Autobiography of Sir John Rennie, F.R.S., Past President of the Institute of Civil Engineers / Comprising the history of his professional life, together with reminiscences dating from the commencement of the century to the present time.

by Sir John Rennie

With regard to the situation of these docks and designing the plans for them, this depends upon the local circumstances and the requirements of the particular class of vessels that they are to accommodate, and the trade that is to be carried on in them. Without a thorough knowledge of all these circumstances it is impossible to give anything like a correct opinion as to their dimensions, mode of designing them, or any other particulars. I may say generally, however, that as these docks are always situated contiguous to some river or harbour, either with or without the tidal ebb and flow, the position and direction of the entrances to the docks become of the greatest importance, in order that they may not be too much exposed, and that vessels may be enabled to enter and depart with the greatest facility; and in such part of the river or harbour where there is the greatest depth of water and the best channel outwards and inwards. There should also, as far as possible, be the means of supplying the basins with clear water, in order to diminish the amount of deposit within; there should also be a smaller or entrance basin adjoining the outer lock, the level of water in which can be more readily adjusted with that of the adjacent river or harbour, so that vessels may be taken into the docks with the greatest despatch out of the reach of the currents in the outer harbour, and without the necessity of lowering the surface of the water in the inner basin.

Floating docks in general should have dry docks attached to them, for the purpose of repairing vessels; and these dry docks should communicate by means of a tunnel or culvert with the tidal river or harbour.

With regard to the warehouse accommodation for receiving and delivering the different classes of merchandise brought to or taken out of the vessels frequenting the docks, these should as far as possible be made fire-proof, and should be properly adapted for the reception of the different articles placed in them, so that they may be stowed away in the most convenient manner and be readily accessible. Where space will permit it is desirable to keep the warehouses as low as possible; by this means the damage in the event of fire will be greatly reduced, and the expense of taking in and delivering goods considerably diminished, and the cost of construction lessened also.

Between the warehouses and the edge of the dock there should be sufficient space for a road all round the warehouses; and between the road and the edge of the dock there should be landing-sheds, so that the cargoes of vessels, when discharged, may be placed there, to be examined and sorted, and from thence taken away to their destination, or delivered into the warehouses, as occasion may require. All inflammable articles, such as oils, naphtha, turpentine, tar, pitch, jute, hemp, flax, &c., should be stowed away in low warehouses or covered sheds, completely isolated, and with the interior divided into distinct compartments, with access round each. These compartments should be no larger than necessary. Railways should be laid along all the quays, and should be carried through the ground floors of the whole of the warehouses, while the upper floors should also have rail or tramways through each division of goods, with the necessary turn-tables at their intersection with each other. These railways should be worked either by steam power or horse traction, as may be most advisable. All the quays and warehouses should be supplied with a sufficient number of cranes, of the requisite strength to lift and stow away the heaviest goods. These cranes should be worked either by hydraulic, steam, vacuum, manual, or animal power, as may be most advisable; in fact, they should be so designed that they may be worked either by the one or the other, as may be required.

Fresh water should be laid round all the quays and warehouses, through iron or glazed earthen pipes, and there should always be an ample supply, either for vessels frequenting the docks, or for extinguishing fires; and for this purpose capacious tanks or reservoirs should be established at the most convenient places; and if these reservoirs cannot be made at a sufficient height so as to command the highest warehouses, then the water should be forced through the hose attached to the supply-pipes by steam or other power, as shall be found most advisable. Gas, also, in properly fitted pipes, should be distributed over the quays and warehouses, and the movable lights should be as few as possible; those that are used should be properly guarded, so that all risk of fire from them may be avoided. No lucifer-matches should be permitted in any part of the establishment, nor should smoking be allowed. By these means the probabilities of fire will be reduced; and if, notwithstanding these precautions, a fire should break out, there will be the most ample provision for extinguishing it in the shortest possible time, and with the least damage to the property.

With regard to architecture, that strictly belonging to the office of the civil engineer is of the most simple character. The buildings should be laid out in the best manner, and the most convenient for their respective purposes, and thoroughly substantial. At the same time, their exterior appearance should possess a certain degree of symmetry and dignity, so as to impress upon the spectator the idea that they are thoroughly adapted for their purpose. The materials should be chiefly iron, stone, and brick; and timber should only be used when absolutely necessary. At the same time, although it is not altogether necessary, the civil engineer should have a thorough knowledge of the five orders of architecture, and the mode of applying them; the principles of constructing and equilibrating arches of all kinds must be thoroughly understood; and if he intends to combine the practice of domestic and public architecture with that which is only strictly necessary for civil engineering, then he must enter more largely into the subject, and study the different ancient and modern styles of building.

Surveying and levelling will also form an important part of his duties. In order to understand them it is necessary that he should know thoroughly plane and spherical trigonometry, and the calculations necessarily connected with them. He should also have a certain knowledge of astronomy, to enable him to calculate the tides and other phenomena connected therewith, and to be able to lay down correct charts of any harbour or sea coast, with the soundings, currents, and winds prevailing there.

Geology will form another important department of study, without which he cannot understand the nature of the materials that he will have to deal with, such as stone, lime, cements, earths, &c.; the angles at which they will stand in making deep cuttings and embankments; the best and most durable kind to be employed in any particular work, the proper mode of working it, and how to place it in the best position so as to resist the effects of the atmosphere or running water, the concussion of waves, &c., in the most effectual manner. The study of geology will further enable him to account for the formation of shoals and any given line of coast, together with the operation of the currents upon them, and the best mode of remedying their disastrous effects; also the best plan for designing and constructing harbours on each particular coast or situation.

Again, by having a thorough knowledge of the strata and formation of any given district of country, he will be enabled to ascertain where water may be found, and in what quantity; and if he practises mining, he will be able to predict with tolerable certainty where different kinds of minerals may be obtained, such as coal, iron, lead, copper, tin, gold, silver, &c., and the mode of working them to the greatest advantage.