* *. PARA RAILWAY CONSTRUCTION. FIRST SERIES. BY W. D. HASKOLL. 2.VOLS. PRICE £2.12.6 ... 1 J NajkaardapÀM GEN phwehalení inelinhei ms bi : : BTBATSFORD, ARCHITECTURAL & ENGINEERING COBOOKSELLER 52. High Holborn. LONDON, W.C * Cikalle TRANSPORT THE JERSITY ION UP C O ܗ GERMA KRAKEN the water test or to the fa the jou get 1 fevereir HEA いめ​!! MY DA RAILWAY CONSTRUCTION : FROM THE SETTING OUT OF THE CENTRE LINE TO THE COMPLETION OF THE WORKS; CONTAINING INSTRUCTIONS FOR RANGING CURVES AND SETTING OUT LINES AND LEVELS In Earthworks, Permanent Way, Bridges & Viaducts ON THE SQUARE, ON THE SKEW, AND ON CURVES. A TREATISE ON TAKING BORINGS; WITH PRACTICAL RULES FOR DESIGNING WORKS, AND GETTING OUT WORKING DRAWINGS illiam OF Masonry and Brickwork, Timber, Wrought Iron and Cast Iron. AND EXAMPLES OF SPECIFICATIONS, AND TABLES FOR EARTHWORK. ILLUSTRATED BY 250 PLATES & DIAGRAMS OF EXECUTED WORKS. BY W DAVIS HASKOLL, CIVIL ENGINEER. ** VOL. II. LE LONDON: ATCHLEY & CO., 106, GREAT RUSSELL STREET, BEDFORD SQUARE. [The Right of Translation is reserved.] ཀ་ DR 1 Transportation ibrary TF 2.00 H37 V. 2 BRICK AND STONE BRIDGES, 201 Transport. CHAPTER IX. PART I. BRIDGES OF STONE AND BRICKWORK, RETAINING WALLS, MANAGE. MENT OF MASONRY AND BRICKWORK, TECHNICAL TERMS, CEN- TRES FOR RAILWAY ARCHES. - THE principal works of construction on a railway, besides tunnels, consist of bridges and viaducts of brick, stone, wood, or iron, aqueduct bridges, culverts, and retaining walls. BRICK AND STONE BRIDGES.—THE ARCH. In the following pages these will be treated of consecutively, not as regards those gigantic works which are the wonders of the age, and the description of one of which would alone require a large volume, but as to the more ordinary works found on railways. The spans of railway arches are seldom of any considerable dimensions, and rarely exceed some 30 or 40 feet on the square. In spanning some very wide turnpike roads, a river, or a canal, these dimensions are occasionally exceeded, as they will be also in the arches of lofty viaducts; but in these times the Engineer must take considerably more pains to avoid such works than he would have to take in design- ing or carrying them into execution. The following table will give the depths at the crown of the arch P 202 BRICK AND STONE BRIDGES. for the following spans of brick arches under a railway, according to general practice, when equally extradosed:- Span in Feet. 15 20 30 40 50 60 Segmental arch, of which the rise is not less than 1th of the span. 1' 6" 1 6 1 10/1/20 2 3 2 7/12/20 3 0 ~ Elliptical arch, of which the rise is not less than 3rd of the span. 1′ 6″ 1 6 1 10/1/10 2 7/1/2 3 0 3 4-1-20 - For bridges under roads these dimen- sions may be a brick less. 1 The function of the arch at the crown is, theoretically, resistance to crushing, and as far as this only is concerned, 13 feet in depth, for a span of 15 feet, is too great. But we have to consider not merely a moderate vibration, but a very sensible shaking, to resist the effects of which, in such materials as masonry and brickwork, some mass is required. For block in course arches we should take 2 feet instead of 1′ 10″, and 2′ 6″ instead of 2′ 3″, unless for the very best material and workmanship. It has been ascertained by experiment that by using a segmental arch instead of a semicircular one we get free of two points of rupture, and the rise in this segment is about one-third of the span (Fig. 1). In the case of an arch with piers, we may even make the rise one- fourth and one-fifth of the span, if we make the arch unequally extra- dosed. This raises the height of the piers; but economy of material is effected in these by the introduction of jack-arches. In the case of a bridge, under a heavy embankment, we may make use of a tunnel-shaped arch. The theory of the arch has been treated of by one of our greatest analysts, Professor Moseley, in a most scientific and elegant manner, and with the greatest mathematical skill, in his Mechanical Principles of Engineering, and in the sixth volume of the Cambridge Philosophical Transactions. Although the calculations involved are, as the Professor BRICK AND STONE BRIDGES. 203 observes, laborious, to these works the reader is referred for the com- plete mathematical study of the subject. There will be merely a few geometrical applications given in these pages, but such, as being based on this theory, will not be without practical use. If we imagine three stones, A, B, C, (Fig. 1) piled one upon the other, without cement, and without any other pressure than their own weight, and more or less overhanging each other, it will be evident that this pressure, whatever it may be, must keep them in place, or else C would turn over at a, and B would slide upon the bed A, and the medium by which the pressure acts is friction. The importance of friction in everyday occurrences is brought forward in the following words by Professor Moseley :-" Were there no friction, it would be impossible for a man to move from any position in which he might be placed, without the aid of some fixed obstacle, by means of which he might push himself forward. And were there no horizontal power of resistance in the ground on which he treads, to destroy the forward motion which he gives himself at every step, he would retain that motion until some obstacle interposed to destroy it." Equilibrium will be maintained in two bodies in contact, acted upon by any number of forces, if the resultants of the forces be equal and in opposite indirection, and if they pass through the area contained within the extreme points of contact of the two bodies; further, they must not make a greater angle with a perpendicular to the plane of contact than the "limiting angle of resistance." If G (Fig 3) represents the force of gravity, or weight of a stone, H the horizontal thrust, and R the resultant of these two forces, then, in order that this stone, lying merely in contact upon the under one, be kept at rest, the direction of the resultant R must cut the line of contact AB, or the upper stone would roll upon the lower; on A, as centre, if the resultant fall inside of the arch; and on B, as a centre, if the resultant fall outside; or, in other words, if the weight of the stone be so great as to overcome the horizontal force H, then the stone will roll over at A; and if H be so great as to overcome G, then the stone will roll over at B. But, besides passing through the surface of contact A B, the resultant must not be inclined to the perpendicular P P', at a greater angle than the angle of friction, or limiting angle of resistance. P 2 204 BRICK AND STONE BRIDGES. But if we place the stones so that the lines passing through their centres. of gravity, instead of passing also through the underlying line of contact, should pass without it, as we do in the arch, by making the beds radiate, or simply by making the stones overlap, or overhang each other, we shall find that after raising up a few stones, the upper ones will roll over, unless supported by an extraneous force. In an arch this extraneous force is applied by the opposite segment of the arch. An equilibrated arch, then, is a system of stones in contact, so arranged and of such dimensions, that the resultants of all the forces acting upon it shall fall within the curved lines bounding the arch, and not make greater angles with the perpendiculars to the beds than the limiting angle of resistance due to the material of which the arch is composed. Thus, in Fig. 4, after placing the third arch-stone, further progress must cease, unless some opposing force be called into action. Let this force be called P. In the case of the arch of a bridge, this force would be offered by the opposite half segment, which would be exactly in the same condition, and as we proceed with this subject P will designate this opposite half segment of an arch. In order that the fifth stone retain its place on the fourth, the forces passing through them must have their resultants in opposite directions, and equal and acting through the same point; this point must be in the line of contact, and the angle made by the resultants, with a perpendicular to IK, must not exceed the limiting angle of resistance. Let Pp³, the line of direction of the force P, be produced to meet the vertical line O G³, which passes through the centre of gravity of the arch-stone; then the direction of a force acting with P to keep the arch-stone from falling by its weight (represented in direction and position by the line O G³), must pass through the point O³, where these two meet, and have the direction and amount of their resultant by the known principles of forces in equilibrio. Let Op be this line; produce it to cut the vertical O'G'; then, in a similar manner, O¹ p³, which represents the third force necessary for equilibrium, must be a line cutting the vertical in the point O', and having the direction of the resultant of two forces, the one acting through p', and the other BRICK AND STONE BRIDGES. 205 that of the weight acting through the vertical line O' G'. This force must also cut the surface of contact, G H, and make an angle with a perpendicular to the surface G H not greater than the limiting angle of resistance. It can only be supplied by the resistance or reaction on the surface G H. The forces in action on these two arch-stones are, then, on L MIK, the force P, and the weight of the stone represented by G³; on the stone IK G H the reaction or resistance afforded by the mass below, represented by p³, and the weight of the stone by G', and their resul- tants, p¹ O', and p' O', which must be equal and act in opposite directions. in order that equilibrium be maintained. The reactionary forces, severally and respectively, balance the two forces opposed to them; they therefore represent the stress or thrust of the superincumbent voussoirs at the joints, the resultant or re- action at each joint being the new force impressing the stone below it. It is plain, then, that the last resultant, being the reaction on the surface of the springer A B, will be compounded of the resultants and weights of all the stones above it, together with the force P, afforded by the reaction of the opposite half segment. This resultant, then, will represent the direction, and where it cuts the line, A B, the point of application of the stress or thrust of the whole arch upon the abutment. It must, of course, cut the surface A B within its boun- daries, and not make a greater angle with a perpendicular to that surface than the limiting angle of resistance, or equilibrium will not be maintained. - The forces above-mentioned severally and respectively represent the thrust of the superincumbent voussoirs at the several joints, the resultant of the vertical and horizontal forces at each joint being the new force impressing the stone below it. The last resultant at the springing will be compounded of the resultants of the weights of all the stones above it, together with the force P, by which letter we still designate the resistance from the opposite segment of the arch. To make what follows more clear, it is desirable to give a demon- stration of forces acting through a point and being in equilibrium, which will be used in the sequel. Let the lines ab, bc, Fig. 5, 206 BRICK AND STONE BRIDGES. represent the direction and amount of two forces acting through a given point; then, if the points a c be joined, the line a c will be equal to the resultant of these forces both in direction and amount. Make A B perpendicular to a b, and BC to bc, and AC to a c. Let these lines intersect at A, B, C; then will they be proportional to the lines to which they have been drawn perpendicular. For in the triangle A ca, the exterior angle, a c C, is equal to the sum of the two interior and opposite angles ca A, c A a. And because a c C is a right angle by construction, then A ac+CA c is equal also to a right angle. But the angle ba A, which is made up of the two angles bac, ca A, is also a right angle; therefore, as the angle ca A is common to both, the angle bac is equal to the angle B A C. And the two triangles are similar, and the lines opposite the equal angles are proportional. Therefore, if the three lines of any triangle represent in amount and direction three forces in equilibrio, then three lines drawn perpendicular to these, and produced until they meet, will also represent in amount the several forces to whose directions they are perpendicular. Let A DEB (Fig. 6) represent the half of a semicircular arch of 30 feet span, having a thickness of 2 feet at the crown. Let the scale be 4 feet to 1 inch, and let the semi-arch be composed of sixteen arch- stones, besides the half key-stone. We will proceed to consider the backing required for such an arch, on the hypothesis that the arch- stones are perfectly smooth, without cement and free from friction. Let P be the horizontal thrust from the opposite half segment. Join 1 C, 2 C, 3 C, &c. By the scale given, the half key-stone will contain 1.75 square feet of surface; and as the material is all the same, and the arch-stones of equal depth, we may assume this as the measure of weight of the half key-stone. With a scale of 10 feet to 1 inch, a horizontal line drawn through the point K will have the portion H G, intercepted between the two radiating lines B C, 1 C; equal to 1.75. This line, then, we will take as a scale for the weights of the backing required. Now, in the triangle KGC we have the line KG, being horizontal, perpen- dicular to the direction of gravity acting upon the key-stone through its centre of gravity, and also representing in magnitude that force, or 207 BRICK AND STONE BRIDGES. the weight of 1.75 square feet. If we assume the line K C, which is perpendicular to the direction of the horizontal force P, to represent it also in magnitude, then G C must also represent the resultant of these two forces on the half key-stone in magnitude, inasmuch as it is per- pendicular to it in direction; for the direction of the resultant of these two forces must be perpendicular to the face of the arch joints, and therefore to CG, otherwise no equilibrium would exist, as by the hypothesis there is no friction. The three lines KG, K C, and G C, being therefore respectively perpendicular to the three forces acting on the key-stone, and of them K G, being proportional to the force of gravity in magnitude, the other two will to the same scale represent the value of the horizontal force P, and the reaction (which is the resultant of the other two-namely, gravity and the horizontal force P) on the first joint 1 C 1'. The forces in action on the mass 1, 2, are the reaction last formed acting in the direction Cg-the force of gravity, or weight of the mass, acting through the centre of gravity in a vertical direction, and the resultant of these two, or the reaction necessary to keep the structure in equilibrio afforded by the surface of the joint 2. This last must also by the hypothesis be perpendicular to the line 2 C; and they must all three cut each other in the same point. Now, in the triangle GIC, we have G C representing in magnitude the thrust on the joint 1, and being perpendicular to it in direction; the line I C perpendicular to the direction of the reaction on the joint 2; and the line G I perpendicular to the direction of the force of gravity; but in any triangle, if the sides be taken to represent the value and direc- tion of three forces passing through the same point, these three forces are necessarily in equilibrio; therefore the lines G I, G C, IC, represent three forces in equilibrio. One of these lines, GC, represents the thrusts on the joint 1, in magnitude, and is perpendicular to it in direction; the other two lines are respectively perpendicular to the direction of the other two forces acting on the mass, 1, 2. Conse- quently they will respectively represent them in magnitude; also by the proposition given above, GI, by scale, will be found to measure 6.2, which is about the weight of two arch-stones; as far as 2, there- fore, no backing will be required. In a similar manner, in triangle IK C, IC will represent the thrust on joint 2, acting in the direction 釘 ​208 BRICK AND STONE BRIDGES. • g'g'; IK, the necessary weight, acting through the centre of gravity of the mass, comprising the two arch-stones and the backing; and K C the reaction on the joint 3. By scale, IK measures 6.7 feet; a small portion of backing, 0.5 feet is, therefore, required to maintain equili- brium on the conditions stated. It will be seen that the line of thrust which before kept to the same distance from the centre, C, throughout the first two arch-stones, where no backing was required in this pair, approaches the extrados of the arch. The reason of this is, that the centre of gravity of the mass, 2 2′ 3′ 7, is not the same as that of the arch-stones, which does not sensibly differ from their centre, but has moved more towards the abutment; the vertical line passing through this, which the directions of the two forces g'g', 'g, must intersect in the same point, has there- fore moved a little in the direction from C to D, and consequently the line g'g cuts the joint 3 3", a little higher up than its centre. It will readily appear, from a similar course of reasoning to that given in the instances of the masses 1 2, and 2 3, that the segments of the horizontal line, which we have taken for a scale, cut off by the intersection of the radii produced, will represent the requisite weight, or superficial area, and consequent amount of backing necessary to be placed vertically over the respective portions of the arch-ring cut off by these radii, in order that equilibrium be maintained. The portion KL measures 8.2 feet; taking away the area of the arch-stones, 6.2 feet, there will remain 2 feet to be disposed between the vertical lines, 7 3, m 4; 10.6 6.2 4.4 feet between the verticals, m 4, n 5; and 16.06.2 9.8 feet between the verticals, n 5, r 6. The inter- section of the radius, E 7, with the horizontal line is not within the limits of the diagram; it, however, cuts off a portion measuring 30 feet, from which 6.2 feet being subtracted, 23.8 feet remain to be disposed of in the form of backing between the r 6, s 7. This large mass causes the extrados to assume a most unmanageable form; and, in the case of the lower arch-stones, the evil is immensely increased-indeed, to produce a line of thrust at right angles to the face of the springing stone, nothing short of backing carried up to an infinite height will suffice. It has, at an early part of this chapter, been observed that the - g = BRICK AND STONE BRIDGES. 