September 22. 1898] 



NATURE 



507 



and currents, depth of water in the port itself and in its ap- 

 proaches from the sea, the possession of soil adapted to the 

 foundations of docks or quays, and ready access to suitable 

 materials for cheap and efficient construction. 



While recognising to the full the great advantages of such 

 physical endowments in the development of a great port, one 

 cannot but remember that they form only part of the problem, 

 and that the business of engineers is to modify and direct the 

 great forces and characteristics of nature for the use and con- 

 venience of mankind. We have, in fact, to make the best of a 

 locality which may or may not be promising in the first instance, 

 and history shows us that there are few places which are hope- 

 less for our purposes. Thus while, on the one hand, we see 

 many harbours in this country which inherit from nature every 

 feature to be desired for the establishment of a port, but which 

 remain useless for that object, so, on the other hand, we find 

 many of the great centres of trade established in situations 

 which possessed no such advantages, and where almost 

 everything has had to be supplied by painful exertion and 

 great expenditure. 



As examples of these facts, I may point to the remarkable 

 progress of many commercial ports situated in localities which 

 were originally the reverse of promising from an engineering 

 point of view — to Glasgow, where twenty-six millions sterling 

 in value of exports and imports are annually dealt with in ships 

 of the largest draught, though it is placed on a river which only 

 fifty years ago was nearly dry at low water for a distance of ten 

 miles below the present docks — to Newcastle, with a present 

 trade of 13^ millions sterling, which within the memory of this 

 generation was approached by a shallow river, entering a much- 

 exposed part of the North Sea over a dangerous sand bar. 

 Sixty years ago the Tyne could only receive (and that only at 

 high water) a small class of coasting vessels, whereas it is now 

 navigable for deep-draughted vessels for a distance of thirteen 

 miles from the sea. The breakwaters also at Tynemouth, which 

 have been constructed under great difficulties on a coast without 

 a single natural encouraging characteristic, not only make a 

 valuable harbour of refuge, but have, practically speaking, 

 removed the external bar. 



In a similar way, as evidence of the truth of my proposition, I 

 might point to a multitude of other instances ; to the great 

 docks of Buenos Ayres, which city, when I knew it twenty years 

 ago, could not be approached within seven or eight miles by 

 sea-going ships of fifteen or sixteen feet draught ; to Calcutta, 

 dependent on the dangerous navigation of the Hooghly, includ- 

 ing the dreaded fames and Mary shoals ; to the creation of the 

 port of Manchester, forty-five miles fiom the sea, approached 

 by a tide-locked canal which has cost thirteen or fourteen 

 millions of money in its construction ; to the great recent de- 

 velopments of Rouen, Dunkirk, Antwerp, and Amsterdam ; to 

 the improvements of the Danube and the Mississippi. In all 

 of these cases the natural characteristics of the localities were 

 quite unsuited to the requirements of an advancing trade in 

 modern vessels, but the inexorable demands of commercial 

 shipping have created the supply, at the hands of engineers, of 

 improvements and modifications of nature, which are so large 

 and important that, to an unprofessional eye, they might now 

 almost appear, at least in some of the cases which I have 

 mentioned, to be physical characteristics of the locality. 



I think that we may safely say that trade will produce the 

 required accommodation, and that accommodation in itself will 

 not create or attract trade. 



Bristol is a case in point, and it is interesting to us at this 

 meeting to note, however briefly, some of the important works 

 which have altered and are altering its capacity as a port. At 

 the end of last century Bristol and its capabilities were, as they 

 have been almost ever since, the battlefield of civil engineers, 

 and we know that reports and projects were made by most of 

 the men who were then recognised as authorities. The diversion 

 of the river Avon and the construction of the floating harbour of 

 Bristol, which were carried out under the advice of William 

 Jessop in the years from 1804 to 1809, were boldly conceived 

 and ably executed. The result of the diversion of the Avon by 

 means of what is still known as the New Cut enabled the old 

 course of the river to be made into a floating harbour of about 

 71 acres, of which 57 acres are available for vessels of consider- 

 able size. The total cost seems to have been about 600,000/. 

 Though the greatest draught of water in the floating harbour 

 (some 20 feet) and the dimensions of the original locks (150 feet 

 long and 36 feet wide) may appear to us at the close of the 



NO. 1508, VOL. 58] 



nineteenth century somewhat insignificant, they were, no doubt, 

 up to the estimated requirements of that day, and I think we 

 can recognise in Jessop's work the impress of a great mind. 



