1844.1 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



293 



THE RIVER DEE LIGHTHOUSE. 



FW. I . 



i i ' |l 



Wp are glad that, tlie ingenious inventions for constructing lis^lit- 

 houses on samls, wliicli wi' were among the first to recognize, may 

 now be considered as fully established in the catalogue of engineering 

 resources. It is by such applications of science to the useful arts 

 that engineering acquires and extends the strong hold, which it is 

 evidently taking on the public mind, and the importance which is 

 being communicated to its professors. We are fortunately a very 

 practical people, and nothing can be more welcome than those exer- 

 tions of ability conformable to our disposition, while it need scarcely 

 be said that he who invents a new machine adds to the power and 

 wealth of our common country. Thus in the instance before us, pro- 

 perly is to be secured, life preserved, and commerce extended by the 

 improvement of our harbours, and by the detection and prevention of 

 marine risks. 



The construction of Lighthouses on sand-banks is a modern inven- 

 tion, and has already been successfully adopted, as shown by drawings 

 in our .lournal, at Fleetwood, and the Maplin Sands in the Thames. 

 Both these constructions were erected by the aid of Mitchell's Patent 

 Screw Piles, t(] form the foundation. We have now to record another 

 lighthouse erected under the direction of Messrs. Walker and Burgess, 

 for the Corporation of the Trinity House, at the point of Air, in the 

 county of Flint, at the mouth of the River Dee, a short account of 

 which was given in the Journal tor last May, page 205 ; the founda- 

 tions are upon a ditferent plan to those before erected, as in- 

 stead of screw piles, cylinders were sunk in the sands to form the 

 foundations, as we shall proceed to explain. 



At low water the sands are dry, when the workmen were enabled 

 to proceed in their operations, by first sinking a slight cylinder of 

 plate iron 4ft. Gin. diameter through the sands to the depth of 4ft. ; 

 within this cylinder another cylinder of cast iron 3ft. 9in. diameter 

 and 9ft. long vfas gradually lowered through the sands by excavating 

 the sand from the insidi' by the aid of an instrument well known to 

 well-sinkers, called "A Miser;" great precaution was taken to keep 

 the cylinder perfectly perpendicular as it was lowered ; within a few 

 inches of the bottom of the cylinder a cast iron flange, 3 inches wide, is 

 cast upon the inside for the purpose of receiving the cast iron disc 



No. 84,— Vol, VII,— Aogust, 1844. 



shown in lig. 3: when the cvl 



' Kig. V!. 

 S(.C'tlon ot" Cylinder and Pillar. 



Fig. ?.. 



12 C 



inder was sunk to the depth of 12 feet, a 

 hollow cast iron piilar 13 feet high and 

 1 foot external diameter below, was set 

 in the centre of the cylinder, the foot 

 resting upon the disc at the bottom, as 

 shown in fig. 2 ; when the pillar was 

 placed in its proper position tlie snr- 

 rrunding space was tillt-d in with con- 

 crete, and ou the lop were laid large 

 stones about a foot thick, the whole 

 forming an immoveable foundation of 

 10 tons in weight. There were nine of 

 tliese cylinders, eiglit at the angles and 

 one in the centre, sunk through the sand, 

 making together a total weight of 90 

 tons to receive the lightiiouse. On the 

 top of the pillars are cast sockets for 

 the purpose of receiving the heiit or 

 curved pillars, ;;s shown in fig. 1, and 

 which werealso casthollow with sockets 

 to receive the inclined pillars upon 

 which the building was erected. The 

 piles are firmly tied together by two 

 tiers of horizontal ties all round the 

 eight sides, and again by diagonal ties 

 from the centre post to each of the an- 

 gular posts. The upper part of the 

 edifice is inclosed with Palmer's patent 

 corrugated iron plates, with a space on 

 the inside, and lining boards, which 

 form a living room for the attendants : 

 and the conical part below a small 

 kitchen and WLiter closet. The Ian- 

 thorn above is constructed of gun metal 

 in a verv superior manner. The whole 

 of the iron work was prepared by 

 Messrs. Gordon and Co., engineers of 

 Deptford, under the immediate direc- 

 tion and superintendence of Messrs. 

 Walker and Burgess. 



During the construction of the light- 

 house, and since it h;is been finished, it 

 has been exposed to some severe gales, 

 which it has withstood with remarka- 

 ble firmness. 



ARTESIAN WELLS AT ,=;OUTHAMPTON. 



During the meeting of the Royal Agricultur.il Society, Dr. Buck- 

 laud delivered a lecture on Artesian Wells, and in particular on that 

 which is now in progression at Southampton. Though uncompleted, 

 it is a work of immense magnitude, vying with the great well at Gre- 

 nelle, by which Paris has been lately supplied. The depth of the 

 SoullKun|iton well is at present l.oOU feet .Theshaft descends through 

 rs feet of alluvium, SOU feet of clay similar to the London clay (which 

 is 1 general substratum in the Southampton basin), and through an- 

 other 100 feet of plasiic clav, before it reaches the chalk, through 

 which it descends 100 feet still further. Thus from the surface a 

 well has absolutely been built downwards nearly 570 feet, and under 

 such diflicnlties from irregufirilies in the strata that four iron cylinders 

 have been placed in points where no attempt at masonry could have 

 proved successful. Not the least singular part of this work is the 

 manner in which this underground well has been built from the sum- 

 mit level downwards "into the very bowels of the land." This Is a 

 matter, however, which it would be tedious to describe; suffice it, 

 therefore, th.it after reaching a depth of nearly 600 feet, the opera- 

 tions of the masons were suspended, and the boring-rods were brought 

 into operation, and employed until, through their instrumentality, the 

 contractors have reached a depth of 1,300 feet. As might be ex- 

 pected, the supply of water is already abundant. It now rises within 

 -10 feet of the surface, and by the aid of powerful steam-engines no 

 less than 55,000 gallons n day ure literally poured into the town of 

 Southampton. It is expected that the water will soon rise to the 

 surface, when the supply will be immensely larger than even this. — 

 Hull Packet. 



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