1840.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



920 



these breaks in tlie facade. That licence so congenial to artist's feel- 

 ings, seems there betrayed without violence to symmetry ; and the 

 ellect generally entailed u])on their adoption, seems lost in the happi- 

 ness of his idea. 



In the first place the front without them is sparing of details and of 

 breaks. In the second place the building itself was one dedicated to 

 mirth and pleasure : and ideas of strict utility or true support are 

 waved, when the imagination is supposed to be atl'ectcd by something 

 of the sprightly joys and jovial spirit reigning within. The exterior 

 reveals the interior; you care not as you gaze with your thoughts un- 

 disciplined upon the edifice of jileasure, whether you see the cohnnn 

 relieving a depending weight, or supporting the various breaks of the 

 entablature. The artist sought to please, and not to affect — to cheer, 

 and not to impose. 



With reference to the Persian court, in the design for the Whitehall 

 Palace. There is a freedom, an ease, nay an almost negligent air, in 

 the breaks and the figures that support them — and the object in view 

 here, I conceive was, to |ilease the eye of the king and his favourites. 

 As if stirtiiess and solemnity were, unwelcome to that monarch and his 

 court : — as if the severities of rule, and the sternness of power, were 

 to vanish at once in a building sacred to ease and kingly relaxation. 



However much we may dislike their iutroduction as a custom in 

 architecture — however nnu-li we may blame them viewed in the per- 

 spective of a street, and confusing to the eye in half profile, there 

 seems something of agreeable pleasure in their aspect when displayed 

 internally. 



In his own dwelling, free fi'om the sti-uggles of life and the world, 

 the statesman is half enchanted into playfulness, by the careless assem- 

 blage. — The accurate line, the finish of care the student displays, tend- 

 ing to renew thoughts of care and disquietude — vanish in the varied 

 forms of the columns, which ministers to his ease, sooth and trancjuilize, 

 the brow of concern. 



There is indeed a strange beauty in architecture. Like the com- 

 position of the poet and the painter, the design of the architect is at 

 once a tale of interest— a delusive fiction or a startling truth — and the 

 architect most insidiously works upon the ga^er, who most studies the 

 secrets of mental impression. 



ON SUB-MARINE FOUNDATIONS. 



Sin — There is in your last Journal a description of a light house 

 lately erected under the auspices of Commander Denham, R.N., on a 

 sand bank at the entrance of the Wyre Navigation. This structure 

 has been supported upon and secured to the bank with Mitchell's 

 patent screw moorings. The introduction of this principle to the 

 mooring of vessels is good in the opinion of those who have tried 

 them. They are durable, very compact, and take a firm hold of the 

 ground by means of the flanges, wliich make them exceedingly appli- 

 cable for that purpose ; in rivers and in harbours they can be screwed 

 down without much difficulty, through mud, sand, or shingle to a cer- 

 tain depth. They are, however, an expensive article, if we take into 

 account the providing of barges and the labour of screwing them down, 

 together with the patentee's charge for the mooring itself. 



It would therefore have conferred a favour upon the profession if 

 along with the description of the lighthouse we had been also informed 

 of the cost of its erection. I am quite sure that it might have been 

 done at far less expense on the old principle of driving piles into the 

 groimd. 



The mooring screws are stated in the drawing to be 10 feet below 

 low ivater mark, which I suppose may allow them to be S feet into the 

 sand. Now the expense of a 3 feet mooring with the patentee's 

 charge and the labour in fixing it to this depth would be about £50. 

 On the other hand the cost of driving a pile, say 12 feet into the 

 ground, with the additional length of timber, would not cost one-tenth 

 of the sum, and piles can be driven into as firm a foundation as the 

 screws. Where then is the great advantage of the screw mooring so 

 applied but to increase the expense. 



Again, in my opinion the framing ought to have been quite naked 

 from half tide upwards, to prevent as much as possible the shock of 

 heavy seas from injuring the structure, therefore, much dislike "the 

 systematic interlacing of tension rods to render the fabric sufficiently 

 opaque below the platform." I am also much mistaken if this system 

 of bracing will not cause the tide to scour away the sand from the 

 feet of the framing, and expose the screws to its action. 



