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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[April, 



that this roof was originally open, like the crarlle roofs of the 13th cen- 

 tury, manv of which ocnur in the churches of Yorkshire. The south door 

 was nuni cd as exhibitin); one of the finest specimens of Norman sculp- 

 ture in ihe country. The capitals of the principal pillars of the chancel 

 ■ arcbes arc in Ihe best preservation. That on the north has a group of 

 figures representing the ISaptisni. and the other the Crucilixion. It was 

 mentioned that the same character and grouping occur above the door of 

 Ihe liaptislry of the fjiurcli of St. Hasil at Bruges, known as " La Cha- 

 pellc du Saint SMUg," which edifice was certainly founded in 1082. The 

 kite-shaped .shield used in the time of \t'illiani the First, and other pecu- 

 liarities of style which occur in the sculptured figures of one of the south- 

 ern capitals, are additional reasons for assigning the date of the lltli cen- 

 tury to this building. 



March 8. — S. Angell, V.P. in the Chair. 



Mr. .T. Scott IUsseii. read the concluding portion of a paper " On the 

 Interior Farms «./ liu>Uliii!:s uitli respect to the Laws of Soinid." After 

 recapitulating bis first and second principles, he went on to examine the 

 third cause of bad qualities in the construction of a room. He showed that 

 in a large square room, of the usual form, the reflexion of the same sound 

 was carried to the speaker's ear by different paths, and in dillerent periods 

 of time; the result of which was the confusion of successive sounds and 

 syllables with each other— ami so a prolific cause of indistinct hearing. It 

 required another principle to afford Ihe remedy of these evils, and that was 

 the fourth principle— which he believed was quite new. He might ven- 

 ture to call it Ihe principle of the mm -reflexion and lateral accumulation of 

 the sound wave. It had originally been suggested to him by the observa- 

 tion of a similar phenomenon in the wave of the first order in water. This 

 wave he considen-d to be the type of the sound icave ; and on examioalioa 

 he had found experimental evidence iif the same phenomenon in the latier 

 wave. He luul observed that at angles below 45" the sound wave was no 

 longer completely rellerted from the surface on which it impinged ; and 

 that when Ihe objiquily of the wave to Ihe surface was 60°, a phenomenon 

 followed of total non-rejie.rion — and the wave continued merely to roll 

 along Ihe surface in a direction parallel to it. This fact furnished a ready 

 means to remedy the evils so often produced by the reflexions and echo 

 and interference of sound in public buildings. — W'herever it was possible 

 to place flat or curved surfaces at such angles that the direction of the sound 

 should be very oblique to the surface, it might be harmlessly disposed of, 

 and prevented from iojurious reflexion. — This was exactly what Ihe stalls 

 of a choir, the side chapels of a cathedral, and the partitions of boxes in an 

 opera house, did so successfully tor buildings of a large class. The same 

 principle enabled him to explain the M hispering Gallery of St. Paul's 

 (which is circular) and another equally celebrated, mentioned by Saunders, 

 which is perfectly straight. The same principle also explained the con- 

 veyance of sound along the smooth surfaie of a lake and over the flat sur- 

 face of a sandy desert : — as well as Ihe extraordinary reverberation or ac- 

 cumulation of sound in some portions of a building, 'I'he /("/'(A principle 

 was that of Ihe polarity of the human voice. Mr. Russell showed the 

 rapid diminution of intensity of sound on both sides of the axis of the 

 month ; — and that instead of extending in a circular wave round the head 

 of the speaker, as had been supposed, the line of hearing-distance was an 

 elongated oval extending forwards from the niouih. 



March ?2.— Mr. C. FowLER in the Chair. 



Mr. James Heli. read his essay " On Ihe Adaptation and Modification of 

 the Orders of the Greeks hy the Romans and Modems," for whicli a Medal 

 of Merit had been awarded : — 



The order, in (Jrecian architecture, constituted the chief feature, and 

 contributed its character and proportiiins to Ihe entire edifice. The column, 

 on the iutruilucliuu of the arch by the Itonians, lost its importance, and 

 togethiT with that, its extreme delicacy of finish and projjortiou ; in place 

 of which, luxurianie and richness were substituted, so as to harmonise 

 more thoroughly with the seuliments of the lioman people. This change 

 gradually led to a complete debasement of Ihe style; the arch, after ihe 

 Constantine era. gaining in importance more and more until the Pointed 

 style arose from Ihe ruins of the Classic. On Ihe revival, the Italians by 

 the sludy of Ihe antique, endeavoured to restore it to its primitive purity, 

 and many of them were eminently succisstul in the attainment of their 

 object, alliiough the painler-architecls introduced many flagrant abuses 

 both in composition and detail. In the north of Europe, where the Pointed 

 style had obtained a lirmer footing, the change was produced by the graft- 

 ing of Classic details on a Gothic outline, constituting the Elizabethan 

 and Renaissance ; and, at the same time, an increased intercourse with 

 Italy led to Ihe adoption of the new style in all its i)urity, for much of 

 which we are indebted to Sir Christopher Wren, in whose school it was 

 thoroughly naturalised. Since the middle of last century, the study of 

 Grecian remains has led to the further purification of the Roman, together 

 with a due appreciation of scune of those delicacies of form and propor- 

 tion which were previously either misunderstood or altogether overlooked, 

 although the feeling of tlie age, so far as regards detail, tends rather lo 

 imitation than lo nio<lification. To the Gerinaus, however, was due the 

 merit of Ihe most coniplilc appreciation of the works of the (Sreeks, — a 

 result which might have Ixen anticipated from the analogy between the 

 habits of Ihoiight and feeling, and even language, which may be traced 

 between the two nations. 



INSTITUTION OF CIVIL ENGINEERS. 

