placing the stone in the courses in the same direction or bed as it lay in the quarry, to prevent its splitting.

66

1885. In foundations where, from columns or small piers pressing upon particular parts, there would be a liability, from uneven bearing, to partial failure, it has been the practice, from a very early period, to turn inverted arches (see fig. 615.) to catch on their springing the weight to be provided against, by which means such weight is equally distributed throughout the length of the foundation. Standing thus," says our master Alberti, "they (the columns or weights) will be less apt to force their way into the earth in any one place, the weight being counterpoised and thrown equally on both sides on the props of the arches. how apt columns are to drive into the ground, by means of the great pressure of the weight laid on them, is manifest from that corner of the noble temple of Vespasian that stands to the north-west; for, being desirous to leave the public way, which was interrupted by that angle, a free and open passage underneath, they broke the area of their platform, and turned an arch against the wall, leaving that corner as a sort of pilaster on the other side of the passage, and fortifying it as well as possible, with stout work, and with the assistance of a buttress. Yet this, at last, by the vast weight of so great a building, and the giving way of the earth, became ruinous."

Fig. 615.

And

1886. It is most important, when the walls are raised on the foundations, and brought up a little above the level of the earth, to take care that the earth, most especially if moist, should not lie against them; for if walls, before they are dry and settled, imbibe moisture, they rarely ever part with it, and thence gradually impart rot to the timbers throughout the house. In all buildings, it is an object to have a second thin wall outside the basement walls, so as to leave between it and them a cavity for the circulation of the air, such cavity being technically called an air-drain. This is in all cases desirable, but in moist and loose soils it is essentially necessary for the durability of the building, as well as for the health of those who are to dwell in it.

1887. We, perhaps, might have more properly spoken first of the subject of drainage and sewers, whereof it now becomes our duty to give some information, inasmuch as before a brick or stone of any building be laid, the architect neglects his duty if he has not provided for perfect drainage in the lowest parts of the structure. This must not be by the aid of a small stagnant tank, called a cesspool, often the cause of much disease in a family; but by means of a drain into some running stream at a distance from the building, or, if that be not practicable, into some far removed pond, whose exhalations shall not be blown by the prevalent winds of the spot back upon the place where they were generated, in a different form. Neither does the health alone of the family whose comfort is to be provided for, demand this consideration of drainage; for the durability of the structure is quite as much involved in good drainage as is the health of the family whose dwelling-place the house is to become: hence we are the more earnest in pressing the point. In cities, the architect cannot always accomplish this most important object to the extent of his desire; but in the country, he is unpardonable if he neglect so necessary a provision. In London and its suburbs, the laying down of efficient sewage has been gradually proceeding; and in half a century, should it proceed at the same rate that it has during the last fifteen years, we apprehend that there will be no city in Europe possessing so good a drainage.

1888. The main drain necessary for the service of the largest house (we suppose the case of one in the country), if the fall given it be even but moderate, requires no very large dimensions. When we recollect that a small river, draining a very considerable tract of country, is often in its section only 8, 9, or 10 feet superficial, it will easily be conceived that the surplus from, and rain water falling on a mansion, is a quantity, even at the most pressing times, requiring little area of discharge to free the place from damp. There are few cases in which the largest mansion would require, for its main branch of drainage, an area of more than 5 feet, which would be given by a sewer or drain 2 ft. by 2 ft. 6 in., supposing its section to be that of a parallelogram; but of course, where the fall permits, there is no objection to larger dimensions. It will be hardly necessary to recommend that drains should, as well for their durability as on other accounts, be constructed with curved bottoms. It is surprising that some (at least one) commissions of sewers about the metropolis should still persist in constructing their principal drains with flat bottoms, offering an additional impediment, by increased friction, to the more rapid discharge of the water. Thus, for instance, let us take the lower parts of two drains whose running depth of water is 1 foot, one whereof is formed with a semicircular bottom, 2 feet wide; the area of the column of water will therefore be 1·5708, and the length of the half curve will be 3·1416. To obtain, with one foot depth of water, the same area in a drain whose bottom is flat and

sides upright, we must have the width 1.5708, and the sum of the three sides touched by the water will be 3.5708. Then 3·5708-3·1416=4292 represents roughly the difference of friction or impediment in favour of the semicircular bottom in the case stated, nearly of the power being lost by the use of a flat bottom.