209 : resultant of one set of forces must not cut the plane of contact of the two bodies, so as to make a greater angle with a perpendicular to that plane than the limiting angle of resistance. In the foregoing case, the resultant has been drawn so as to coincide with the perpendicular, on the supposition that the angle of resistance is equal to nothing, and consequently that there is no friction, a condition which, in practice, never exists. Numerous experiments show that it always acts in a direction parallel to the surfaces in contact, and is for the same descrip- tion of surface, the same fraction of the impressing force, very nearly, whatever the amount of that force may be, and whatever the extent of the surfaces in contact. For our purpose, we may assume this law to hold good for every pressure, the variations being so small as to be of no moment. This fraction has been called the co-efficient of friction. If two stones of granite be pressed together, the co-efficient of friction is found by experiment to be, and for sandstone. The limiting angle of resistance has this co-efficient for its weight, and this angle we will make use of instead of the co-efficient, as being more convenient for drawing, and because it is the direct result of experiments. These show that this angle varies from 25° to 40°. With fresh and finely- ground mortar, the stones move at a less angle than when no mortar is applied. In stone bridges it will be safest to assume the angle of 26° for the limiting angle of resistance, although the line of pressure very rarely makes so large an angle with the perpendicular even as this, many causes acting to make it fall rather within than without this limit. When the line of pressure, however, cuts the abutment, it has a tendency, especially where the load is great, to approach this angle, and even exceed it, unless proper means be taken to divert it downwards. There is one condition which always controls and defines the exact position the line of thrust will take. This is the universal prevalence throughout Nature of the law of the economy of forces, or the principle of least resistance, or in other words, that Nature performs her work with the least necessary amount of labour. This principle, which is almost self-evident, was first discovered by Moseley, and he has given the following demonstration:- "Let us suppose the forces of a system, which are not resistances, to be represented by the letter A, and the resistances by B; also let 210 BRICK AND STONE BRIDGES. any other system of forces which may be made to replace the forces B, and sustain A, be represented by C. "Suppose the system B to be replaced by C, then it is apparent that each force of the system C is equal to the pressure propagated to its point of application by the forces of the system A; or it is equal to that pressure, together with the pressure so propagated to it by the other forces of the system C. In the former case it is identical with one of the resistances of the system B; in the latter case it is greater than it. "Hence, therefore, it appears that each force of the system B is a minimum, subject to the conditions imposed by the equilibrium of the whole." Of any number of lines of resistance which may be drawn within the boundaries of an arch-ring, this principle enables us to perceive that one which the pressures acting upon the arch would naturally generate. In Fig. 7, let A, B, C, D, represent the half of a segmental arch, of 30 feet span and 9 feet rise, the thickness of the ring being 2 feet. Now, if this semi-arch were unsupported, it would turn on the point C, and fall. The force by which this is prevented we have called P. Let us suppose P to be removed, and this force replaced by a fixed and immovable surface, A B; it is obvious that the reaction on this plane will be the smallest possible in amount consistent with the conditions of equilibrium; that is, the resultant of all the resistances, which we call P, will be a minimum. There are then two forces acting upon the mass A, B, C, D-the weight W, acting vertically in a line through the centre of gravity, and the force P; and these two are in equilibrium, or the moment of W round C, as a centre, is equal to the moment of P. Now, the moment of W is made up of the weight of the semi-arch, multiplied into the distance G, C: both these are constant quantities, and the moment of P is made up of the force P, multiplied into C, F, both variable within certain limits. In order, then, that the force P be the least possible, the distance C, F, must be the greatest possible; in other words, the point of application of the force P must be as near as possible to the extrados of the arch at the crown. The line of thrust BRICK AND STONE BRIDGES. 211 must also touch the intrados of the arch at the haunches; for in this place all arches have been observed to fail. The mode of operation of the forces tending to cause the failure of an arch is this-first, the edges of the arch-stones splinter off at some distance on each side of the key-stone, the crown then sinks a little, and the haunches rise, the lower part of the arch turns outward, and the portion above the haunches falls inwards, dividing at the key-stone into two parts. Before the arch completely falls, it is mostly observed that, for a short time, the key-stone hangs by its upper corners, the joints being open below a perceptible distance; and, at the haunches, the joints are seen simultaneously to open above. This is precisely in accordance with the position of the point of application of the resistance P, which we have deduced from the principle of least resistance. The force afforded by the resistance of the opposite semi-arch acting through the key-stone, and pressing upon the joint 1 1' at the point c, would, as the lower part of the arch yields, keep the upper corners of the voussoirs in con- tact, whilst the changing form of the arch would cause the lower angles to separate. From the principle that the force P should be the least possible in amount, it follows that the line H, E, which is perpendicular to it in direction, and proportional to it in magnitude, should also be the least possible consistent with the maintenance of equilibrium; for it must be borne in mind that, as the force P is simply a resistance, it will vary in amount, according to the tendency of the semi-arch to fall inwards; and it will always equal the force due to that tendency, within the limits of the powers of resistance of the opposite semi- arch: so that the force P varies in amount and direction with every change in the load of the arch, inasmuch as such change of load will always affect this tendency to fall. Take the line H C for the scale line. To a scale of 10 feet to 1 inch, the weight of the semi key-stone will be represented by 1.5, equal to its area, which will cut off the portion Ha. Suppose the line a m, making with the radius 1, 1', O, an angle equal to the limiting angle of resistance, and giving the direction of the least possible force applied at C', at the key-stone, that would support the semi-arch; a perpendicular to the line a m, produced, would cut the joint 1, 1', making an angle the greatest possible, with the perpendicular 01 212 BRICK AND STONE BRIDGES. to its surface. Hm, therefore, is the least possible under the circum- stances. From a, on the scale line, set off equal distances, a b, bc, cd, &c., equal to 6.2, equal to the area of a pair of arch-stones; these divisions will represent the weight of the corresponding arch-stones, and ag will represent the weight of the semi-arch. Now, if lines were drawn through these points to m, they would be inclined to the respec- tive radii at angles too large for the limits of resistance of the surfaces of the joints, and therefore Hm is too small for the condition of equili brium of the whole mass. It has before been said that the line of thrust must touch the intrados at some point near the haunches; this is also a consequence of the principle of least resistance; for let us suppose, as before, that the support of the opposite semi-arch is taken away, and the arch revolves on the point C as a centre, then it will be seen, by inspection of the figure, that the resultant of the force P, and the weight of the semi-arch acting vertically through its centre of gravity in the line LG, must approach as near as possible to the point C; for, were the line LC to cut the joint CD near to D, it would show a tendency of the arch to revolve on D as a centre, and consequently that the horizontal force is more than sufficient for the mere support of the arch, and therefore larger than would be excited by the resistance of the opposite semi- arch; but the nearer the horizontal force approaches the minimum, the nearer the line of thrust will approach the point C. The line of thrust will, therefore, touch the intrados of the arch at some point near the haunches. It follows, as a consequence of this, that at the point in question the line of thrust corresponds in direction with the circle forming the intrados; it will, therefore, be perpendicular to the radius at that point. This furnishes a means of ascertaining by trial the least possible horizontal force necessary to maintain equilibrium; for, if we draw lines severally through the points a, b, c, d, e, &c., parallel to the respective radii 1 0, 2 0, 3 0, &c., we shall find that the line parallel to the radius D O cuts the vertical line A O, produced at the point E, higher up than any of the rest; that is, H E is the shortest line under the circumstances we can get. Now the line Eg being Now the line Eg being parallel to the joint CD, a perpendicular to Eg will correspond in direction with that of the circle B C at the point C-that is, it will be tangential to it. If BRICK AND STONE BRIDGES. 213 this tangent, then, cuts the vertical through the centre of gravity of the arch-ring L, G, in the point L, where it is cut by a line drawn perpen- dicular to the line a E, through the point C, it will follow that this line of thrust can be drawn without at any place cutting the boundaries of the arch-ring, and, consequently, that the horizontal force represented by the line H, E, is sufficient for the maintenance of equilibrium, it is also by construction the least possible in amount. Now, as far as this arch itself is concerned, it contains within its boundaries the line of resistance. But, to resist the loads of passing trains, or road traffic, such an arch without backing is insufficient. If we increase the length of HE, the line C F will approach more nearly to a horizontal direction, and consequently the system of lines. will move upwards and outwards, making the intersection of the last resultant Lg, with the joint CD, nearer to D. The horizontal force would be increased, and it would no longer be a minimum under the conditions imposed. Were the semi-arch continued downwards, so as to form the half of a semicircular arch, the lower part might not admit of the line of resistance shown to be drawn within the limits of the arch-ring. But in every instance the line having the least hori- zontal thrust will be found to be the one that exists. To assume a line of resistance with greater horizontal thrust than is sufficient for equilibrium renders necessary a larger amount of backing and greater width of abutment. To these subjects it will be time now to come. We may take the weight of a locomotive engine, for goods traffic, at 25 tons, exclusive of tender; to meet emergencies, and to be on the safe side of danger, for these calculations, take three times this weight, or 75 tons, which will, in fact, be equal to about six times the load dead weight likely to come on one point in a railway bridge; for although, in a six- wheeled locomotive, the driving-wheels will take more than a third of the load; yet, even if we allowed one-half, still we should not have more than 12.5 tons at one point on each rail. This gross load of 75 tons we will consider as over the crown of the arch at Fig. 8, where it would have the most influence. The arch itself is drawn to a scale of 4 feet to the inch. Whether on the longitudinal, or cross sleeper system, we shall be secure in considering this load as distributed over 9 feet in length, 214 BRICK AND STONE BRIDGES. which will give, say 8.5 tons per foot width of the arch. It is true the load due to the weight of puddle, ballast, and other portions of perma- nent way are to be considered; but we have allowed more than amply for all this, besides which these tend to distribute and equalize the load. In another chapter the reader will find the weights due to most kinds of stone, and also generally their crushing weights. Take the weight of the stone at 140 lbs. per cube foot, or 16 cube feet to the ton; then, 8.5 × 16 136 cube feet of stone, X equal to the load, in terms of the material of the arch. To this amount add that due to the key-stone, which, in this instance, taking the arch, as before, at 1 foot in width, will be 3 cube feet; and 136 + 3 2 of stone, applied at A, on each semi-arch. Mark this off to any convenient scale, say 20 feet to the inch, along the line A H, and in addition 36 feet, for the six pairs of arch-stones, each measuring 6 feet, and we have the whole amount of vertical force acting on the arch, on the supposition that it requires no backing. Assume the joint of rupture at the springing CD; draw a line from the division 36 parallel to C D, and it will cut the line AO in e; join e with 695, which gives a line to which the direction of the line of thrust, at its commencement, is perpendicular, on the supposition that the rupture is at CD, and therefore that the line of thrust is there perpendicular to CD. The line 69.5 and e will, however, be found to make a greater angle with the joint 1, 0, than 270, or. the limiting angle of friction, and a perpendicular to it from C would cut the intrados almost imme- diately. Therefore, under the load assumed, the arch cannot be maintained in equilibrium without backing. Through 69.5 draw a line, making exactly the limiting angle of resistance with the joint 1, 0; let this line cut A O in E. = 69.5= the amount of vertical force, in cubic feet Supposing the joint of rupture still at C D, and drawing a line parallel to this joint through e, the portion it will cut off the line A H will represent the amount of backing and arch-ring necessary to maintain equilibrium under the given circumstances. This amount * BRICK AND STONE BRIDGES. 215 = 115 feet, is much too large to be carried out in practice, and we may conclude that the joint of rupture is much higher up than when no load is applied. The variety of lines of thrust and dispositions of forces, consequent upon a change in the assumed amount of horizontal force, lead to a proper understanding of the phenomena in the subject we are considering, and are well deserving of study. The following extract from Professor Moseley's Mechanical Principles of Engineering, will here much assist the reader: .. Suppose the mass A B D C, Fig. 9, to be acted upon by any number of pressures, among which is the pressure Q, being the resultant of certain resistances supplied by different points in a surface BD, common to the mass and to an immovable obstacle B E. "Now it is clear that under these circumstances we may vary the pressure P, both as to its amount, direction, and point of application in A C, without disturbing the equilibrium, provided only the form and direction of the line of resistance continue to satisfy the conditions imposed by the equilibrium of the system; that is, that it nowhere cut the surface of the mass except at P, and within the space BD; and that the resultant pressure, upon no section, MN, of the mass, or the common surface, BD, of the mass and obstacle, be inclined to the per- pendicular to that surface at an angle greater than the limiting angle of resistance. "Thus varying the pressure P, we may destroy the equilibrium, either, first, by causing the resultant pressure to take a direction without the limits prescribed by the resistance of any section, MN, through which it passes, that is, without the cone of resistance at the point where it intersects that surface; or secondly, by causing the point Q to fall without the surface BD, in which case no resistance can be opposed to the resultant force acting in that point; or, thirdly, the point Q lying within the surface BD, we may destroy the equilibrium by causing the line of resistance to cut the surface of the mass some- where between that point and P. "Let us suppose the limits of the variation of P, within which the first two conditions are satisfied, to be known; and varying it, within those limits, let us consider what may be its last and greatest value, so as to satisfy the third condition. 