The Cumberland Basin was deepened and improved, and the 

 lock accommo<lation was increased by Brunei in 1850 by the 

 construction of a lock, 350 feet long and 62 feet wide, and 

 again by Howard in 1871, who made another lock, 350 feet 

 long, 62 feet wide, with 23 feet of water at high water of neap 

 tides. This is the present limitation of the access of shipping 

 to the town docks, and though we realise its insufficiency for 

 modern vessels, we can appreciate the energy of those who 

 have gone before us, and who found the funds for or designed 

 works which have for so many years well fulfilled their purpose. 



The approach to Bristol from the sea — that is to say, from 

 King Road in the Bristol Channel — is certainly unpromising for 

 large ships, and indeed, when contemplated at low water, 

 appears not a little forbidding. Something has been done, and 

 more is now in progress, towards straightening, deepening, 

 buoying, and lighting the tortuous course of the Avon below 

 Bristol. More, no doubt, would have been undertaken in 

 former years, if the great rise of tide in the river had not pro- 

 vided, at spring tides, a depth and width for navigation which 

 were suflicient for practical purposes, until the size of modern 

 ships imperatively demanded increased facilities of approach. I 

 think it is a remarkable thing that vessels of 3000 tons burden, 

 320 feet in length, and drawing 26 feet of water, succeed in 

 reaching Bristol, and that the trade in the heart of the city con- 

 tinues to increase. 



Those acquainted with the strong tides of the Avon, or with 

 its bends, which do not exceed in places a radius of 800 feet, 

 and, lastly, with what might be the consequences of a long 

 vessel grounding in a channel which has only a bottom width of 

 100 feet, cannot but recognise the skill and nerve of the pilots 

 in navigating large vessels from King Road to Bristol. This is 

 done by night as well as by day, and so successfully that the 

 rate of insurance for Bristol is no more than it is for Avonmouth 

 or Portishead, the entrances of which are in the Severn, or than 

 for many ports situated on the open sea. 



We have similar examples of what can be done by the 

 systematic development of pilotage skill in the Hooghly, the 

 River Plate, the Yangtse Kiang, the Mississippi, and other 

 rivers where special men have been evolved, as it were, by the 

 demand, and navigate with safety and success channels which 

 are so full of dangers that they might well appear impracticable. 

 Experience, indeed, shows us that, given a trade and a depth of 

 water rendering access possible, ships will make their way to 

 ports through all kinds of difficulties and with a wonderfully 

 small margin of water under their keels, reminding one of the 

 boast of the Mississippi captain that he could take his steamer 

 wherever the channel was a little damp. 



To return, however, to Bristol and the Avon ; in spite of all 

 efforts to keep pace with trading requirements, the time arrived, 

 in 1868, for (providing improved dock accommodation, which 

 would avoid the navigation of the Avon, and at the same time 

 afford deeper locks and more spacious quays than could be given 

 in Bristol itself. The Avonmouth and Portishead docks accord- 

 ingly were built between 1868 and 1878, and acquired by the 

 Corporation in 1884. Both are fine works for their period ; but 

 even in their case the rapid development of modern shipping has 

 occasioned a demand for enlargements of the facilities which 

 they afford. Accordingly, a matter which is again agitating 

 Bristol is still further dock accommodation, and there has been 

 a sharp contention whether this should be effected by what is 

 implied in the somewhat barbarous word "dockising" the 

 Avon, or by new docks at King Road. Dockising implies the 

 construction of a weir and locks at Avonmouth, so that the Avon 

 would be impounded and make one sheet of water nearly six 

 miles long to Bristol, the natural discharge of the river being 

 provided for by outfall sluices, while the alternative of dockising 

 the Avon is to be found in great additions to the docks either at 

 Avonmouth or Portishead. 



In the peaceful atmosphere of Section G, I will not enter 

 upon the various aspects of these antagonistic proposals, and 

 will merely say that I have no doubt that in some way Bristol 

 will keep ahead of what is wanted, and that I wish the city and 

 the engineer who may carry out any of the ideas which may be 

 eventually adopted every success and satisfaction in such 

 important undertakings. 



(2) Leaving, then, for the present all local considerations, 

 and seeing that a large part of my own work has lain in the 