SECT. II.

BRICKLAYING AND TILING.

1889. Bricklaying, or the art of building with bricks, or of uniting them by cement or mortar into various forms, includes, in the metropolis, and mostly in the provinces, the business of walling, tiling, and paving with bricks or tiles, and sometimes plastering; but this last is rarely, if ever, undertaken by the London bricklayer; though in the country the trades of bricklaying and plastering are usually united, and not unfrequently that of masonry also. The materials used have been described in a previous part of the work, to which the reader is referred (1811. et seq.).

1890. The tools used by the bricklayer, who has always an attendant labourer to supply him with bricks, mortar, &c., are-1. A brick trowel, for taking up and spreading the mortar, and also for cutting the bricks to any required length. 2. A hammer, for cutting holes and chases in brickwork. 3. The plumb rule, being a thin rule, 6 or 7 inches wide, with a line and plummet swinging in the middle of it, in order to ascertain that the walls are carried up perpendicularly. 4. The level, which is about 10 or 12 feet long, with a vertical rule attached to it, in which a line and plummet are suspended, the use whereof is to try the level of the walls at various stages of the building as it proceeds, and particularly at the window cills and wall plates. 5. The large square, for setting out right angles. 6. The rod, for measuring lengths, usually 5 or 10 feet long. 7. The jointing rule, about 8 or 10 feet long, as one or two bricklayers are to use it, and 4 inches broad, with which they run or mark the centre of each joint of the brickwork. 8. The jointer, which is of iron, shaped like the letter S. 9. The compasses, for traversing arches and vaults. 10. The raker, a piece of iron having two knees or angles, dividing it into three parts at right angles to each other, the two end parts being pointed and equally long, and standing upon contrary sides of the middle part. Its use is to rake out decayed mortar from the joints of old walls for the purpose of replacing it with new mortar, or, as it is called, pointing them. 11. The hod, which is a wooden trough shut close across at one extremity and open at the other. The sides consist of two boards at right angles to each other, from the meeting whereof a handle projects at right angles to their union. It is used by the labourer for conveying bricks and mortar to the bricklayer; for which purpose, when he has the latter office to perform, he strews dry sand on its inside, to prevent the mortar from sticking. 12. The line pins, which are of iron, for fastening and stretching the line at proper intervals of the wall, that each course may be kept straight in the face and level on the bed. The pins have a line attached to them of 60 ft. to each pin. 13. The rammer, used for trying the ground, as well as for beating it solid to the utmost degree of compression. 13. The iron crow and pick axe, for breaking and cutting through walls or moving heavy weights. 14. The grinding stone, for sharpening axes, hammers, and other tools. The following ten articles relate entirely to the preparation and cutting of guaged arches. 15. The banker, which is a bench from 6 to 12 ft. long, according to the number of workmen who are to work at it. It is 2 ft. 6 in. to 3 ft. wide, and about 2 ft. 8 in. high. Its use is for preparing the bricks for rubbed arches, and for other guaged work. 16. The camber slip, a piece of wood usually about half an inch thick, with at least one curved edge, rising about 1 inch in 6 feet, for drawing the sofite line of straight arches. When the other edge is curved, it rises about half that of the other, that is, about half an inch in 6 feet, for the purpose of drawing the upper line of the arch, so as to prevent it becoming hollow by the settling of the arch. The upper edge is not always cambered, many preferring it straight. The slip being sufficiently long, it answers the width of many openings; and when the bricklayer has drawn his arch, he delivers it to the carpenter to prepare the centre for it. 17. The rubbing stone. This is of a cylindrical form, about 20 inches diameter, but may be less. It is fixed at one end of the banker, upon a bed of mortar. After the bricks for the guaged work have been rough-shaped by the axe, they are rubbed smooth on the rubbing stone. The headers and stretchers, in return, which are not axed, are called rubbed returns and rubbed headers and stretchers. 18. The bedding stone, which is a straight piece of marble 18 or 20 inches in length, of any thickness, and about 8 or 10 inches wide. It is used to try the rubbed side of a brick, which must be first squared to prove whether its surface be straight, so as to fit it upon the leading skew back, or leading end of the arch. 19. The square, for trying the bedding of the bricks, and squaring the sofites across the breadth of the bricks. bevel, for drawing the sofite line on the face of the bricks.