216 "Let P act at a given point in A C, and in a given direction. It is evident that by diminishing it under these circumstances, the line of resistance will be made continually to assume more nearly that direction which it would have if P were entirely removed. Provided then that P were thus removed, the line of resistance would cut the surface,—that is, provided the force P be necessary to the equilibrium,-it follows that by diminishing it, we may vary the direction and curvature of the line of resistance, until we at length make it touch some point or other in the surface of the mass. "And this is the limit; for if the diminution be carried further, it will cut the surface, and the equilibrium will be destroyed. It appears. then, that under the circumstances supposed, when P, acting at a given point and in a given direction, is the least possible, the line of resistance touches the interior surface or intrados of the mass. << In the same manner it may be shown that when it is the greatest possible, the line of resistance touches the exterior surface or extrados of the mass. ઃઃ BRICK AND STONE BRIDGES. "The direction and point of application of P in A C have here been supposed to be given; but by varying this direction and point of application, the contact of the line of resistance with the intrados of the arch may be made to take place in an infinite variety of different points, and each such variation supplies a new value of P. Among these, therefore, it remains to seek the absolute maximum and minimum values of that pressure. "In respect of the direction of the pressure P, or its inclination to A C, it is at once apparent that the least value of that pressure is obtained, whatever be its point of application, when it is horizontal. (( There remain, then, two conditions to which P is to be subjected, and which involve its condition of a minimum. The first is, that its amount shall be such as will give to the line of resistance a point of contact with the intrados; the second, that its point of application in the key- stone A C shall be such as to give it the least value which it can receive, subject to the first condition." It has been observed above, in reference to Fig. 8, that the angle of rupture, under a heavy load such as we have been dealing with, would be much higher up, and in practice it will be found that we may C BRICK AND STONE BRIDGES. 217 assume that joint to be at a point where a line would form an angle of from 34° to 40° with the vertical. The amount of backing is then not only manageable, but also serviceable without being an overload in the shape of an unnecessary mass on the abutment. We shall find after going into the next, Fig. 10, that the total weight amounts in this case to 164 cubic feet of stone, or to 1858 lbs. per inch width of the arch; and this is distributed over the length of the arch joint. The line of thrust is, as already stated, the resultant of an indefinite. number of parallel forces pressing on the face of each joint; the pressure then communicated by one voussoir to the other is distributed along the whole surface of the joint in such a manner that the sum of the moments on one side of the resultant, or line of thrust, is equal to the sum of the moments on the other, taking the point of intersection of the line of thrust with the joint as the centre. It follows from this. that the pressure at points on the joint remote from this intersection is very small when the point of intersection approaches very nearly to either the internal or external boundary of the arch-ring; inasmuch as the greater part of the pressure is, on the shorter portion of the joint, cut off by the line of thrust. We shall, therefore, find that the bulk of the pressure at the joint of rupture is at the internal edge of the voussoirs; and that in order that this be not splintered off, the position the line of thrust will assume will not precisely coincide with that of the tangent at this point, but be a little removed up the joint, still, however, keeping parallel to the tangent. Assuming the ultimate strength of the stone at 1500 lbs. per square inch, which we may do with safety, and the value of the thrust at the joint of rupture being found equal to 1858 lbs. along the whole joint for each inch of arch width, we may allow something near one inch as the distance of the line of thrust from the intrados at this joint. This is the position the line of thrust naturally assumes, for as soon as the yielding of the material, arising from too large a pressure at the edge, takes place, the horizontal force slightly increases, until it throws the line of thrust sufficiently within the arch-ring to prevent ultimate injury; indeed, it may be laid down as a rule, that an arch never fails at the joint of rupture first, the line of thrust must cut the extrados somewhere below Q 218 BRICK AND STONE BRIDGES. this joint, or the arch will remain standing-the horizontal force generated by the tendency to fall inwards always increasing sufficiently to keep the line of thrust from cutting the intrados. And now, referring again to Fig. 10, drawn to a scale of 4 feet to 1 inch, and in which the scale line A H is again drawn to 20 feet to 1 inch, we shall take the angle of rupture at 34° with the vertical, which will be at the joint 4,4'. Any backing above the joint ab will be worse than useless, only adding to the horizontal force. We shall now only take the five first voussoirs, equal to 15 feet, to be added to 69.5 feet due to the load. Scale this off on the scale line AH, and we shall have the total vertical pressure acting in conjunction with the horizontal force of the opposite semi-arch upon the joint ab; the reaction on this joint must cut the vertical line passing through the centre of gravity of the mass 1 l'ab, at the same point where it is cut by the line of thrust on the joint 1 1'. Draw the line 15, E, parallel to a line, making a very small angle with the radius a O, and join the point 69.5 with E. A perpendicular to this last line, passing through C, will cut the vertical through the centre of gravity of the mass 1 1' a b, at a point G, through which a line may be drawn perpendicular to the line joining the points, 69.5 and E, which will be wholly within the arch-ring. The oblique pressure represented by the line joining the points 15 and E, is equal to the weight of 164.5, which at 136 lbs. to the cube foot, will be equal to a pressure of 1864 lbs. on an arch-ring of 1 inch in thickness. The line of thrust being found on the line a b, it will be below this joint that we must place the backing to control it and confine it within the arch-ring. A small addition of the triangular piece af 4, over the voussoir will make this latter equal to 3.6 feet; set this off on the scale line, and join the points 3.6 and E, which gives a line to which the line of thrust is perpendicular at its intersection with the joint 4, 4′. Produce the line Gd to cut the vertical which passes through the common centre of gravity of the mass a b 4' 4f, and through the point of intersection draw a perpendicular to the line E, 36, cutting BRICK AND STONE BRIDGES. 219 the joint 4, 4'. It will be observed that the line 36, E, makes a small angle with the joint 4, 4', inclining from it, whilst in the angle made by 15, E, with the joint a 6, the line inclined to the joint. From this we may infer that the line of thrust becomes tangential to the intrados somewhere between 6 and 4', and is leaving the intrados, and taking a direction towards the extrados, and requires backing. If we now add 4.4 to the area 6 of the two voussoirs 4 4' 5 5', we shall bring the line of backing to . Set off 4:46 104 upon the scale line, and join this point with E. As before, produce the line of thrust to cut through the line passing through the common centre of gravity of the mass ƒ4 4′ 5′ 5 h, and through the intersection draw a perpendicular to E, 104. In a similar manner for the backing over the remaining two pairs of voussoirs, we shall have to set out on the scale line 14 and 15 feet; and then proceeding, as we have already done, with regard to the lines passing through the two centres of gravity of the two pairs of arch- stones and superincumbent backing, the line of thrust, and the lines. joining 14 and 15 with E, we shall find that the line of thrust cuts the joint CD sufficiently within the arch-ring to secure stability. The value, in cube feet of stone, of the oblique pressures on the arch, we can obtain by measuring with the scale the oblique lines joining E with the figures on the scale line. Thus, the oblique pressure on the springer will be found equal to 190 cube feet, or 2154 lbs. for every inch in width; and taking, as already observed, 1500 lbs. pressure on the inch, nearly two inches from the extrados at the springing must be the minimum for the extreme limit of the line of thrust at the springing. It will be remembered that we have taken 75 tons as the load on the crown of the arch, a very extreme case, and one which compels the line of thrust to assume the direction shown on the diagram, and to come very near the extrados at the springing. In almost all cases it will be much further inside the ring, for it must be remembered that the only necessary points of contact, or nearly so, are at the extrados at the crown, and at intrados at the joint of rupture. With regard to the thickness at the crown, let it be observed, that Q 2 220 BRICK AND STONE BRIDGES. at this point the line of resistance approaches very near to the extrados; consequently the effectual pressure on the lower portion of the arch- stones is here very inconsiderable. It is here that the arch-ring may be diminished in depth, and proportionately increased towards the haunches and springing, where this addition more than takes the place of so much backing. This is now becoming a very general practice. By altering the load on the crown, and, consequently, the load on the scale line as well as the other dimensions, the reader will have an opportunity of studying the lines of thrust, and, at the same time, of obtaining the value of the oblique pressures by measuring with the scale the oblique lines joining E to the several dimensions set off on the scale line. The following is given in Ware's old Treatise on Bridges as a method of finding the extrados of an arch of equilibration, which, however, we only introduce as regards the subject of thickness of abutment. (c Having the span, intrados, and depth of arch at the crown, to find the extrados, divide A C, Fig. 11, into any number of parts, as at 1, 2, 3, 4, 5, 6, 7, 8, &c., and through these divisions draw, O, a, O 2 b, 0 3 C, O 4 d, 0 5 e, O 6 ƒ, 0 7 g, &c. ; also through 1, 2, 3, 4, 5, 6, 7, &c., draw the verticals, 1 p, 2 p, 3 p, 4 p, 5 p, 6 p, &c., and make each of these verticals equal to CD; through p, p, p, draw the horizontals p a, p b, pc, pd, pe, pf, &c., to cut 01 a, 02b, 0 3 c, 0 4 d, &c.; and the points of intersection a, b, c, d, e, f, &c., will be the points through which the curve of intrados will pass; this first description refers to that side of Fig. 11, where the extrados is dotted. “To find the thickness of abutment-produce pa, pb, pc, pd, pu, pt, &c., and make a y equal to p a, b x equal to p b, c w equal to p c, d v equal top d, and e u equal top e, &c.; from t, u, v, w, x, y, let fall verticals; from ƒ, perpendicular to 6fdraw fo; through e, perpendicular to 5 e draw eo; through d, perpendicular to 4 d, draw do; through c, perpendicular to 3 c, draw co; through 0, 0, 0, 0, &c., which are the points of inter- section of the last lines drawn, and the last verticals let fall, draw the curve 0, 0, 0, 0, &c., which will be the line of thrust; join OR, and bisect it at G, and from G at a centre, with radius G O, describe the curve R; join 6 R by a straight line 7 R, which will give the limits of / BRICK AND STONE BRIDGES. 221 abutment; this method borders remarkably near practice; if from 6 we let fall a vertical 6 T, ST will be the thickness of abutment, and V may be considered the point of limit for the counterfort, and the curve 0,0,0,0 V, the line to which the courses of masonry in the abutment should be perpendicular. Fig. 12 shows an elliptic arch extradosed, with the thickness of abutment found in the same manner. "" The reader will not fail to see of what an excessive mass the abut- ment and counterfort are composed; still a large number of bridges have been, and may still be built with such proportions. In Fig. 13 is another system, deduced from the same principles which we have been already examining at some length, considering the amount of space we have in these pages. The scale for the outline of the arch is 10 feet to the inch, and for the triangle of forces 80 feet to 1 inch. The joint of rupture, with the arch loaded to the extent already assumed equal to 69 6 square feet, will be at the joint 4. This quantity is marked on the scale line. From this point to 2 O, the distance repre- sents the amount due to 3 pairs of voussoirs, equal to 18, plus 2, due to the small amount of backing over them. A line drawn through this point, parallel to joint 4, cuts the vertical through H, at E, and defines the amount of horizontal force generated by the length HE, which, by scale, is equal to 205 square feet. The line of thrust is carried down through the lower voussoirs by the same method we have before pointed out. The backing is taken as high up as practicable, and measures, together with the arch-ring, 67 feet, without the portion over the abutment. Notwithstanding this great weight, the line of thrust, by reason of the large proportion of horizontal thrust, forces its way out of the boundaries of the arch-ring beyond the joint 6. The extreme load we have assumed makes this the more forcible, and will make the more intelligible and forcible the two following conditions :-up to this angle build up solid, and increase the depth of the arch regularly from the point a up to the abutment. A practical illustration is given of this at Figs. 14 and 15, in which will also be seen the value of the counterforts; not from their additional weight, but from their extension of base, and increase of width gained to the abutment. Returning to Fig. 13, the line 204 represents the oblique force on its egress from 222 BRICK AND STONE BRIDGES. the arch-ring. Under the extreme supposed load, it will be observed that, notwithstanding the amount of backing, as well as of the mass CD = 60 square feet above the abutment, so great is the oblique force generated =245 square feet, that the whole has but little influence in controlling the direction of the line of thrust. To the level of the springing the abutment measures 20 × 8 feet. This divided by 4 gives 40 square feet for each division in height. These quantities are marked off on the scale line as representing their weights in feet of stone. Observe that these masses of 40 feet have their centres of gravity in one common line, which intersects the line of thrust at G. Draw the lines a b, c d, ef, g h, dividing the heights of the abutment into four equal parts perpendicular to 40′ E, 40″ E, &c., draw the lines from G; the intersections with a b, c d, &c., will give the direction of the line of thrust. : It will now easily be seen why in so many bridges the courses of masonry are built radial to the centre from which the arch is struck. It will also be seen in the two parallels at Figs. 14 and 15, which is after the system long pursued in Mr. Brunel's works, that the force opposed to the line of thrust is the power of resistance to crushing in the materials in the small "jack-arches." It will be seen what a great amount of saving in material is effected, notwithstanding the great spread at the base of the abutment, which is of course one of the most desirable objects to attain. Inasmuch, however, as many will still adhere to the old form of abutment, another parallel is added at Fig. 16, where the mass of brickwork or masonry is reduced by jack-arches in the face of the abutment. We cannot keep it too strongly impressed on our minds, that one of the greatest safeguards, equal almost to the soundness of the work itself, consists in the plentiful earth backing and punning up in good sound loamy stuff, or clay carried up to the full height of the abutment, with a thickness of from 6 to 10 feet, and punned in layers of about 6 or 9 inches. This work requires careful overlooking. The last three diagrams are drawn to a scale of 10 feet to 1 inch, and in getting out a section for an arch and abutment, for spans from 20 to 40 feet, there is little more to do than to copy. For greater spans, proportion will give the required dimensions. TECHNICAL TERMS. 