610 



CIVIL ARCHITECTURE. 



B 1 1! firmed 

 met with 

 in I he 

 north-eat* 



Pottery 

 ware 



fiuod. 



Fnetk*. Uo, far and wide." Wren's Parentalia, p. 283, -'M, 



The sand hill at Paul's, in the time of the Roman 

 colony, was about twelve feet lower than it now is ; and 

 the fiver sand easier driving with the wind, lay upper- 

 most, and the hard coat of pot earth might be thus 

 made ; for pot earth dissolved in water, and viewed by 

 a microscope, is but impalpable fine sand, which with the 

 fire will vitrify ; and, of this earth upon the place, where 

 those urns, sacrificing vessels, and other pottery ware, 

 made, which, as before noted, were found here in great 

 abundance, more especially towards the north east of 

 the ground. 



" In the progress of the works of the foundations, the 

 surveyor met with one unexpected difficulty ; he began 

 to lay the foundations from the west end, and had pro- 

 ceeded successfully through the dome to the east end, 

 where the brick earth bottom was yet very good ; but 

 as he went on to the north east corner, which was the 

 last, and where nothing was expected to interrupt, he 

 fell, in prosecuting the design, upon a pit, where all the 

 pot earth had been robbed by the potters of old time. 

 Here were discovered quantities of urns, broken vessels, 

 and pottery ware of divers sorts and shapes ; how far this 

 pit extended northward, there was no occasion to examine; 

 no ox-skulls, horns of stags, and tusks of boars were 

 found, to corroborate the accounts of Stow, Camden, and 

 others, nor any foundations more eastward. If there was 

 formerly any temple to Diana, he supposed it might have 

 been within the walls of the colony, and more to the 

 south. It was no little perplexity to fall into this pit at 

 last. He wanted but six or seven feet to complete the 

 design, and this fell in the very angle north east. He 

 knew very well, that under the layer of pot earth, there 

 was no other good ground to be found till he came to 

 the low water mark of the Thames, at least forty feet 

 lower. His artificers proposed to him to pile, which he 

 refused, for though piles may last forever, when always 

 in water, (otherwise London bridge would fall, ) yet if 

 they are driven through dry sand, though sometimes 

 moist, they will rot. His endeavours were to build for 

 eternity. He therefore sunk a pit of about eighteen 

 feet square, wharfing up the sand with timber, till he 

 came forty feet lower into water and sea shells, where 

 there was a firm sea beach, which confirmed what was 

 before asserted, that the sea had been in ages past, where 

 now Paul's is ; he bored through this beach till he came 

 to the original clay ; being then satisfied, he began from 

 the beach, a square pier of solid good masonry, ten feet 

 square, till he came within fifteen feet of the present 

 ground, then he turned a short arch underground to the 

 former foundation, which was broken oft by the unto- 

 ward accident of the pit. Thus this north east coin of 

 the quire stands very firm, and, no doubt, will stand. 

 This narrative may be of use to others not to trust piles, 

 unless always, and in all parts, wet ; for almost all sorts 

 of timber under water wilt prove everlasting, but wet and 

 dry will eoon perish. The same cannot be said of iron, 

 for that will decay under water : but this has been ob- 

 served, in taking out cramps from stone work, at least 

 MX) years old, which were so bedded in mortar, that all 

 air was perfectly excluded. The iron appeared as fresh 

 as from the forge. Therefore in cramping of stones, no 

 iron should lie within nine inches of air, if possible ; for 

 the air is the menstruum that consumes all materials what- 

 ever. \\ hen there is a necessity to use iron for want of 

 stones Urge enough, care is to be taken to exclude suffi- 

 ciently the air from it. To mention another caution of 

 use to artificers ; some cornices of large projections, 

 though the upper joints are as close fitted as good work- 



A pit "ink 

 co the level 

 of the 



Thames. 



A tquarc 

 pier built. 



|>lrted 

 1710. 



Deicrip- 



tiun of 

 St Paul's; 



men can make them, yet in the- melting of mow, the wa- Practice. 

 ter will dribble through, and stain t!i cornice. The N """Y" - 

 surveyor thus avoided this inconvenience ; he caused the 

 masons so to work the stone next the joint, an to leave 

 half a quarter of an inch, rising on each side, that the wa. 

 ter might sooner fail off, than soak to the joint ; and this 

 he observed in the paving of the upper portico of 'lie 

 principal front of St Paul's ; besides, that the joints are 

 run with lead : and the same is done, wherevrr he was 

 obliged to cover with stone only." Pp. I 



" The first stone of this Basilica was laid in the year Begun 

 1675, and the works carried on with such care and indus- 

 try, that by the year 1685 (he walls of thcquire and side 

 aisles were finished, with the circular north and south 

 porticos ; and the great pillars of the dome brought to 

 the same height ; and it pleased God in his mercy to 

 bless the surveyor with health and length of days, and 

 to enable him to complete the whole structure in the 

 year 1710, to the glory of his most holy name, and 

 promotion of his divine worship, the principal ornament 

 of the imperial seat of this realm. 



" The highest or last stone on the top of the lantern, 

 was laid by the hands of the surveyor's son, Sir Chris- 

 topher Wren, deputed by his father, in the presence of 

 that excellent artificer Mr Strong, his son, and other 

 free and accepted masons, chiefly employed in the exe- 

 cution of the work. 



" Thus was this mighty fabric, the second church for 

 grandeur in Europe, in the space of 35 years, begun and 

 finished by one architect, and under one Bishop of Lon- 

 don, Dr Henry Compton." 



The piers of the vestibule stand upon an octagonal 

 plan. They have archivolts thrown over them, resting 

 upon every two adjacent piers, and forming eight ar- 

 cades. The spandrels are tilled with spheric portions to 

 the level of the summits of the archivolts, and there form 

 a complete circle. Upon this an entablature is laid, and 

 the projections, being protected at the outer edge by 

 an iron railing, constitutes what is termed the whispering 

 gallery. Above this, the cylmdric wall is raised to the 

 base, or springing of the dome. The dome is formed Dome, 

 of eighteen inch brick-work, and has a course of long 

 bricks inserted through its whole thickness at every five 

 feet in height. It was turned upon a centre, laid with- 

 out standards or supports from below, every story of 

 this scaffolding being circular, and the ends of all the 

 ledgers meeting as so many rings, and truly wrought, it 

 supported itself. The exterior dome is constructed of 

 oak timber, supported by timbers, which rest upon a 

 brick cone, two bricks in thickness. This cone springs 

 from the same base with the exterior dome, and sup- 

 ports the stone lantern or cupola, which is equal to 700 

 tons. This dome rises higher than a semicircle; and 

 the sides of its section, which are struck from centres 

 in the base line, would, if continued, meet in an angle 

 in its axis. See CAIIPENTRV, Plate CXXIX. Fig. 8. , , 

 In order to render the dome, cone, and cupola or lan- 

 tern secure, immediately under where the cone comes in 

 contact with the extrados of the interior dome, a chan- 

 nel is cut in a curbing of Portland stone, in which is 

 laid a double chain of iron, strongly linked together at 

 every ten feet, and the whole channel filled with lead. 

 There is a similar hooping behind the frieze of the pedes- 

 tal, which supports the exterior dome ; and alo four 

 others, at different heights, surround the cone which 

 supports the cupola or lantern. 



The extreme length of this edifice is 530 feet ; its Dj men . 

 breadth, exclusive of the two circular porches '250 fett ; ion. 

 and its height, from the pavement to the top of the cross, 

 is 366 feet. Height of the central nave to the crown of 