20. The 21. The mould, for forming the

face and back of the brick, in order to reduce it in thickness to its proper taper, one edge of the mould being brought close to the bed of the brick when squared. The mould has a notch for every course of the arch. 22. The scribe, a spike or large nail, ground to a sharp point, to mark the bricks on the face and back by the tapering edges of the mould, for the purpose of cutting them. 23. The tin saw used for cutting the sofite lines about one eighth of an inch deep, first by the edge of the level on the face of the brick, then by the edge of the square on the bed of the brick, in order to enter the brick axe, and to keep the brick from spalting. The saw is also used for cutting the sofite through its breadth in the direction of the tapering lines, drawn upon the face and back edge of the brick; but the cutting is always made deeper on the face and back of the brick than in the middle of its thickness, for the above-mentioned purpose of entering the axe. The saw is also used for cutting the false joints of headers and stretchers. 24. The brick axe, for axing off the sofites of bricks to the saw cuttings, and the sides to the lines drawn by the scribes. The bricks being always rubbed smooth after axing, the more truly they are axed the less labour will be requisite in rubbing them. 25. The templet. This is used for taking the length of the stretcher and width of the header. 26. The chopping block, for reducing the bricks to their intended size and form by axing them. It is made of any piece of wood that comes to hand, from 6 to 8 inches square, and generally supported upon two 14-inch brick piers, if only two men work at it; but if four men, the chopping-block must be lengthened and supported by three piers, and so on according to the number employed at it. It is about 2 ft. 3 in. in height. 27. The float-stone, which is used for rubbing curved work to a smooth surface, such as the cylindrical backs and spherical heads of niches, to take out the axe marks. It is, before application to them, made of a form reversed to the surface whereon it is applied, so as to coincide with it as nearly as possible in finishing.

1891. Before adverting to the bond, as it is technically called, of brick walling, which is the form of connection of the bricks with each other, we will stop to observe, that in working walls, not more than 4 or 5 feet should be brought up at a time; for as, in setting, the mortar shrinks and a general subsidence takes place, the part first brought up, if too large in quantity, will have come to its bearing before the adjacent parts are brought up, and thus fissures in the work and unequal settlements will take place. In carrying up any particular part above another, it should always be regularly sloped back to receive the adjoining parts to the right and to the left. On no account should any part of a wall be carried higher than one scaffold, except for some very urgent object.

1892. Previous to the reign of William and Mary, all the brick buildings in this island were constructed in what is called English bond; and subsequent to the reign in question, when, in building as in many other cases, Dutch fashions were introduced, we regret to say, much to the injury of our houses' strength, the workmen have become so infatuated with what is called Flemish bond, that it is difficult to drive them out of it. To the introduction of the latter has been attributed (in many cases with justice) the splitting of walls into two thicknesses; to prevent which, expedients have been adopted, which would be altogether unnecessary if a return to the general use of English bond could be esta blished.

1893. In chap. i. sect x. of this book (1550. et seq.) we have spoken generally on walls; our observations here, therefore, in respect of them, will be confined to brick walls and their bond.

which (except at the quoins) In brick walling, and indeed

but

We are

1894. English bond is that disposition of bricks in a wall in the courses are alternately composed of headers and stretchers. in stone walling also, a course means the horizontal layer of bricks or stones whereof the wall is composed, being contained between two faces parallel to the horizon, and terminated on each side by the vertical face of the wall. The mass also formed by brick or stones in an arch are also termed courses, receive the name of concentric courses. The term header is applied to a brick or stone whose small head or end is seen in the external face of the wall; and that of stretcher, to a brick or stone whose length is parallel to the face of the wall. therefore to understand by English bond, a continuation either of header or stretcher, continued throughout in the same course or horizontal layer, and hence we have described it as consisting of alternate layers of headers and stretchers (fig. 616.), the former serving to bind the wall together in a transverse direction or widthwise, and thus prevent its splitting, whilst the latter binds it lengthwise, or in a longitudinal direction. None but the English bond prevents the former occurrence, as work executed in this way, when so undermined as to cause a fracture, separates, but rarely breaks through the solid brick, as if the wall were composed of one entire piece.