223 In very flat arches the backing may be carried up the level of the soffit of the arch, particularly if the arch be under a railway; and the arch should always be unequally extradosed, as in Figs. 15 and 16. For arches of greater rise, say one-third of the span, it will be sufficient if the backing be carried up to a level of within 2 or 3 feet of the soffit, according as the arch may be under or over the rails. On the subject of piers very few observations will be sufficient; their thickness in practice is regulated by the span, and from one-sixth to one-seventh of this is generally taken for the width of the pier. A less thickness would be sufficient, but rather than diminish this width it is better to economise material by having jack-arches in the pier, by which a considerable saving may be effected. When piers are of a greater height than about 20 feet, a slight batter should be given to the face of the pier; from of an inch to 1 inch per foot, as the height of the pier becomes very great, will be sufficient. Where this height does not exceed some 20 or 25 feet, and the pier is brickwork, one or two sets-off a few feet above the base will answer the purpose. The footings should always be sufficient to give a considerably increased width of base. We have as yet been speaking of arches of a span equal only to 30 feet. For larger spans we should have a greater number of points of division, but there would still be the same proportions. Having gone through, or rather touched so far upon the subject of the arch, abutments, piers, and counterforts, it becomes desirable to say a few words as to the materials of which they are composed. The word Ashlar applies to masonry of large scantling, and the material and workmanship should be of the best; it may be 12 inches thick, or more, 4 feet by 2 feet on the bed, or more, and laid alternately in headers and stretchers; joints should overlap 12 or 15 inches; the joints and beds should all be dressed fair and true, if not chiselled, which they should be for all exterior work. The face work must be fair tooled, or the joints may be chamfered, or a margin-draft run round about 1 or 2 inches wide, and the interior may be left quarry- faced. Very often Ashlar requires to be dowelled, that is, the blocks connected by hard stone dovetailed dowels. Whatever stone may be used, the dressing is a most important 224 TECHNICAL TERMS. feature, and generally, the larger the blocks the greater the care required in this particular, as to levelling the beds, or dressing them to the proper angle, or in the squaring. If the beds are irregular, or in winding the bearing is unequal, and the stone tends to split and rend at bearing points, which act as fulcrums, and in fact may have to be loaded with an enormous weight. This cannot occur if the beds. have been well levelled, as the bearing is then equal throughout the bed. The rent receives rain-water, and allows it to lodge, and the structure becomes exposed, often in a dangerous manner, to the effects of frost. If the blocks of stone are fairly and truly dressed, the trouble of laying them will be comparatively slight; care must be taken that, in order to hide or disguise a thick, clumsy joint, the blocks be not pitched forward on their edges, as they will then be sure to splinter at the edges, from the weight bearing on the angle. To disguise the careless dressing of blocks, and to level them when laid, workmen are very apt to underpin large blocks of stone with wedges of wood or splinters of stone, thereby laying the foundation of rents and fissures when the work settles. The setting bed of each course should be brought true and level to receive the next course, which must rest solidly and truly upon it. The face of every stone in a wall may be left quarry-faced, or as it comes from the quarry, but each stone should be wrought with a setting margin. The dressing of the beds of large blocks of stone may easily be tested by laying the edge of a straight rod or rule (otherwise a straight edge), along the surface of a block from angle to angle, and from side to side, when any winding or irregularities in the setting beds will easily be seen, by parts of the edge of the rule lying close to the stone, whilst cavities admit the light between the bed and the rule. In building with ashlar, or other large stone, care must be taken that pebble and small stones be not used in the mortar, as these will act as so many wedges on the beds; but in grouting, or filling in at the back of masonry, there is no objection to splinters being used; and in filling in angles and odd corners in rubble backing, they may come in advantageously, not only to save waste of mortar, but because, when the mortar sets, the work will be better filled; unfortunately, TECHNICAL TERMS. 225 unless under the eye of a careful inspector, this is where masons will often not take the trouble to use splinters of stone. Block in course consists of masonry in which the stones are also of a large size, but less than ashlar masonry; for instance, the blocks may be some 7 inches thick, and 12 or 18 on the bed; or 15 by 24 on the bed, and 9 inches thick; the beds and joints carefully hammer- dressed, fair, true, and square; whether through stones or not, one- fourth the length of each course should be from 2 to 3 feet long, according to the size of the block in course, or the thickness of the wall. These should be laid nearly equi-distant, and so as to bond into the backing, if any. Rubble is a coarser kind of masonry, where the stones should be well bonded together; no stone should contain less than a cubic foot, except for pinning, the stones should be flat-bedded, and plenty of mortar and grouting used to make all solid. In districts where stone is abundant, heavy walls in rubble are run up very cheap. Another material is brickwork, of which such incredible quantities have been consumed in railways. Amongst the evils of omission or commission which we have to guard against in brickwork, the following may be enumerated:-. The beds of mortar being very unequal in thickness, and exceeding of an inch. The introduction of brickbats, or pieces of brick, except as closers, whereby the perpendicular joints in two courses may lie one above the other, which should not be. The absence of mortar in the joints, particularly in the interior part of the work, either on the bed, the side, or the head of a brick, and neglecting to grout with fine mortar at least at every fourth course, when required. Running up side joints without any bond; bricklayers are apt to do this where beds are horizontal by the side of battering beds. Running up too great a height and too little width of work at a time, thereby injuring the connexion of the courses by unequal settlement. The neglect in dry, hot weather of wetting the bricks before they are laid on the mortar, when, if a brick thus laid be lifted up again, it will be found that the mortar does not in the least adhere to it. 226 TECHNICAL TERMS. Each brick, as it is laid, should be pressed, or rather rubbed, into the mortar. The levelling of the courses should be carefully attended to. In arches, where the bricks, or some of them, should be cut, this precaution is often totally neglected. Bricklayers will sometimes in such work, where it is concealed, make a mortar joint 1 inch thick. All these evils bricklayers will introduce unless their work be closely watched, and sometimes ripped up; and, although each evil by itself may appear of trifling moment, it is only by avoiding one and all that good brickwork, as rare in modern construction as it is sound and deservedly admired when met with, can be built. In the construction of brick arches, a great evil consists in the brick- layers, when reaching the centre or keying, attempting to fill up a void of 4 or 5 inches with one brick, and thick cement, and mortar joints, or brickbats. Such a proceeding should be stopped, and 4 or 5 bricks being removed at each side, their places should be filled up with the largest-sized bricks, picked out for the purpose, so as to fill the space at the keying in a proper manner. In engineering work, brickwork is only employed in the construc- tion of an arch from motives of economy, not only where stone is not easily attainable, but also to avoid the expense of cutting the arch- stones to their true form. In this sense, also, bricks have the advantage of being more easily raised in moderate quantities, and, from their small size, of being more easily handled and placed. The bond in good brick- work gives a far better connexion than that obtained from inferior masonry. Compared, however, with stone, brick is a frangible and porous material; at least that description of brick too often resorted to from motives of false economy, and rain and frost often perform quick justice on these defects by fracturing and splintering the materials in the intrados, which consequently drop out, thus commencing the destruc- tion of an arch, unless careful precautions be taken to prevent the access of surface water to the extrados, by covering the arch with an impervious material, such as good puddle or asphalte properly prepared and laid on. Bricks, being in rectangular forms, would necessitate guaging to proportion their outer surface. to the outer periphery of the ring, and this economy puts out of the question. Moreover, this precaution in MASONS' TOols. 227 a large arch, comparatively speaking with regard to the size of bricks, would be useless, in consequence of the small depth of a brick-ring. The auxiliaries, therefore, to obtain the curve of the arch are a series of wedges of mortar or cement. The latter, though more expensive, is often used in the upper portion of an arch. A brick arch may be considerably strengthened by the introduction of hoop-iron between the courses, more particularly at those parts of the intrados and extrados where there would be a disposition to open at the joints; also by facing with stone quoins, which should be of a good These length and a good bond into the brickwork. See Fig. 17. quoins should have their soffits fair tooled, and they should underlay the bricks by a couple of inches, with their edges champered off, when they will act as dripstones. Much of the above observations will hold with regard to the stone voussoirs of an arch, but in a less degree, inasmuch as the arch-stones are cut to a radiating form, and the intervening mortar is no longer of wedge shape. The thickness of the mortar should only be sufficient to act as a cement, and entirely fill up vacuities between arch-stones. The greater the span, and still more the less the rise of the arch, the greater the necessity of strict adherence to this important point will be. With regard to the filling in of backing or spandrils of railway arches, which are generally of only small or moderate span, the work should be as sound as any other part, but appearance is not here requisite. Rougher materials may be used, but they should be hard, dry, and tolerably well-shaped. Sufficient mortar or cement should be used, and in these concealed parts of a construction bricklayers and masons will introduce as little as possible if they are not watched. In masonry there should be sufficient binders or bond stones, and all the work should be well and closely packed and tied together. It must not be forgotten that, although this work is out of sight, it has to perform the duty of resisting the thrust of the upper portion of the arch tending to overset the lower. MASONS' TOOLS. These consist of a level, straight-edges, a plumb rule, a square, and 228 CENTRES FOR RAILWAY ARCHES. a bevel; also, as cutting tools, of the point, which cuts narrow furrows along the surface and leaves narrow edges between; the inch tool, which cuts away the ridges; and the boaster, which leaves the surface nearly smooth. There is also the broad tool, performing two kinds of opera- tions. Suppose the first impression made by the whole breadth of the tool, which may be 2 or 3 inches, be called a cavity, one operation is to make the cavities follow one another in a straight line until the length or breadth of the stone is gone over; then follow successive equidistant lines of this, until the whole surface has been gone over. This is called stroking, and gives a kind of fluted surface. In the other operation every successive cavity is repeated in new equidistant lines. throughout the length or breadth of the stone; a new series of this follows, and again another, until the whole surface is brought down. This is called tooling. A stone is taken out of winding by the point, and then with the inch tool. When stones are very unshapely, a jedding axe or scabbling hammer is used to bring it into shape. One end of the jedding axe is flat to strike off protuberances, and the other end is pointed to bring down the different surfaces nearly to the intended planes. The point is sometimes called a punch, and boasting is sometimes called droving. The broad tool is sometimes used as broaching without previous boasting, but the work is never so regular. Where the stone is very hard, the scabbling hammer is used for a great deal of the work; by this tool the surface is worked until reduced nearly to the intended plane. This manner of dressing is sometimes called nidging. The term rubbed work is applied where the surface is brought down by means of sand. To describe an elliptic arch from three centres, the span and rise, or the major and semi-minor axes being given:-In Fig. 18, let A B be the span, and OC the rise; complete the parallelogram COBD, by making BD parallel to OC, and CD parallel to OB; bisect BD at E, and join EC; make O F equal to OC, and join DF, cutting CE at G ; bisect CG at K, and draw KL perpendicular to CG, cutting Co produced at L; from L as a centre, with radius LG, describe the curve MGC; through MB draw M Bn; join n L, cutting A B at N, and CENTRES FOR RAILWAY ARCHES. 229 transfer BN to AN; N, L, N', will be the three centres required for describing the curve. Having the span and the rise, to describe a semi-ellipsis with five centres-In Fig. 19, let AB be the span, and OC the rise; from centre O, with radius O A, or O B, describe the semicircle AD B, and divide it into six equal parts at 1, 2 D, 3, 4, B, with radius OC; and also from centre O describe the semicircle ECF, and divide this also into six equal parts, as at a, b, C, c, dE; through 1, 2, 3, 4, draw parallels to CO, and through a, b, c, d, draw parallels to AB; join the points of intersection f, g, h, i, which will be points on the elliptic curve; bisect A ƒ, fg, g C, C h, hi, i B, as at k, l, m, n, o, p; through m and n draw m G, and n G, perpendicular to C and g C, intersecting CO produced at G, when G will be a centre; through 7 and o draw /H, o H, perpendicular to fg and hi, and intersecting m G and n G, at H and H'; and H and H' will be two centres also; through k and p, perpendicular to Af and i B, draw k K, p K', intersecting A B at K and K', which will be the two last centres required for the curve of the arch. The greater the number of divisions in the semicircles the more numerous the centres, and the nearer will the curve described approach the elliptic. TO SET OUT AN ELLIPSE. A much better way of setting out an ellipse is in the following manner, in which the semi-major axis and the semi-minor axis are marked off on a slip of paper, which is so worked round that by pricking off at the end of the semi-major axis the curve is most correctly obtained. Ex. Let AB, fig. 20, and CB be the semi-major and semi-minor axis of a quarter of an ellipse, or half the headway of an arch. Take a slip of paper and lay it along AC, the semi-major axis produced, so that the edge of the slip coincides with this line, and prick off on the edge the points A and C, and let C be called D. Next lay the same edge to coincide with BC, produced, and let the point marked A on the edge of paper coincide with B, and mark off the point C on the same edge, and call this point C. Now move the edge of paper round, so that the point called C shall be on the semi-major axis, as at C, C, C, &c., and the point called 230 CENTRES FOR RAILWAY ARCHES. 1 D, on the semi-minor axis, at D, D, D, &c., until A, on the slip of paper, is again at A on the major semi-axis, and D on C, coinciding with A C. and The dotted lines represent the slip of paper as it is worked round, and by pricking off at the end A, any number of points on the curve, marked by dots on the diagram, will be obtained. This very simple method is well known amongst practical men generally, but there are so many persons unacquainted with it, and so many works treating on practical geometry in which it is omitted, that perhaps no other apology need be offered for giving it here. FIG. 20. Having the rise and span of a segmental arch, to find the radius. In the annexed figure, A B is the span, and CD is the rise. Call the span S, and the rise V; required the radius, R. Then, 9° S or 900 4 V, or D 1 I 1 1 V R = 1/2 (1 S2 1 + 4V Or in figures, let CD, or V, the rise be 9 feet; and let AB, or S the span be 30 feet; then and and = 916 الا = 4.50; 2 30² = 900; = B 81 × 4 = 324, 324 = 2.7777 + 1 = 3.7777; V or 4.50 x 3.7777 16.999651, or radius required. 2 CENTRES FOR RAILWAY ARCHES. 