No practical engineer would in my opinion have adopted such a 

 design. 



I am Sir, your obedient servant, 



0:<E Of lae Oi» School. 



TIDES OF THE OCEAN. 



Sir — The Newtonian theory of the tides liaving been questioned 

 by many, in which, I confess, I participate, I should esteem it a great 

 favour, if some of your intelligent correspondents would weed my mind 

 of the doubts that have taken deep root on this subject. 



If the moon be the infiuential cause of the rise and the fall of the 

 tides, why is her influence not universal? 



Why does she seem to exercise her influence so powerfully on one 

 sea, less in another, and not at all in others, and why is her supposed 

 jiuwer entirely subdued by the effects of particular winds on certain 

 coasts ? 



Why does the tide, ebb and flood, commence at each turn of the 

 tide to run at the bottom of the sea before the water moves on its 

 surface ? 



What is the cause that, at an island in the South Pacific Ocean, 

 the time of high water is always the same ? 



I am ;iware that the moon and the tides retrograde coextensively, 

 but this does not prove a coincidence. 



I am aware, too, that it is said, by way of establishing a theory, that 

 the Baltic and Mediterranean seas are not of sufficient expanceto ad- 

 mit of the moon's influence — although the seas are much more exten- 

 sive than the English or Irish chaimels — but the real cause why there 

 is no ebb and flow tides in those seas is, that the seas do not rise or 

 fall at either of the points connecting them with the ocean ; for the 

 flow and fall of the tides, and the velocity with which the current 

 passes out and in of a tidal harbour or arm of the sea, is governed by 

 the velocity and rise of the tides at the entrances thereto, and there- 

 fore, without looking for any other cause, here is the real cause. 



The great difference of flow in the same sea, has, hitherto, not been 

 satisfactorily accounted for. 



Thus, for example, the flow on the eastern shores of America oppo- 

 site the Straits of Giliraltar, is 30 to 4l) feet— »o«e on the latter. 



A flow on the Pentland Kerbs and along the north coast of Scotland, 

 of 20 or 30 feet ; on the coast of Norway opposite, and at the Catte- 

 gat, the entrance to the Baltic, no rise in the water. 



In the Irish Channel, on the coasts of England and Wales, the flow 

 of the tide is great ; on the Irish coast opposite, a small rise of the 

 tides. 



In the English Channel, on the French coast the flow is great ; on 

 the English coast but comparatively small. 



If an allowance is made for the particular formation of i)arts of the 

 coast, and other local circumstances, they are not sufficient to establish 

 the accuracy of the Newtonian hypothesis on the tides. 



I remain, your's, &c., 

 \4.th June, 1840. Nauticus. 



WATER OF THE VISTULA. 



Sir — In your Journal of last month there appears an account of the 

 casualty in Prussia, — the water of the Vistula having been diverted 

 from its former course, and forced for itself a passage into the Baltic 

 Sea in a new direc'.ion, at some distance from its former disemboguing 

 point, i. (. via the Old Fairwater. As the current had previously, from 

 times immemorial, passed into the ocean at the latter point, with great 

 sluicing and scouring velocity, produced an impassable bar, so will the 

 water, which now runs out at the new point, produce the like eflects, by- 

 forming a bar at its new disemboguing ]ioint. 



The bar at the Old Fairwater liaving some years back blocked up 

 its entrance, and prevented ships entering to go up to Dantzig to dis- 

 charge and load their cargoes. A new lateral cut was made, and so 

 formed a passage to sea via the New Fairwater; and at the connecting 

 part of the New Cut with the Vistula, a gate was fixed to prevent the 

 current passage running to sea through the New Fairwater, :uid al- 

 though this work has been completed for many years, no bank or bar 

 has been formed at the new entrance, so that the egress or sluicing water 

 constantly in its egress action, has blocked up the old entrance, but as 

 there is no water or current passing to sea by the new Fairwater, no 

 bar accumulates. 



The division of the current, before alluded to, cannot in any way 

 affect the entrance to Dantzig by the New Fairwater, but if the current 

 of the Vistula should continue its new course, and not again return to 

 its old channel, a material alteration will soon be discovered in the 

 bar or bank at the entrance of the Old Fairwater. 



Nauticus. 