1895. The ancient Roman brickwork was executed on this

ELEVATION.

Fig. 616.

PIAN.

principle; and its extraordinary durability is as much to be attributed to that sort of work being used for bonding it together, as to its extraordinary thickness.

1896. In this, as well as Flemish bond, to which we shall presently come, it will be observed, that the length of a brick being but 9 inches, and its width 43 inches, in order to break the joints (that is, that one joint may not come over another), it becomes necessary near the angles to interpose a quarter brick or bat, a, called a queen closer, in order to preserve the continuity of the bond in the heading course. The bond, however, may equally be preserved by a three-quarter bat at the angle in the stretching course, in which case this last bat is called a king closer. In each case an horizontal lap of two inches and a half is left for the next header. The figure above given is that of a two-brick or 18-inch wall, but the student will have no difficulty in drawing, on due consideration of it, a diagram of the bond for any other thickness of wall; recollecting, first, that each course is formed either of headers or stretchers. Secondly, that every brick in the same course and on the same face of the wall must be laid in the same direction, and that in no instance is a brick to be placed with its whole length against the side of another, but in such way that the end of one may reach to the middle of the others that lie contiguous to it, excepting in the outside of the stretching course, where three-quarter bricks, or king closers, will of course be necessary at the ends, to prevent a continued upright joint in the face of the work. Thirdly, that a wall crossing at right angles with another will have all the bricks of the same level course in the same parallel direction, whereby the angles will be completely bonded. We shall close these observations with a recommendation to the young architect, founded on our own experience, on no account, in any building where soundness of work is a desideratum, to permit any other than English bond to be executed under his superintendence.

1897. Flemish bond is that wherein the same course consists alternately of headers and stretchers, which, in appearance, some may fancy superior to that just described. Such is not our opinion. We think that the semblance of strength has much to do with that of beauty in architecture. But there is in the sufferance of Flemish bond a vice by which strength is altogether lost sight of, which we shall now describe. It was formerly, though now partially, the practice to face the front walls of houses with guaged or rubbed bricks, or with at least a superior species of brick, as the malm stock; in the former cases, the bricks being reduced in thickness, and laid with a flat thin joint frequently, what the workmen call a putty joint, for the external face, the outer and inner work of the same courses in the same wall, not corresponding in height, could not be bonded together except where occasionally the courses fell even, where a header was introduced from the outside to tie or bond the front to the internal work. Hence, as the work would not admit of this, except occasionally, from the want of correspondence between the interior and exterior courses, the headers would be introduced only where such correspondence took place, which would only occur in a height of several courses. Thus a wall two bricks in thickness, if faced on both sides, was very little indeed better than three thin walls, the two outer half a brick thick, and the middle one a brick or 9 inches thick. Bricklayers having little regard for their character will, if not prevented by the architect, not only practise this expedient, but will also, unless vigilantly watched, when a better sort of brick is used for the facing, cut the headers in half to effect a paltry saving of the better material. In walls of one brick and a half in thickness, the strength of the wall is not diminished by the use of Flemish bond so much as in those of greater thickness, as may be seen by the diagram (fig. 617.). Many expedients have been invented to obviate the inconveniences of Flemish bond; but we think it rather useful to omit them, lest we should be considered as parties to a toleration of its use, for the continuation whereof no substantial reason can be assigned. As we have before observed, all that can be alleged in its favour is a fancy in respect of its appearance: but were the English mode executed with the same attention and neatness bestowed on the Flemish method, we should say it was equally beautiful; and therefore we shall thus close our notice of it.

ELEVATION.