231 or Or the rectangle under the segments of one chord being equal to the rectangle under the segments of another, we may make use of the following rule:- or by figures and and and and 225 9 Jong 2212 2 34 2 8c - C 3 ÷ V+V 2 (30)² = 225 = 25; and 25 + 9 = 34; = = With regard to the width of the arch-stones at the intrados, we may take from to of the depth at the crown, remembering that the number of voussoirs must be an odd number, as one of them will be the key-stone, and their number multiplied by their width should be equal to the length of the arc, allowance being afterwards made for mortar; the dimensions should be figured on the drawing, for the intrados and extrados, and the Engineer should see that the arch-stones. are worked to those dimensions, within the limits of practical means. To rectify the arc of a circle, or to find the length of a circular line, either of the following rules are sufficiently near for practice:- Let C be equal to the chord of the arc, or the span, A B, 30 feet, Fig. 21, and let c be equal to the chord of half the arc A C, 9 feet and a the length of the curve required; then X R 17 = Radius. 8c-C 3 √ AD² + DC = 17.4928557; 8c 17.4928557 x 8 = 139.9428557; = 8c C139.9428557-30 109.9428557; = 109.9428, &c. 3 x = 36·6709 = length of arc. = 36.6709, &c. ; 232 CENTRES FOR RAILWAY ARCHES. Or as before, putting C for A B, span of 30 feet; and c for CD, versed sine, or rise of 9 feet; and a for length of curve required, we have or in figures, and and and M 16 x = C + 3 rise, or c² c² 81 x C or 30 2430; 3 C² + 2 c² or 2700 + 162 = 2862; 194402862 = 6·7924 ; C = 30 + 67924 = 36.7924 length of arc. And having found this length, if we divide by about one-half the depth of arch-stone, say 2 feet on the face, we shall obtain the number of voussoirs or arch-stones, and also have their dimensions at the intrados, allowance to be made afterwards for mortar; here reducing 36.79 to inches, we get 441 inches, and 441 divided by 11.31 inches 39, almost exactly, and nearer than we can can ever obtain it in practice; of an inch is the least quantity masons can be expected to observe; we shall therefore have 39 voussoirs of 11.31 inches thickness at the intrados, and if we allow inch for the mortar joint, we shall have 10.91. For the thickness at the extrados, see page 117. We have now the span, the rise, the radius, the depth of the arch, the division of the arch into arch-stones, the thickness of the piers, and the width of the abutment at the base, though circumstances will continually modify this dimension between and of the span; under 20 feet it will be nearer . 8 c² C C² + 2 c² 81; = = The practice of Engineers varies very much with regard to the backing, or filling in of the spandrils; our railway bridges are often equally extradosed, that is, the extrados is parallel to the intrados, though certainly not because it is the strongest form of extrados ; sometimes the arch-stones increase towards the springing, and the extrados is often then a curve of contrary flexure from about an angle of 45°; sometimes also the depth of voussoirs increases by a similar curve to that of the intrados, becoming at the springing of twice the CENTRES FOR RAILWAY ARCHES. 233 thickness of the crown. The spandrils may be filled by solid masonry, surmounted by spandril arches, or by solid masonry and spandril walls, or by solid masonry alone; the object' is to receive the thrust of the upper portion of the arch and of the load superimposed, and to dissipate vibration, and where spandril arches and spandril walls are used, relieve the upper portion of the arch from vertical pressure; in arches up to 50 feet span, the spandrils may be filled in with solid masonry. We may proportion the depths of the springers when used in the following manner :-from 20 to 30 feet span, 1 foot for the depth of springer; from 30 to 35 feet span, 1 foot 3 inches; from 35 to 40 feet, 1 foot 6 inches; 40 to 50 feet, 2 feet; 50 to 60 feet, 2 feet 6 inches and 3 feet; less dimensions may be allowed for string courses; a good depth of string course acts like a chain over the spandril walls; make all mouldings plain, bold, and so weathered and throated that water cannot lodge. Stone if at all costly may be dispensed with in most ordinary cases. A transverse section through an arch should show dimensions between the faces of the arch, the thickness of spandril walls, the dimensions of string courses, parapets and coping; and these dimen- sions should all be figured. Where any of these parts are decorated by mouldings, enlarged or detailed drawings should be given, showing the centres of curves and the bevels; sections of wing walls should also be given; and where brick is the building material, care must be taken to count the dimensions by bricks, half, and quarter bricks, or these dimensions have no real value beyond the drawing. The young practi- tioner must never lose sight of one important point on the subject of working drawings, that they are only preparatory to the construction of a building, and that this important point, from ignorance or careless- ness, is so often neglected, that, one or two dimensions having been taken, the drawing becomes worthless; hence, a common observation amongst workmen-"Who ever saw a working drawing that could be worked from ?" An Engineer in charge of works should consider himself responsible for the value of working drawings, making, how- ever, some allowance for unexpected circumstances; whether the material be stone or brick, iron or wood, a little thought, observation, R 234 CENTRES FOR RAILWAY ARCHES. and study of material will guide him in giving instructions for working drawings which may be worked from; and in setting out the dimen- sions on paper, he should consider himself as setting out the work itself. As regards the principal lengths, widths, and heights, a cross section to a large natural scale taken on the site determined on, will generally save him from blundering, as regards section, elevation, and plan; the neglect of this precaution will ensure two things, viz., a wide difference between the work constructed and the drawing, and the impossibility, without making a fresh drawing, of setting off the quantities of work performed. It must not be supposed that an affecta- tion of fastidious care is here pretended, involving useless trouble to others and loss of time, and it must, on the contrary, be considered that we are alluding strictly to practice generally, and that experience alone suggests these observations. Generally, the cases of bridge-building which we have to deal with are bridges over a cutting, or under an embankment, or partly of both, as where a road has to be raised; or it may be over a railway, where the road has to be raised so as to give sufficient headway for the locomotive. Parallels for all these will be found in Dempsey's Brick Bridges, taken from working drawings, making allowance for improvements. These are not recommended as copies, but to be treated more or less according to the principles above given, in order to improve upon former constructions. For a double line of way, the clear width between the parapets, piers, or abutments, may be 26 or 27 feet (Fig. 22), though often made 28 and even 30 feet. If to this we add the thickness of the two parapet walls, where used, we shall have the entire width of the arch. See Fig. 22. For roads, we must be guided by legal enactments made to regulate the construction of railways; a short abstract of these, as regards roads and bridges, will be given at the end of the chapter. In crossing canals, we are generally tied down by special agreements. We will not extend beyond a few words our remarks on the centres of railway arches; they must be viewed as the means by which the materials forming an arch are to be supported until the arch is keyed in, and also as the moulds by which the intended curve is given to the | CENTRES FOR RAILWAY ARCHES. 235 series of stones, bricks, &c. Designs for centres are not expected from the Engineer, it being the business of the Contractor to provide these, but it is distinctly the business of the Engineer to see that the centres employed be of correct form and dimensions, of sufficient strength for their intended purpose, and so framed as to be practically unyielding under the load they are to bear; it is, therefore, necessary that he should take this subject into general consideration in the superin- tendence of railway works, more particularly under certain important points presently to be pointed out, without the slightest pretension, however, to allude to bridges of vast span, or to those of very small rise, where the centres become of the last importance even in minute details of composition and construction. As soon as the voussoirs of the arch assume an inclination to the horizon, whereby the weight of the stone overcomes the friction between the connecting surfaces, the arch-stones then begin to bear upon the centres, which latter must be capable of bearing this increasing weight, and of keeping the stone upon its inclined bed; when a soft bed of mortar is interposed between two arch-stones, this inclination to the horizon may be considered an angle of about 30 degrees,* after which every stone bears the more heavily on the centre, until the power of the weight becomes sufficient to force inwardly the sides or haunches of the centring rib, and to force the crown upwards, unless the construction be such as to resist this pressure; and the flatter the arch, either in a segmental or elliptical curve, the more effective this pressure will be, and the greater, therefore; the requirements from the centres. When a vertical drawn through a centre of gravity falls without the lower voussoir, the whole stone may be considered as weight on the centre; even in small spans of 30 and 40 feet this.subject requires strict attention, as there can be no doubt that deficiency of strength in this direction, not from want of material, but ill disposition and bad workmanship, has occasioned many accidents to arches, as well also as the haunches of arches being loaded prematurely. When a centre rib is thus upreared at the crown, a heavy load must be there applied to weight it back, but it is very doubtful, in thus weighting the centre, whether we force it back into its original * Tredgold says 34 degrees. R 2 236 CENTRES FOR RAILWAY ARCHES. form; indeed this cannot be expected, and only an approximation to the first curve can be hoped for; a very little thought will make this apparent, and therefore, also, the necessity of attention to this subject. The greater the number of joints in the rib, the greater the liability to flexion, these joints being the points at which the parts of the rib pivot, and these, therefore, require support by framing, auxiliary tim- bers, strapping, &c. The above must be considered the first requisite in a centre; next follow an economical erection, and an easy removal, and economy will be best observed by employing mostly timbers of the common scantlings, and in such manner that the timber may be employed for general purposes afterwards. In designing or inspecting centres, it is more particularly at the angle where the whole weight of the arch- stones leaves, practically speaking, the lower voussoirs of the arch to rest entirely on the centre, that we must look for resistance to this weight, therefore, material should be disposed accordingly, and an angle of 50 or 55 degrees may be considered to be about this point generally, at least where the width of a voussoir is equal to about half the depth; centre ribs may be set at from 4 to 6 feet apart, these being extreme limits, and care must be given to secure them from any lateral motion; on the centres come what is termed the lagging, which are narrow planks set across from rib to rib. The supports of centres that are raised high above the ground, as in lofty viaducts, require particular attention, as the great length of leverage renders them particularly liable to serious lateral motion from vibration or other- wise; in all cases the timbers bearing the several ribs should be well braced together in the direction of the transverse section of the arch; it is a common custom to rest these supports on corbels projecting from the piers; but this must be considered more economical than beneficial. The easing and striking of centres requires care and watchfulness, and accordingly as the setting of the centre affords the ready means of doing this, so will be the facilities for obtaining a regular and steady settlement of the arch; since the voussoirs rest upon the centring, they will descend as the centring recedes from them, suddenly if the centre is suddenly removed, unequally at each side of the arch if the descent of the supporting centre be unequal, and this by fracture in some of the mortar joints, if this cementing matter be dry, or by an CAST AND WROUGHT-IRON GIRDERS. 237 unequal forcing out of the mortar, if too soft; either of these degrees of induration being, therefore, least fit for the easing of the centres. The means usually adopted for easing the centres of railway arches consists of double wedges, which being driven back equally at each end by men striking with mauls, allows the centre to descend as the wedges retire, and the quantity of release, therefore, may be easily ascertained as the operation proceeds; the men performing this task generally know perfectly well what they are about, but it is as well to observe that the great weight superimposed on these wedges during the construction of the arch forces the fibres of the wood together, occasioning at first great friction, which must not be overcome too suddenly and violently, as the result would be a shock; when the settlement of the arch is complete, the centre may be entirely removed. PART II. CAST AND WROUGHT-IRON GIRDERS. As regards iron bridges, it is only proposed in these pages to go into the subject of cast-iron girders and plate girders; by means of these we can span a space of 150 or even 200 feet. Iron structures of a more complicated character demand a volume to be of any service to the prac- tical man, instead of a few pages of superficial description which can only amuse a casual reader. Before, however, we proceed with these subjects, it will be as well to say a few words as to the subject of transverse strength, according to the present received opinions. Let A B, Fig 24, be any beam resting on two supports, A and B ;* let the beam be loaded in the centre; then A and B each carry one-half of the load, plus one-half the weight of the beam. Call the whole of the weight W. The strain on the beam is communicated by means of a · Mr. E. Clarke. 238 CAST AND WROUGHT-IRON GIRDERS. bent lever, of which the longer arm is half the length between the sup- ports, and the shorter arm is the depth of the beam. The reaction at A or B is the half of W, therefore as C D, the depth of the beam, is to A B, 2 beam. From this it follows, as a consequence, that the greater the span the greater the strain on the centre of the beam; hence the strength is inversely as the length of the beam. Also, every particle in the sectional area of the beam bears its pro- portion of strain, which we will calls; hence, the strength of the beam is directly as the sectional area multiplied by the depth-multiplied by s. But in a beam under transverse strain, the top is under a com- pressive force, and at the bottom this force is tensile; then the strength at top or bottom will be directly as the sectional area multiplied by the depth multiplied by s; the value of s depending upon the power of the material to resist compression or tension. Then, d x ax s = S. then, or, so is Let / be the length of the beam, between the bearings, in inches. d, the depth of the beam, in inches. a, the sectional area, in inches. W, the breaking weight, in the centre, in tons. S, the whole strain in tons, at the centre. s, the strain, per square inch, of sectional area, in tons. Now is the portion, in the bent lever, of resistance to the break- ing weight W, And And W to the pressure on the centre of the 2 d: S; that is, as the depth is to half the length, so is half the breaking weight W to the whole strain S. Put 10 = d; 100 = 7; 100 = W ; 100 2 Z 10: 10 50 : : :: : - W 2 S CL 100 : 250; 2 50 : 250. S CAST AND WROUGHT-IRON GIRDERS. 