great bridges were provided with a chapel and crypt, every means 

 was afforded for ihe performance of the annual rites that were usually in- 

 stituted. The great bridge at Avignon, when built by S. Benezet, or 

 Johannes Benedictus, the first brother and founder of the order, had such 

 a chapel, where he was buried in 1222. 



This stone bridge was 926 feet in length, 13 feet in width, and 60 feet 

 in height al)ove the level of the water. It contained a drawbridge, and 

 niueleen broad pointed arches, with massive piers, varying in solidity from 

 25 to 34 feet, raised upon strong elm piles, covered wiih thick planks, 

 bolted together. 



Timber bridges of very simple construction were long made use of over 

 Ihe w ide rivers in England, but no skill was exhibited in the framing, nor 

 any further mechanical principle than that of strength; trees merely 

 squared, were laid side by side, at right angles with the stream, supported 

 on a single row of perpendicular piles, or several rows parallel to each 

 other, capped and cross braced, and sometimes planked over to the height 

 that the water rose, the space between being filled in with stones. The 

 roadway was cross-planked, covered with chalk and gravel, and frequently 

 required repair, in consequence of the air not being admitted to the upper- 

 side of the planking. 



It would be an endless task to ennnierate all the bridges erected in Eng- 

 land by the freemasons of the middle ages ; many were built, as has been 

 observed in the same manner as the vaults of the chapter houses and ca- 

 thedral churches; after the piers were carried above the level of the 

 slreain, ribs of stone spanned the opening from one pier to the other, and 

 supported a rubble cunslructiun l-iid above lliem,an arrangement combining 

 both economy and convenience, in subsequent instances we see one or 

 more rings of voussuirs spanning a nvcr, upon whicli slabs of stone are 

 laid, and llie bridge completed ; but it must be borne in mind that such 

 ribs only serve the purpose of centres, and cannot have the strength of our 

 modern bridges, where a wedge-like form is giveu lu every portion of the 

 sluiic. 



Alter the reign of Henry VIII. bridge-building underwent a consider- 

 able change ; timber constructions again became very common, and some 

 of the principal livers \Ncre crossed by them. In Ihe year 1G36, Inigo 

 Jones erected a bridge at LlauwasI in Denbighshire, after the nielhod prac- 

 tised in Il.ily, which was the model for some of the succeeding structures. 



It was formed of three segmenlal arches, the middle spanning 58 feet, 

 with a versed sine of 17, and the breadth of the softite of tlie arch 14 feet. 

 The depth of the voussoirs, measured on the face, was IS inches, the piers 



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