Fig. 617

1898. The two principal matters to be considered in brick walling are, first, that the wall be as strong as possible in the direction of its length. Secondly, that it be so connected in its transverse direction that it should not be capable of separating in thicknesses. To produce the first, independent of the extraneous aid of bond timbers, plates, &c., it is clear that the method which affords the greatest quantity of longitudinal bond is to be preferred, as in the transverse direction is that which gives the greatest quantity of bond in direction of the thickness. We will, to exemplify this, take a piece of walling 4 bricks long, 4 bricks high, and 2 bricks thick, of English bond: in this will occur 32 stretchers, 24 headers, and 16 half headers to break the joint, or prevent one joint falling over another. Now, in an equal piece of walling constructed in Flemish bond, there will occur only 20

stretchers and 42 headers; from which the great superiority of English bond may be at once inferred.

Some

1899. Bond timber should be used in pieces as long as circumstances will admit. prefer its being laid in the centre of the wall, in which case, when dressings of wood are required on the interior face, wooden plugs must be provided to nail them to, which are not wanted where the bond timber is laid flush with the inner face of the wall.

1900. It will scarcely be necessary to inculcate the propriety of the mortar beds being as thin as possible. In good sound work they ought not to rise more that 11 inches. The mortar or cement should be such as will quickly set, to prevent the superincumbent weight pressing the joints closer, and thereby causing settlements which, even with the greatest care, often take place unequally. As often as it is conjectured, from the nature of the soil, or from the foundation being partly new and partly old, that the work will not come to its bearing equally, it is better to carry up the suspected parts separately, and to leave at their ends what are called toothings, by which junctions may be made when the weaker parts have come to their regular sound bearing. The thickness of walls has furnished the subject of previous pages; we shall therefore only add, that too much care cannot be bestowed on strengthening all angles as much as possible, and well connecting the return of one wall into another; that piers or pilasters are exceedingly useful in strengthening walls, inasmuch as they act by increasing the base whereon the whole stands; and, lastly, that in carrying up walls to any considerable height, it is usual to diminish their thickness by sets off as they rise. In houses, above the ground-floor, the sets off are usually made on the inside, having the outside in one face; but, if it be possible, it is better to set off equally from both faces, because of the better balance afforded..

1901. A bricklayer, with the assistance of one labourer, will in one day lay about 1000 bricks in common walling; hence he would complete a rod of brickwork in four days and a half, its area being 2721 ft. superficial of the thickness of one brick and a half. When, however, there are many apertures or other interruptions to his work, he will be proportionably longer time over it. The weight of a rod of brickwork is about thirteen tons. Generally it may be taken as consisting of 4500 stock bricks, allowing for waste, 27 bushels of chalk lime, and 3 single loads of drift sand, or 18 bushels of stone lime and 31 single loads of sand. In cement, of 36 bushels, and the same quantity of sharp sand.

1902. Bricknogging is a method of constructing a wall with a row of posts or quarters 3 feet apart, whose intervals are filled up with brickwork. It is rarely more than the width of a brick in thickness, and the bricks and timbers on the faces are flush. It should never be used where thickness can be obtained for a nine-inch wall.

1903. Groined arches. A groin is the angular curve formed by the intersection of two semi-cylinders or arches. When groins are formed of cones they are called conic groins; but our business here is with the more simple groins that occur in using brick arches. The centering for raising them belongs to the section Carpentry, to which the reader must refer. The turning a simple arch on a centre only requires care to keep the courses as close as possible, and to avoid the use of much mortar on the inner part of the joints. In executing a brick groin, the difficulty arises from the peculiar mode of making proper bond at the intersection of the two circles as they gradually rise to the crown, where they form an exact point. In the meeting or intersecting of these angles, the inner rib should be perfectly straight and perpendicular to a diagonal line drawn on the plan. After the centres are set, the application of the brick to the angle will immediately show in what direction it is to be cut. With respect

to the sides, they are turned as for common cylindric vaults. The late Mr. George Tappen, an architect of great practical skill, introduced a method of constructing groins rising from octangular piers. which had the advantage of not only imparting strength to the angle, which in the common groin is extremely deficient, but of increasing the space for the stowage or removal of goods, and further, of strengthening the angles of the groin in this construction by carrying the band round the diagonals (fig. 618.) of equal breadth, and thus affording better bond to the bricks.

1904. Many ornamental brick cornices may be formed by but little cutting, and changing the position of the bricks employed, and several, indeed, without cutting, by chamfering only.

Fig. 613.