239 that is, the whole strain divided by the sectional area is equal to the strain per square inch. S, or s, will be compressive or tensile, accordingly as they are applied to the top or the bottom. Thus, in the above, if there be 25 square inches in the sectional area of the bottom flange, then But 250 25 and if there be 5 square inches at top, then 250 5 and then and And and "" = 10 the tensile strain per square inch; ******** = ;; =25= the compressive strain per square inch. #E Sx d or s xa x d = moment of forces, × 1 201 X W 2 × moment of forces, W Q; 4 × 8 × a × d = l × W. s x a x d that is, that 4 times the strength per square inch multiplied by the sectional area, multiplied by the depth, and divided by the length, is equal to the breaking weight. For s× 4, put C for the constant, and we get the following formula, 4 x s x a x d τ axdxc a x d x C 1 α = W ; W; W × Z X d × a Tons. In calculating for the bottom flange of a plate girder, C = 75 for a straight top 59.6 <= 25'0 for the bottom flange of cast-iron girder, رز "" در "" 240 CAST AND WROUGHT-IRON GIRDERS. Many of the above will be found useful in the first sketches of a design, since the length is always given, and the weight is assumed. The depth, if not compulsory, is some proportion of the length, and the strain, per square inch, for compression or tension, is regulated by the nature of the material, and the conditions of being in wrought or cast- iron girders. In practice we may consider that a load, uniformly distributed over a beam, is equal to half that load applied in the centre. In applying the formulæ in practice, reduce the feet into inches, and take the weights as tons. We must also remember that such an element as depth cannot be overrated, but width must not be neglected on account of lateral strain. Although, in all cast-iron works, a mixture of different kinds of iron in different proportions, and the use of hot and cold-blast are of great importance in girders, pillars, cylinders, &c., it is well known that whatever mixtures may be ordered, we have no guarantee that instruc- tions will be attended to. Test is therefore the only security remaining; this should, without any exception, be freely applied under an experienced person, but never to such an extent as to injure a casting. It is therefore that the testing load should never be more than one- third the breaking load; this will find out the defects, if properly applied, and more would injure the casting, even if sound. It is also important to remember that whatever means are employed to test a girder, it is not sufficient that the pressure just touch and then be withdrawn; a short time should be allowed to give the pressure time to come into full operation, and a slight vibration should be given whilst the beam is loaded. There are circumstances in which it is advisable not to make the breaking weight less than six times the load that can be brought to bear upon the girder, but it is rather exceptional than otherwise. A well-selected mixture of irons always produces strength, and no single kind of iron is ever employed, or but very rarely; but the selec- tion will depend on the part of the country from whence the casting will come, and sometimes motives of economy will be more potent still. A heavy casting and a light casting require different kinds of iron, and there are two kinds of heavy castings; the one may be in a close CAST AND WROUGHT-IRON GIRDERS. 241 solid mass, when a hard iron should be selected, as it will soften in cooling in a thick mass; but a long, and proportionately thin casting, such as a large girder, or a large water-pipe, requires a much more fluid iron, that it may run freely, and that it may not chill or become too hard in casting. It is desirable, in designing cast-iron girders, to bear in mind the following circumstances: that it is difficult to cast very large castings from uncertainty of contraction in cooling, and of the regular running of the metal; such, for instance, as girders of 30 and 40 feet in one length; that they are awkward to handle, and liable to damage in transit and erection; that any considerable increase in thickness of the casting increases the risk from air-holes from the coarse crystalline texture which large masses of cast-iron assume in cooling; that if in a casting there are any considerable differences of thickness, danger arises from corresponding differences or inequalities of contraction in the parts which are of different thickness. In Mr. Hodgkinson's work there is a table of fourteen experiments made on model girders, in which the distance between the bearings being alike, as also the depths, the proportions of the areas of the top and bottom flanges vary from equality to 1 to 6, and the strength of section per square inch is nearly 7 to 12, the total areas of section being 2.82 and 6.4. a x d × С. W = is the formula from which the constant of trans- ι verse strength is deducted, as already shown, so that for every different form of section the value of the constant C should be different. In this, as throughout these formulæ, we must repeat to the student that W is the breaking weight in tons, a the sectional area of the bottom flange in inches, d the whole depth of the girder in inches, and 7 the length between bearings, also in inches; from the above formula I W we obtain C, which reads, in words, the length multiplied by the ad breaking weight, divided by the sectional area of the bottom flange, multiplied by the depth, equal to the constant C. A sensible difference is found to exist in the strength of girders cast erect or cast on the side, the metal being more dense and pure in 242 CAST AND WROUGHT-IRON GIRDERS. the first, for which the constant, calculated from the breaking weight on the model above referred to, is 26.8 tons, and for the second it is only 25.7 tons. The latter number is always taken in practice for the greater security, and almost always the decimal is left out of the calculation. We must now come to the apportionment of dimensions in cast-iron girders, and, in calculating this, we must repeat that due regard must be paid to the fact that considerable difficulty always exists in obtaining sound castings of large size, and it is almost surprising how very little neglect, how small an accident will ruin a casting; hence the necessity of full dimensions in all cast-iron constructions. It has been experimentally ascertained, that when from one-third to one-half of the breaking weight at the centre is applied to a cast-iron beam, a considerable permanent set takes place, denoting that the clasticity of the metal is affected; and therefore, from twice and a-half to three times the weight calculated for, applied at the centre, which about doubles it, is that which we are to consider breaking weight; and this the more particularly where the girder may be subjected to blows or jars, as in the case of railway girders. It must not be lost sight of, that, in proportioning the dimensions of a cast-iron girder, all the con- ditions to which it may be submitted are to be carefully considered. In practice it is not always possible to bring the refinements of science to bear, but where this is possible, even in a slight degree, it should never be omitted. In Mr. Clarke's History of the Britannia Bridge, the following remarks are made on cast-iron girders :- "But for two practical considerations, the best way to arrange the forms of cast-iron girders would be to consider that the distances from the neutral line of the upper and lower filaments exposed to com- pression and tension in the flanges, should be as the capabilities of the material to bear such strains, and to make the areas of sections from the bottom of the lower flange to the neutral line, and from the neutral line to the top of the upper flange, equal as at Fig. 25. The two considerations which render this inexpedient in practice are, first, the different thicknesses the section would assume, and which, from the difference in the contraction in cooling of thick parts and thin parts, would be unsafe. Secondly, the upper portion, which is exposed to pressure, is in the position of a column, and consequently more likely CAST AND WROUGHT-IRON GIRDERS. 243 to give way by bending laterally than by being merely crushed. Owing to the increase of thickness and breadth hence requisite in the part exposed to pressure, it is unadvisable in practice that the ratio of the amount of pressure to that of tension exceed 2 to 1." Although it is, therefore, inexpedient to give this form of section, we may obtain an approximation to it as regards the bottom flange, as in Fig. 25, by making the rise of the step on the bottom flange equal to about or of an inch. For railway girders of cast-iron the weight usually calculated for is 2 tons per foot of span for each girder, and more when the span is above 40 feet, and this material is used; which, however, is not expedient, nor necessary. For the cast-iron girders of roadways take from 13 to 1.75 tons per square yard of roadway, which weight may be distributed over 5, 6, or 7 girders, as the case may be, including the outside girders. then It has already been pointed out that depth is an important element in a girder. Depth in a beam increases its rigidity, but lessens the elasticity. It is also to be observed that depth increases the height of the column of which we have spoken above, and with the increase of height the liability to lateral flexure increases also. From one-twentieth to one-fifteenth of the span is generally taken for the depth, and more often the latter for railway girders. As an example, take a railway girder for 30 feet span, or 360 inches. 30 x 2 = 60 tons breaking weight. d, the depth = 15)360(24; ΟΙ 600 × a 360 600 a = 21600; 600) 21600 (36 inches for sectional area of bottom flange. If we take for the width two-thirds of the depth, we shall have 16 inches, but, to avoid fractions, take 18 inches, and we shall have the bottom flange 18 inches wide and 2 inches thick. and = 60; As regards the top flange and the web, we may consider their sectional areas together as equal to that of the bottom flange; we have, 244 CAST AND WROUGHT-IRON GIRDERS. therefore, 36 inches of sectional area to dispose of, and if, for this railway girder we apportion one-fourth of this amount to the top flange, we may make it 4 inches by 2 inches=9 inches; this leaves 27 inches for the web, and if we make this 1½ inch thick it will be near enough for practice. There is only to add a few remarks as regards the side elevation of such a girder. When it is not necessary that the flanges should be parallel, a considerable economy of material may be effected by remem- bering that a girder of uniform section throughout contains unnecessary material at all other points, when there is only sufficient at the centre. A girder may be diminished towards the ends, in the pro- portion of the rectangles of the segments at every point. If this diminishing be made in the depth of a girder, the strength decreasing as the square of the depth, the curve will be in the form of an ellipse. It is customary to shorten this operation by making the depths at the ends equal to two-thirds of the depth at the centre, and from these two ends to pass a curve through the central point-this refers to the top flange. A similar diminution is often made in the plan of the bottom flange. In this latter case the tapering towards the ends may assume the form of a double parabola. The end feathers would be about 2 inches thick, and the intermediate ones about 1 inch thick, and about 3 feet apart. Tie-rods 1½ in diameter are bolted to these, connecting the girders together, or lugs may be cast in the same horizontal plane as the bottom flange, and with it, by means of which the same object may be effected. The above laws apply generally to the beams for fire-proof floors of buildings. At the end of the chapter will be found a table of deflections under the passage of trains, which, being of a truly practical nature, is not uninstructive. Riveted plate girders have almost, if not quite, superseded large girders of cast-iron, and will probably in most cases take the place of the latter material altogether. The reliance that may be placed in wrought-iron, and its high tensile powers, would ensure this. There are, however, a few subjects in plate girders which require careful attention and discrimination, the designs of these beams, more particularly for large spans, being more intricate. CAST AND WROUGHT-IRON GIRDERS. 245 I I. Where the top and bottom flanges are both flat, the top flange requires a sectional area approaching to double that of the bottom flange. II. In long girders the thin web is subject to lateral flexure and to buckles, as are all large, thin, flat plates of wrought-iron. III. Judgment is required as to the riveting the covers and the angle iron. With regard to the necessity for making the top flange double in sectional area that of the bottom flange, this expenditure of material may be overcome by making the top curved, either semicircular or of a curvature equal to about the third of a circle in small girders, thereby offering easier means for the riveting. This system of curving the top is due to Mr. Brunel. The first announcement of it which the author met with was in Mr. Clarke's History of the Britannia Bridge, where a record of the experiments made on such a model will be found. This is, perhaps, one of the most scientific and elegant adaptations of a material that we have, for the material exposed to compression is at once brought to act largely by tension. Reference to Fig. 27 will explain this, and to this figure the reader is referred for the explanation of what we have to say about a large plate-girder. We will now take up the subject of riveting, upon which there are many different opinions. In the work already referred to, by Mr. Clarke, we find at page 395 the following remarks : "The pin is supposed well fitted in the vertical holes through the plates. See Fig. 26, by accident marked 20 on diagrams. "It is therefore only necessary to ascertain the forces requisite for shearing a single pin of the given section to ascertain the strength of the whole joint. "The ultimate resistance to shearing is proportional to the sectional area of the bar torn asunder. "And the ultimate resistance of any bar to a shearing strain is nearly the same as the ultimate resistance of the same bar to a direct longi- tudinal tensile strain. 7 8 "A mean of four experiments on the single shearing of bars of rivet iron of inch in diameter was per square inch of section = 24·15 tons. 246 2 CAST AND WROUGHT • IRON GIRDERS. "And on a double shearing as above 221 tons. "The ultimate tensile strength of these bars of rivet iron was found to be 24 tons per square inch; hence their resistance to single shearing was nearly the same as their ultimate resistance to a tensile strain. These experiments were made with a lever to avoid anomalies; by this means two plates § inch thick were riveted together by a single rivet inch in diameter, and the rivet was sheared by suspending actual weights from the plate; the rivet thus sustained 12.267 tons, or 20·4 per square inch. "Three plates united by a similar rivet, and the rivet sheared in two places by the centre plate; ultimate weight suspended from the rivet 26·8 tons, or 32·3 per square inch." In riveting two plates together to resist a tensile strain, the sec- tional area of the rivets should be equal to that of the plates them- selves, if we depend solely on the shearing of the rivet; but as rivets are usually closed in a red-hot state, it is evident that the shortening of the rivet, as it cools down, must tend to draw together the plates united, and before they can slip on each other, the friction thus induced must be overcome simultaneously with the shearing of the rivet itself; hence the value of the rivet is greater than the value determined above, by the amount of friction produced by its contraction in cooling. The contraction of a wrought-iron rod in cooling is about equiva- lent to 10,000 of its length from a decrease of temperature of 15° Fahr., and the strain hus induced is about 1 ton for every square inch of sectional area the bar. Thus, if a rivet 1 inch in section were closed at a temperature of 900°, it would, in cooling, decrease of its length, and, if its elasticity and strength remained perfect, would produce a tension of 60 tons. The ultimate strength of rivet iron being, however, only 24 tons, the rivet would, in cooling, be permanently elongated, and would continue, when cool, to exert a tension of 24 tons, provided its elasticity remained uninjured by the strain. Thus if the rivet were not in contact with the plates, excepting at the head and tail, the plates would be held together by a pressure of 24 tons, and this friction would have to be overcome before the rivet came into action as a mere pin. These reasonings were verified by experiments; it is not, therefore, 60 10,000 CAST AND WROUGHT IRON GIRDERS. 247 1 requisite that the area of the rivet should equal that of the plates united as with a simple loose pin. This close union of riveted plates is a most important characteristic of riveted work, the joints being as immovable as the most perfect weld. Thus also, by judicious riveting, the friction may in many cases be nearly sufficient to counterbalance the weakening of the plate from the punching of the holes, so that a riveted joint may be nearly equal in strength to the solid plates united. From Mr. Fairbairn's Useful Information for Engineers we extract the following, which is given after the details of some experiments as to the strength of riveted joints in the construction of vessels and the boilers of steam-engines. General summary of results as obtained from the foregoing experiments. Cohesive strength of Plates. Breaking-weight in lbs. per square inch. 57724 61579 58322 50983 51130 49281 43805 47062 Mean 52486 Strength of single- riveted joints of equal section to the plates, taken through the line of rivets. Breaking- weight in lbs. per square inch. 45743 36606 43141 43515 40249 44715 37161 Double-riveted joint Single-riveted joint 41590 The relative strengths will therefore be- For the plate A Strength of double- riveted joints of equal section to the plates, taken through the line of rivets. Breaking- weight in lbs. per square inch. 52352 48821 58286 54594 53879 53879 53635 1000 1021 791 248 CAST AND WROUGHT-IRON GIRDERS. It appears then, when the plates are riveted in this manner, that the strength of the joints is to the strength of the plates of equal sections of metal as the numbers In a former analysis it was which gives a mean of 1000: 1021 and 791 1000: 933 and 731 1000: 977 and 761 which in practice we may safely assume as the correct value of each. Exclusive of this difference, we must, however, deduct 30 per cent. in this particular case for the loss of metal actually punched out for the reception of the rivets, and the absolute strength of the plates will then be, to that of the riveted joints, as the numbers 100, 68, and 46. In some cases, where the rivets are wider apart, the loss sustained is, however, not so great; but in boilers and similar vessels, where the rivets require to be close to each other, the edges of the plates are weakened to that extent. From Mr. Fairbairn's Work on the Britannia and Conway Bridges the following extract is made:-" At the commencement it was stipu- lated that the contractors should use the riveting machine in every case where it could be applied; and in order still further to enhance the value of this process, all the parts which could not be reached by the machine were to be riveted with heavy hammers, for the purpose of causing the rivets to fill the holes, and otherwise to make the work as nearly as possible equal to that done by the machine. During the progress of the construction of the tubes for the Britannia Bridge, the machine work was found (according to the opinion of Mr. Mare, the con- tractor), both expensive and inconvenient, on account of the size and great weight of the plates, and the difficulty of suspending them over the machine. These drawbacks were not, however, experienced by Mr. Evans, the contractor for the Conway tubes, who overcame every difficulty by the introduction of powerful travelling cranes, which enabled him to rivet the greater part of the bottom and sides of both tubes by the machine. Mr. Mare, the contractor for the greater portion of the tubes for the Britannia Bridge, adopted a different method, and, by the use of heavy hammers, made the work, if not equal in stability, at least nearly so, to that done by the machine. The CAST AND WROUGHT-IRON GIRDERS. 