 Feb. 28. — Sir J. Rennie, President, in the Chair. 



A supplement to the papers on "the Ihlder or Great Sorth Holland 

 Canal" by Mr. <i. 15. \l . Jackson, was read. It contained a description 

 of the harbour and works at Nieuwediep, which might be considered as 

 legitimately connected with the Helder canal, inasmuch as they were con- 

 structed with a view of ati'ording shelter lo vessels of war and merchant- 

 men navigating the North Sea. The banks or shoals situated at the mouth 

 of the Marsdiep channel act in a peculiar manner ; they narrow the en- 

 trance, resist the undue influx of the tides, thu^ preventing injury to the 

 coast of the Zuyderzee ; they oppose difliculties to the etitrance <if hostile 

 fleets, as the navigable channels run within range of tlie protediug forts; 

 and they assist in maintaining the velocity of ilie currents which keep the 

 channels at their usual depth. On the coast of Holland the ebb-tide con- 

 tinues lo pass olT along the Noorder-gat a full hour and a half after the 

 tide has commenced flowing up along the Schiilpen-gal ; this can only be 

 accounted for by supposing that the tide runs up from the sonth-west, and 

 enters the Schulpen-gat, whilst Ihe ebb still continues, in consequence of 

 the draft of the tide northward along the coast. The Schulpen-gat and 

 Landsdiep may therefore be termed the flood-channels; whilst the Noor- 

 der-gat may be considered the ebb-channel. Upon these spots, whose 

 preservation was of such consequence to the country, the Dutch have la- 

 visheil their best care, and exercised their ingenuity. 



The shore works consisted chiefly of groynes, composed of timber piles 

 and fascines, with stone covering. The average length was two hundred 

 yards, w'itli slopes of about one in eight or ten. In consequence of the 

 report of the commission appointed in 1780, the engineers, Brunnings and 

 Gouili'ai, \vere instructed lo proceed with the formation of a warping bank 

 of fascines, 7360 feet long, with double planking guard lo accumulate the 

 sand, in order to fill up the interstices of the fascines, and llius preserve 

 them from decay. A breakviater also, 1S50 feet in length, 73 feet wide, 

 at 3 feet below high water, with slopes of one to one. This was also 

 formed of fascine beds, weighted with 2000 lb. of stone, and 4000 lb. of 

 tiles upon every superficial area of 144 square feet. The upper surface 

 was covered with matting, and made convex, the centre being one foot and 

 the sides three feet below the level of high water. Hurdling was then 

 used, and the whole was covered with blocks of stone weighing from 

 l.'iOO lb. to 1800 lb. each. An additional length of 2080 feet was subse- 

 quently built, the warping bank being completed, and by means of these 

 works the ebbslrcam was increased to such an extent as at once to deepen 

 the channel eighteen inches, although the bed was of clay. In 17S3, 

 dredging was resorted to, and, with the action of the stream, a depth of 

 nineteen feet was arrived at. The whole length of the proposed harbour 

 was then dredged to a depth of seventeen l^eet under high water level. 

 Another warping bank of 3G73 feet in length was then constructed, with 

 numerous groynes to arrest the sand and preserve the coast. A quay-wall 

 and jetty were then added ; the piles composing the latier were covered 

 with sheet lead between high water level and one foot below the ground, 

 in order to preserve them from the ravages of the Teredo Naralis, which, 

 however, it is the popular opiniou, may be also prevented by driving the 

 piles through fascines. A portion, sixty feet in length, of the breakwater 

 was torn away by a storm: this slip was filled up with large stones, but 

 they were ineflectual, and fasciues were ultimately had recourse to for re- 

 pairing the breach. Tlie depth of the chancel was thus increased lo nearly 

 lliirty-five feet, so that frigates could pass with safety. In 1789, one hun- 

 dred and fifty oue vessels were lying there at anchor, fourteen of which 

 were menofwar, and four were East Indiamen. The basin is 1292 feet 

 long, and 046 feet wide, with large storehouses, dock buildings, fortifica- 

 tions, &c., of the most solid description, and thoroughly complete for a 

 naval arsenal. The details of every part of tlie works were given. A 

 special vote of thanks was passed to iMr. Jacksou for the paper. 



Remarks. — An interesting discussion ensued, in which the highest com- 

 pliments were paiil to the author for the paper he had |)resentcd, and the 

 manner in which it was illustrated. A description was given of Dym- 

 church wall which defends Romney Marsh, an extent of 24,001) acres, and 

 also of several other sea-defences at the mouth of the Thames, and else- 

 where, in which fascines were extensively used. The Nene embankments 

 were also described. Specimens were shown of the Arundo Arcnarea, a 

 coarse grass, whose roots extend sometimes lo a length of upwards of 

 thirty feet, and whicli is emiutntly useful in securing the sand of the coast 

 from being blown or washed away. 



Among several cases of the failure of protecting-walls, one was particu- 

 larly described of a nearly vertical sea-wall, whose foundations were sunk 

 down full five feet below the shingle of the coast: the wall was built with 

 great care, and with first-rate m»iterials — it was, however, esjiosed to the 

 action of a heavy sea in North Wales. During a severe storm, the waves 

 were thrown up in a mass full forty feet above the wall, and filling from 

 that height with the force due lo such a distance and mass, very speedily 

 destroyed the whole wall. In quite as exposed a siluation, a slope, which 

 enabled the waves to expend their strength, and broke lliem up into foam, 

 did not suffer at all. Numerous deductions were drawn fioni these and 

 many other instances, all unfavourable to the theory of vertical sea-walls, 

 which it has recently become fashionable to recommend as a theoretically 

 even more correct form, in oppositiou to the well tried plan of eminent 

 civd engineers, who have almost universally adopted slopes for resisting 

 ihe action of the sea. 



