CIVIL ARCHITECTURE. 



: .1^. 



tilt drtaytd wood it their proper toil, yet afterward* tend 

 probably to the more speedy decomposition of the wood 



we 



i'hf following, then, appear* to be the whole the- 

 ory of the dry rot, that it il a more or lest rapid decom- 

 position of the tubitance of the wood from moisture, 

 deposited on it by condensation, to the action of which 

 it if more disposed in certain situations than in others ; 

 and that this moisture operates most quickly on wood, 

 which most abound* with the saccharine or fermentable 

 principles of the ap." Thuj far Dr Parry. 



Charring of wood is known to be a most effectual mode 

 of preservation against rotting. 



The incorruptibility of charcoal is attested by nume- 

 rous unquestionable facts. At the destruction of the fa- 

 mous temple at Ephesus, it was found to be erected on 

 piles that had been charred ; and the charcoal in Hercu- 

 (Meum, after almost 200 year*, was entire and undimi- 

 niihed. 



To thi* property of charred wood Sir C. Wren doe 

 not seem to have attended, when about to build St Paul's. 

 It is said, he thought piles were not to be depended on 

 for a foundation, excepting when always wet ; and there- 

 fore dug to a great depth through a dry soil, in order to 

 come at a solid foundation for part of that cathedral. 

 See Wren'* Parenlalia. 



Ckarca). Charcoal has also been found useful as a defence to 

 the surface of wood when used as a paint. We lately 

 had a good instance of the effect of sand used for this 

 purpose. At Studly Royal we saw a temple to appear- 

 ance of stone, but which on examination we found to be 

 wood covered with paint, and dusted over with sand. 

 We were informed it had stood about 50 years ; and the 

 deception was still so complete, that the spectators sup- 

 posed the pillars to be stone, till minutely examined. 



From marble being plentiful in Italy and France, these 

 countries have been able to make a considerable use of it, 

 even in the main walls of their edifices ; but being seldom 

 found in sufficient quantities, and of proper quality, in 

 the more northern parts of Europe, it has been here 

 chiefly confined to interior columns, pavements, chimney- 

 pieces, and sometimes stairs. 



The kind* of stone are as various, as the countries in 

 which the buildings are constructed. Sandstone being 

 very generally found stratified, even in thin laminx, 

 being readily cut into different forms, and being, if pro- 

 perly selected and used, sufficiently durable, it has, in 

 northern countries, been in most frequent use. It 

 i* a general accompaniment of coal strata, and is also of- 

 ten found where the latter doe* not occur. It varies in its 

 component parts, being at different places argillaceous, si- 

 liceous, and calcareous. Its position, in the earth, as- 

 sumes all directions, from the horizontal to a vertical 

 plane. The proportional thickness of its strata, laminae, 

 or beds, varies from that of thin date to many feet each. 

 The upper beds are usually very thin or soft, or both ; 

 if sufficiently hard, they are employed in floor pavements 

 and covering roofs. Under these the beds generally, in 

 useful quarries, increase in thickness, hardness, and te- 

 nacity. The position of the laminx always require strict 

 attention, that the worked ttone may, if possible, be laid 

 in the building upon its natural bed ; for although some 

 instances occur, as in the Isle of Portland and at Grins- 

 hill, in Shropshire, where the difference is not appa- 

 rently great, yet in all stone (even granite) it is suffi- 

 ciently well known to workmen. Some stone, as that 

 of Bath, i* to soft when taken out of the quarry, as to 

 be ery conveniently worked with tools re*cinbling those 



Practke. 



Stone front 

 Tattcnboe. 



Stone in 

 ScotUwi. 



Flint*' 



used by carpenters ; yet when exposed for ome time to 

 the atmosphere, it become* hard and durable. This last, 

 indeed, cannot be deemed sand scone, being nearly alto- 

 gether calcareous. 



Besides the before mentioned, there ia a very beauti- 

 ful stone, dug in the hills near Dunstable, in the parish 

 of Tottenhoe, from whence the stone receive* its name. 

 It has the appearance of indurated chalk. It is easily 

 worked, and hardens by exposure to the weather. It 

 should, however, be placed upon a plinth of some other 

 stone, or kept by other means from contact with the 

 ground, otherwise it is, in this situation, liable to be in- 

 jured by the frosts. The house of the Duke of Bed- 

 ford, at Woburn Abbey, is built chiefly with this stone, 

 and various other large houses in the neighbourhood of 

 the quarries. Proofs of its durability may be seen in 

 many old churches. From the closeness of its texture, 

 the beauty of its colour, and the facility with which it 

 is worked into mouldings, &c. il is peculiarly fit for 

 house-building, both externally and internally. It may 

 now readily be conveyed to London, by means of the 

 Grand Junction Canal. 



The very perfect preservation of many beautiful 

 churches in the counties of Lincoln, Rutland, and North- 

 ampton, are evidence of the excellence of the stone of 

 which they are built. 



In the central parts of Scotland, different varieties of 

 sandstone, which accompany coal, are used extensively 

 in building houses, Arc. ; and this circumstance has not a 

 little contributed to the fine appearance of the new streets, 

 squares, and public buildings in the cities of Edinburgh 

 and Glasgow. 



Flint*, where they abound, and where other stone is 

 scarce, are sometimes used in walls of considerable height ; 

 and notwithstanding their small size, and irregularity of 

 shape, are broken so as to compose a face of consider- 

 able smoothness. The church and steeple of Rickman*- 

 worth, in Hertfordshire, affords a fine specimen of this 

 kind of building. But bricks or squared stones are ge- 

 nerally used as quoins for this sort of work. 



In Scotland and Sweden granite is made use of as a 

 building material. It lies in large masses, generally se- 

 parated by gunpowder into moderate, though still large 

 dimensions, which arc again cut into suitable scantlings, 

 by means of iron instruments called plugs and feathers. 

 They are not only worked into plain square forms, but 

 also mouldings of considerable delicacy, by means of 

 pointed tools of different sizes and weights. At Aber- 

 deen, in Scotland, where excellent granite is produced, 

 and the working of it brought perhaps to the greatest 

 perfection, there are handsome porticos, consisting of co- 

 lumns, bases, caps, and entablatures, executed in gra- 

 nite with great nicety, lu the middle of the city a pub- 

 lic building, wtiose front is composed of a full Doric or- 

 der, is wholly completed with tins excellent material. 

 There are two sorts of granite, the one grey and the 

 other red ; the last being the hardest, is most difficult 

 to work, consequently the former is most frequently em- 

 ployed ; it consists of feldspar, mica, and quartz. It 

 is much employed tor paving the carriage way ot streets, 

 and in the curbing of the flat side pavements ; also for 

 piers and footpaths of bridges; aud for facings and copings 

 to quays and wharfs. At Aberdeen, it is employed in 

 constructing very extensive piers, for protecting the en- 

 trance of the harbour ; and in the Eddystone and Bell- 

 &ock light -houses, it composes the facings, where they 

 arc exposed to the action of the sea. 



Whin, basalt, and tchistus, re also used in rubble Whia. 



Oranitt. 



Aberdetm. 



granite. 