249 superior quality of the hand-riveting executed by Mare with the heavy hammers, imposed the necessity of using the same means in the hand-work done by the other contractors." It is now proposed to set out the dimensions of a plate girder for a span of 100 feet. The greatest load likely to come upon this beam would be a train of locomotives, which may be taken at 1 ton per foot this will give 100 tons equally distributed over the girder, which will be equal to 50 tons in the centre; and if for safety we take three times this, we shall have 150 tons breaking load in the centre. For a single line of way on two girders, only half this load would bear on each girder; but we have the weights of the girder itself, of cross tie- girders, longitudinal timbers, planking, ballast, rails, &c., so that we may take out the dimensions of the girder to meet a breaking load at the centre of 150 tons. As regards the depth, one-fifteenth of the span is an ordinary rule; but in wrought-iron girders we may take one-tenth for such a span as this to obtain rigidity in the beam; this will be 10 feet = 120 inches = d, and 7, the length = 100 feet = 1200 inches. Then by the formula, and taking the constant C at 75 tons, we have or, or, a d C l or, = W = 75 × 120 × a 1200 9000 a 1200 9000 a = 180000; or, then, a = 20 square inches in sectional area of the bottom flange, and also in the top when curved. = 150; Such a bridge would, however, but rarely be built for a single line of way. If we double our former breaking weight, we shall now have 300 tons for W, the breaking weight; but this is in excess, and we may safely deduct 10 per cent., leaving 270 tons. We shall now have 75 × 120 a 1200 9000 a 1200 9000 a = 324000; S = 150 tons; = 270; = 270; D 250 CAST AND WROUGHT-IRON GIRDERS. or, a = 36 inches of sectional area in flanges, bottom and top, supposing the latter to be curved; if flat, we should require a much greater quantity of material in the top flange. We have now l, d, and a, the length, the depth, and the sectional area. For the width of the beam, we should take two-thirds of the depth but for the following considerations: as these girders must be about 28 feet apart for the double line, unless we have one in the centre, we must have a number of cross-tie-girders to carry the longitudinal timbers for the permanent way; these cross girders will have to be about 5 or 5 feet apart, and will therefore prevent lateral flexure. If the reader sketches these things as he goes on, it will make all very clear. As these cross girders will completely prevent the main girders from bending horizontally in their length, we may take about one-third of the depth, say 3 feet for the width of the beam at the bottom flange; this will be 36 inches in width, and, as we have 36 inches of sectional area, we shall have the bottom flange 36 inches wide and 1 inch thick, which will be made up of -inch plates. We now come to the thickness of the web, or central rib between the top and bottom flanges, and whose function is to keep these flanges at the greatest possible distance apart under the load. If we take once and a half the sectional area of the bottom flange for the sectional area of the web, we shall have th of an inch for the thickness of the central rib or web. It need hardly be added that a plate th of an inch thick, and 120 inches, or more correctly 118 inches, in depth, will require stiffening to prevent all possible lateral flexure, this slender rib being in the condition of a column. We now come to the top flange. 16 In the Conway Bridge the sectional area of the bottom is 491 square inches, and in the top it is 627. Taking this as a proportion, we should have nearly 46 square inches for the sectional area of the top for the beam in question; also it has been shown by several experiments, that wrought-iron strained by tension beyond 15 tons per square inch, or compressed beyond 12, is destroyed for all practical purposes. And, 12:15:36:45. Then 45 square inches we shall assume for the sectional area of the top of our beam. But it is desirable that this extra quantity of material should be as near the top as possible; 45 - 369, and we shall rivet a strip 9 CAST AND WROUGHT-IRON GIRDERS. 251 inches wide and 1 inch thick along the top of the beam, which will give the further advantage of continuity in length, as also all the advantage of double riveting. Reference to Fig. 27 will give the best explanation. We have now the sectional areas of the top, of the central rib, and of the bottom flange, and these must be united by the means of angle- iron, riveting, and butt plates; the angle-irons will be 4-inch thick, and the rivets not less than 4 inches apart; butt plates about thick, with four rows of rivets. It has already been pointed out that the central rib will require stiffening, which will be done by Tangle-irons, 5 feet apart, and stay- ribs, which are shown on the drawing already referred to; there will be two of these stay-ribs 10 feet apart in the centre, and two the same distance apart at each end, and two more midway between the centre and the ends. From the slight dimensions of these stays, they will be somewhat in the same condition as the central rib itself, and will them- selves require stiffening by angle-irons. These details, as well as the means employed for maintaining the top of the girder in its curved form will be most readily understood by reference to the sketch already referred to, if the student will work out elevation and plans. 12 For plate girders of a lesser span, as 30 or 40 feet, the same rules apply, but we should take of the span for the depth of the beam, and the sectional area of the central rib may be equal to that of the bottom flange, the width of which will be about of the depth of the beam; the form of the top will be segmental, about of the circumference op of a circle, to admit of greater convenience in riveting; the planking may be so managed that not more than two stay-plates will be required at each end, and three girders to form the bridge. The following are Mr. Hodgkinson's rules for cast-iron columns:- For solid cylindrical pillars, with ends flat and incapable of motion; Strength in tons = 44·16 × W 44.16 d 3'6 L 17 where 44.16 is the constant, d, the diameter in inches, and L, the length in feet. And, 1.7 × L¹7 = d 3°6: ; s 2 252 TIMBER BRIDGES AND CARPENTRY. that is, in words-the weight in tons divided by the constant 44.16, and multiplied by the length raised to power, 17, equal to diameter in inches, raised to power, 3.6. For hollow cylindrical pillars, with flat ends and immovable; And Strength in tons = 41.3 x where D is the external diameter in inches, and d the internal diameter in inches also, and L the length in feet. In practice, however, perfect fixing is not attainable. For solid pillars therefore the rule is, 14.9 × For hollow pillars, "" 13 × D37 d3'6 "" 1'7 W 14.9 L Strength in tons. Taking wrought-iron at 480 lbs. per cubic foot, the following practical rules will be found convenient :- 17 × L¹7 = √3'6 d37 D36 - d 3'6 L 17 Strength in tons. Sectional area in inches x 10 = weight in lbs. for every yard in length. × length in feet 672 weight in tons. PART III. — TIMBER BRIDGES AND CARPENTRY. Ir, as there is much reason to anticipate, the patent process of the Docteur Boucherie of Paris should be as successful in practice as expe- riments would show, it is probable that the above economical means of spanning wide chasms will be adopted more commonly than they have been of late. The decay to which all timber is liable under many TIMBER BRIDGES AND CARPENTRY. 253 circumstances has not only been the cause of its being much disused, but also vilified; had strict justice been done, it is not the material that should have been blamed, but those who put the timbers together. Many processes have been introduced, which, carried out in their integrity, would greatly contribute to the preservation of timber; but rarely has justice been done in these matters, because deception was comparatively easy. It was but a very few years ago that the writer of these pages had occasion to see some large and well-designed timber trusses, on the designs for which the Engineer had evidently bestowed great pains, and which were to be "Kyanized;" but, alas for human nature! in this case the timber and Kyan's process had never had the most remote contact with each other. In England it is probable that wrought-iron girders will become more common every year; but English Engineers are all over the world, and there are still many countries where it is desirable to use timber, if we can but preserve it from too rapid a decay. Kyan's process consists in immersing timber in corrosive sublimate, or bichloride of mercury. Subsequently closed tanks having been sub- stituted for open ones, and an injecting apparatus with force-pumps, as well as air-pumps for previous exhaustion, having been added, the solu- tion was forced into the timber. It is believed that the solution should not be of less strength than 1 lb. of corrosive sublimate to 9 gallons of water. Burnett's process consists in impregnating the timber with a solu- tion of chloride of zinc. In Bethell's process, oil of tar, creosote, and pyrolignite of iron, "which hold more creosote in solution than any other watery men- struum." Payne's, by sulphate of iron and muriate of lime. One of Bethell's processes consists in placing the timber in a strong iron cylinder, and exhausting the air from it by an air-pump until a vacuum is created, equal to about 12 lbs. on the square inch; the creosote is then allowed to flow into the cylinder, and a pressure is put upon the creosote, by means of a force-pump equal to 150 on the square inch. The timber has then been prepared. An average of 11 lbs. per cubic foot has been used on the Memel timber at Leith 254 TIMBER BRIDGES AND CARPENTRY. harbour works. Piles, 14 inches square, of unprepared timber, at Lowestoft harbour, were shown to have been eaten away to 4 inches square, in 4 years, while creosoted piles of the same dimensions, drawn alongside of them, were intact. We extract the following from the pamphlet circulated by the Permanent Way Company:- "The mode hitherto adopted to impregnate trees has been by saturation only, assisted sometimes by great pressure, and by previously submitting the timber in cylinders to a vacuum or to heat. "Dr. Boucherie's process differs entirely, inasmuch as he applies a moderate pressure, and to one end only of the sap tubes of the tree; the effect of which is to expel the sap by the preserving liquor, which takes its place. (C By the processes hitherto used, the sap (the formation of which is admitted to be the cause of decay) is allowed to remain in the tree; in the Boucherie process the sap is expelled, and the tubes are thoroughly cleansed from the fermenting matter." * * * "Another advantage in Dr. Boucherie's process is derived from the simplicity and small cost of the apparatus, which for small quantities will not exceed £10, or £15, and for a railway of 200 miles under £50." A detailed explanation, with illustrative cuts of the whole process, will be found in the pamphlet above referred to, as well as a detailed account of the experiments made. It is very desirable that further experiments on the transverse and tensile strength of timber so treated should be made. WOODEN BRIDGES AND VIADUCTS. Wood, as a material for the construction of bridges and viaducts, may be selected in preference to stone or brick, on the score of economy, and from the comparative rapidity with which such structures may be erected; but it is of course very inferior to the last-named materials as regards strength and durability; and in designing and constructing such works, the inherent defects of wood must as much as possible be counteracted. Experience has proved that the most simple TIMBER BRIDGES AND CARPENTRY. 255 combinations of timber are superior, for strength, to complicated systems; and these have latterly become almost entirely abandoned. By calculation, a scientifically-framed truss may be made; the almost impossibility in practice of making such a perfect assemblage of the timbers as the calculations would have been based upon, renders such complicated combinations unwise; moreover, to obtain even that degree of perfection of which practice is capable, we must resort to an excess of strapping, bolting, keying, morticing, and every description of jointing, which becomes very expensive, and when we have done all this, the destructive effects of rain, sun, and wind, increase in the very proportion of complication introduced in the system of construction; unavoidably, also, a considerable quantity of material is wasted, which might be profitably reserved for increase of strength under a more simple mode of treatment. The intention of a truss, composed of a multitude of timbers, is not only an equable distribution of the super- imposed weight, but also a dispersion of the shaking and vibration resultant from the motion of weight; this, nothing but the most perfect workmanship could obtain, and all practical men know the extreme difficulty of obtaining this, however great the expense incurred. In Colonel Emy's very clever work On Carpentry, and Dempsey's Timber Bridges, the student will find a variety of systems and combinations; and several useful trusses, with details, have been given in this work. For great spans, the laminated arch is unrivalled for strength and elegance; it is formed of planks laid one upon the other, breaking joint in length and breadth, and bolted together. Colonel Emy, above-men- tioned, claims the invention, in 1819. From the tendency of the planks-which, however, appears to be but small-to spring back to their original straight line, the thrust of such an arch on piers or abutments is no greater than that of a single beam. On this description of arch, originally applied to the construction of roofs, two distinct systems of bridge arches have been based; the one by the superposition of the platform on the laminated arch, and the second and best, by suspension from it. The following note of dimensions of viaducts of this descrip- tion may not be here out of place. : 256 TIMBER BRIDGES AND CARPENTRY. Notes of Dimensions of some Laminated Arches. Name of Viaduct, or Bridge. Ouse Bridge, East Anglian Railway Dinting Vale, Shef- field and Man- chester. Wellington, Dean, Newcastle, North Shields, and Tyne- mouth Railway Ouse Burn, do., do., Railway West Durham Sechill - Newcastle upon - Tyne and North Shields Span in Name of Engineer. feet and inches. J. S. Valentine. 121,6 A. Jee. J. & B. Green. The same. The same. R. Nicholson. The same. 125,0 120,0 116,0 Rise in feet and inches. 52,6 14,4 25,0 36,0 32,6 79,0 13,0 81,6 8,9 Thick- ness of Rib in feet and inches. 3,8 4,6 Width of Rib in feet and inches. 2,9 2,2 2,4 3,9 1,10 3,6 1,10 2,3 1,5 2,3 1,5 7,0 1,9 1,5 In the Sheffield and Manchester, Willington Dean, Ouse Burn, and West Durham, the platform of the railway is supported by struts or spurs, which rest upon the laminated ribs, which abut on cast-iron bed-plates resting on stone piers; there are three ribs in each arch. In the Sechill and North Shields, in which the laminated arches form flat segments, the platform is suspended from the arch by wooden ties strapped to the arch, and braced together laterally; the rib springs from a joggled cast-iron shoe, resting on the platform which surmounts stone piers. In the Ouse Viaduct, on the East Anglian Railway, the platform is also suspended from the laminated rib; but, most judiciously, the Engineer has suspended the platform by means of wrought-iron rods. The drawings, for which we are greatly indebted to Mr. Valentine's courteous liberality, are far preferable to any description we could give, TIMBER BRIDGES AND CARPENTRY: 257 and we will close the subject by referring the student to them, and annexing a few observations which appeared in the Railway Chronicle:- "The Viaduct over the river Ouse is 150 yards long, and consists of ten side openings of 30 feet span each, with a single span over the waterway of 121 feet 6 inches. The method adopted to support the roadway over this great space is by suspending the platform from three timber bows, each formed of 3-inch deals, firmly united together by oak trenails; the suspension rods are of wrought-iron of the very best material and workmanship; each rod has been proved to be equal to a strain of 20 tons, and as there are 72 of these rods, the weight they are capable of supporting is 1440 tons; but the greatest weight which they will be required to carry will not exceed 310 tons, the platform itself being 160 tons, and the greatest load that can be placed upon it being about 150 tons. The piers upon which the superstructure rests are built of Yorkshire stone, the foundations resting upon the solid gault at a depth of about 30 feet below the top of the banks. Minute and careful admeasurements were taken by the Government Inspector to ascertain the strength of this bridge. Four locomotive engines and tenders, and five wagons loaded with iron, were placed upon it at the same time; but scarcely any deflection of the beams was perceptible; and whether the trains were at rest on the bridge, or passing over it at full speed, there was not the least perceptible difference." The drawings of the Ouse Bridge are so perfectly detailed that no difficulty can occur in setting out any design of this description, by copying or changing, as future experience may suggest. The above note of dimensions will also be some guide in deciding on the number of planks of which the rib is to be composed. At present, as far as we are aware, 125 feet is the greatest span we have in this description of arch. The Ladykirk and Norham Bridge over the Tweed, J. Blackmore, Engineer, is composed of two arches of 190 feet span each, rise 17 feet. Each arch consists, first, of a rib of three thicknesses of 6-inch planking at the crown, and the number of thicknesses is increased one by one towards the springing, where the thickness of the rib consists of 8 courses of 6-inch planking; above this arch comes the platform, resting on the summit of the above rib; about 7 feet above the platform comes 258 TIMBER BRIDGES AND CARPENTRY. another rib, of 110 feet span, and of about 5 feet rise, the springing of this second arch being over the middle of a centre pier 20 feet thick; this second rib consists of 7 courses of 6-inch planking at the crown, diminishing one by one towards the springing, where it consists of a single plank; the ribs are connected by 14 struts, each strut strapped at top and bottom to the ribs, and there are 14 braces connecting the struts; these struts and braces abut both on the upper and lower ribs at the increase in thickness of planking. This design possesses the merit of originality, but we have only introduced this short description of it on account of the great span, and to suggest that in a similar case the upper rib be brought down and united to the lower one, and that it be formed of 3 instead of 6-inch thicknesses; the rib, however, should be made 5 feet 6 inches thick, and 1 foot 6 inches broad. Where the rise is only one-fifth or less of the span, an increase of thickness at the springing is unnecessary. The openings of viaducts are seldom under 30 feet, and as wood is not used for elegance or durability, but from motives of economy, it is fortunate that a very simple construction answers every purpose required; we mean that shown in continuation of the Ouse Bridge. It has been very extensively used, and experience therefore recommends its continuance. In the drawings referred to, all that is wanted for the setting out of working drawings will be found. The reader will remember that strength of connexion between the trusses transversely is quite as necessary as the strength required in the form of the truss itself, and this will be effected by transverse ties and braces. FIG. 28. A few words on details may be of some service. Timbers are connected by various descriptions of joints, the most simple being generally the best, particularly for our pur- poses. Fig. 28 shows tenon and mortice; T the tenon, M the mortice. The thickness of a tenon is made one- third the thickness of the timber on which it is cut, and the size of the mortice of course corresponds to the dimen- sions of the tenon; the depth of a mortice should exceed a little that of the tenon; as the perfection of the work, so is the value of the joint; the shoulders of the tenon should be exactly in one place, and perfectly perpendicular to the T M PR TIMBER BRIDGES AND CARPENTRY. 259 axis of the timber; where, acting by suspension, little depth is required, if a strap be added; otherwise an oak trenail should be driven through the timbers, the holes being bored after the tenon is in the mortice. The diameter of a trenail should be one-fourth the thickness of the tenon, and the hole bored for its reception should be at two-thirds from the end of the tenon, as shown in the figure; but the value, as regards the strength of a tenon and mortice, should be independent of the trenail. The above is a rectangular mortice and tenon. Fig. 29 shows an oblique joint of this description, and it is believed explains itself. The above description of joint, though common, is not the best of the kind, the timber T being weak at a, and liable to fly; Fig. 30 is a better system, FIG. 29. Милинка 1 FIG. 30. X AF T M ww M AW es where T is partly joggled into M, and s a is made from about one-fifth to one-fourth of the thickness of the piece M. In setting out a joint of this kind with a single joggle and no tenon and mortice, to find the direction of s a, Fig. 31, draw the central axes of the timbers, and os will give the direction of sa; or divide the 260 TIMBER BRIDGES AND CARPENTRY. angle as b, and the line sv will give the direction of sa'; or make s a perpendicular to sb; or from c as a centre with radius c s, describe an arc, on which set off from one-fourth to one- fifth of the thickness of the timber M; it must not be forgotten that too sharp an angle at a is likely to make M fly at . To find the direction of s a, in timbers abut- ting end to end, Fig. 32, divide the angle a xs, which will give the direction of sæ. It is always expensive to obtain tim- bers of large scantlings and great length; and when a beam beyond 24 feet or there- abouts is required, we have generally recourse to scarfing, which, it is unne- cessary to add, is a joint in which the ends of the timbers are cut and over- lapped so as to form one in appearance. Some persons are partial to complicated scarfs, but we have no greater faith in them than in complicated trusses, much for similar reasons, and because so much hacking of the timbers must weaken it; also they become very expensive. In a scarf, it is evident that the bearing surfaces have to support the strain, and therefore the greater the quantity of surface the greater www чому I M FIG. 31. xxx a 1 1 T a www. FIG. 32. X 1 3 N the strength, provided the best form be given; therefore, also, a long scarf is stronger than a short one, for the same reason that any TIMBER BRIDGES AND CARPENTRY. 261 4 strength at all is gained by a scarf, but a great waste of timber and much workmanship are involved. One important consideration, and which should never be lost sight of, is the strain to which a scarf will be exposed, compression or tension. Scarfs are greatly strengthened by iron bolts and oak keys. Where the surfaces of the scarfing are square, iron bolts are preferable to keys, and the contrary where the jointing surfaces are oblique to the fibres of the wood. Let Fig. 33 be a beam Ն FIG. 33. d 11 π W scarfed at W, where it is exposed to a strain from the weight W. The upper portion of the beam is exposed to compression, the rectangular bearing a, is therefore the most appropriate, as an acute angle formed by a line parallel to 6, would, on the beam being compressed, act like a wedge, and tend to make the upper portion of one beam fly; but this is reversed at 6, which would tend to open by tension. Of the keys c and d, the first would be under compression, and the latter would be loosened; but being near the neutral line, the tightening and loosening would be comparatively small, unless the beam were loaded beyond the bounds of prudence; also c, under compression, would tighten the beam at a, and though d would not do the same at 6, the bevel joint must pre- vent any evil results. Whether we have one, two, or more keys, the single or aggregate depth should not exceed one-third the depth of the beam, neither should they be too violently tightened when driven. This scarf is short, and we may add considerable strength by a bolt at W; and it 11 !! FIG. 34. a 11 would be better still to place a bolt at c and at d, and the key in the centre, as at Fig. 34. Fig. 35 is strong enough for most purposes. It need 262 TIMBER BRIDGES AND CARPENTRY. scarcely be observed, that the further the scarf may be from the points of bearing, the greater the strength required; bolts should never be It U 6 16 #f " FIG. 35. 41 (6 placed too near the end of a beam. Wrought-iron straps are great auxiliaries of strength, and may be very advantageously used in con- necting timbers, whatever may be the joint, provided always that tension be the strain to be resisted. It has been very cleverly remarked, that a skilful carpenter never employs many straps," &c. ; but however skilful a carpenter may be, he cannot prevent the effects of atmospheric influence, neither can he give to comparatively new wood the properties of well-seasoned timbers. No man who knows anything about design- ing in wood, would consider straps as principles of strength in his constructions; but as fastenings, as auxiliaries, they are perfectly admissible, of course in moderation, and are becoming daily more in Before use, straps, and indeed all ironwork, should be heated to a blue heat, and struck over with raw linseed oil; this is far preferable to paint as preventive to rust, and is in accordance with the practice of Smeaton. A strap 1 inch wide may be made thick; 13 wide, thick use. ; 1 4 2 inches wide, thick. Cast-iron plates and shoes are also very useful to receive or to equalize the thrust from the ends of butting timbers, the first particularly, where employed as a connecting surface between the ends of timbers, which, from shrinkage, defect of workmanship, or otherwise, may come to bear upon opposite angles, instead of the whole area of their intended connected surfaces. This subject may now be concluded by practical illustrations of the rules for ascertaining the strength, or determining the scantlings of timber. To ascertain the cohesive strength of timber, or the tension it will bear, when the weight acts in the direction of the axis of the timber, multiply the area in inches by the proper tabular number in the table of specific gravities. TIMBER BRIDGES AND CARPENTRY. 263 To find the weight that will tear asunder a piece of fir 4" x 4"; we have here 16 square inches, and the tabular number is 9500; then 9500 × 16 = 152,000 lbs., one-fourth of which would be taken in practice for a perfectly safe load, or 38,000 lbs. Having the load, to find the scantling, divide the load by the tabular number; as, let the load be 38,000: 3000 4", for the side of the scantling. 9500 To find the strength of a beam fixed at one end and loaded at the other, multiply continuously the sectional area by the depth, by the constant of strength in the same table as the former constant, and divide by the length, all in inches; if the beam is inclined, the length will be the horizontal distance between the ends, of course not including the quantity of bearing, as of tailing into a wall. To find the strength of a beam of Memel 10 feet long, 5 inches wide, and 7 inches deep; 5 x 7 = 35 sectional area; 35 x 7 depth = 245 × 1730, constant of strength = 416850; and this divided by the length in inches gives 3473 lbs. nearly; but this would be the breaking weight, only one-third of which should be taken, or 1157 lbs. as the weight to be borne without straining the timber; and twice this load may be taken if the weight is to be distributed over the beam. Given the depth, and length, and the load, to find the breadth; as above, let the length be 10 feet, the load 1157 lbs., the depth 7; and the timber of the same description; multiply continuously the weight by 4, by the length in inches, and divide by 1730, the constant multi- plied by the depth 7; the product will be the sectional area, which divide by the depth 7. = Given the breadth, the bearing, and the load, to find the depth; multiply the weight by 4, by the length in inches, and divide the product by the constant multiplied by the breadth; and the square root of the quotient will be the depth. To find the strength of a beam fixed at the ends and loaded in the middle; multiply continuously the breadth × 6 × the square of the depth by the constant, and divide by the length; as to find the strength of a beam of Riga 20 feet long, 13 inches square, we shall 13 × 6 × 132 × 1050 57671 find =19223 lbs. in the middle, and twice 240 3 this distributed over the beam. 264 AQUEDUCT BRIDGES. The above rules are for permanent weights. We may shorten the calculations by dividing any of the constants by 3, which will save the trouble of reducing the feet to inches; in the column for constants of elasticity, this has been done; calculations of this kind are generally made with the constants so reduced. The above rules are mostly according to Professor Barlow's formulæ ; and the constants are obtained by the formula the constant, Z W 4 b d 2 where 7 is the length in inches, W the breaking weight, b the breadth, d the depth. 7″. A batten is 2″ × A deal is 3″ × 9. A plank is 3" x 11"; above this size flat timber is termed a slab. Scantling is a term used to express sectional dimensions of timber; it is also applied to quartering under 5 inches square. Logs are about 13" square and under. A balk is above 13" inches square. PART IV. AQUEDUCT BRIDGES. AMONGST other works of construction connected with railways, the Engineer has occasionally to design aqueduct bridges, as where the line of railway crosses under a canal. This style of bridge does not occur as commonly as other bridges, but requires special precautions, as we have to make a line of way for water and the passage of boats instead of carriages or railway trains, and this line of way must not only be water-tight when the works are completed, but continue so afterwards. Generally these works are rather more expensive than ordinary LEGAL REGULATIONS AS TO RAILWAY BRIDGES. 265 bridges; the canal is usually diverted temporarily during the construc- tion of the bridge; provision has to be made for a towing-path as well as the waterway of the canal itself; and almost always we are guided as to dimensions not only by those of the canal as existing before the passing of the Act, but very often by clauses provided by the special Act. It will readily be perceived how necessary it is that an aqueduct bridge should be water tight, not only as regards the water itself, which might escape, but also the gradual process of decay in the bridge, which would ensue from the filtration of water through the materials. Where the bridge is of brickwork or masonry, it is highly important that sufficient time be given for the complete settlement of the arch after the centres are withdrawn, before any other work is commenced. Plates 17, 17A, 18, 18A and 18в show the working drawings of two aqueduct bridges; the one in brickwork, the other in cast-iron, for which wrought-iron may be substituted; the two latter afford the readiest means of making the bridge water tight. At the junction of the bridge with the adjoining earth great pre- cautions are requisite to prevent leakage, which almost always ensues after settlement; a puddle of fine gravel and lime may be employed to check this, and will be found to adhere both to the ordinary puddle and the masonry itself. PART V. LEGAL REGULATIONS AS TO RAILWAY BRIDGES. WE have now gone through the subjects of the arch and of retaining walls, cast and wrought-iron girders, and timber trusses, and aqueduct bridges; we have only to add that in getting out working drawings, the work should be done as if on the ground, and the reader is referred to the chapter on "setting out works," where it is hoped ample rules will be .found to meet most cases. No discrepancies would then occur between the works as designed and as carried out. T 266 LEGAL REGULATIONS AS TO RAILWAY BRIDGES. This part of the subject will be concluded by a short abstract of legal enactments on this part of our subject. "The width of the arch shall be such as to leave thereunder a clear space of not less than 35 feet if the arch be over a turnpike road, and of 25 feet if over a public carriage road, and of 12 feet if over a private road. "The clear height of the arch from the surface of the road shall not be less than 16 feet for a space of 12 feet if the arch be over a turnpike road, and 15 feet for a space of 10 feet if over a public carriage road; and in each of such cases the clear height at the springing of the arch shall not be less than 12 feet. "The clear height of the arch for a space of 9 feet shall not be less than 14 feet over a private carriage road. The descent made in the road, in order to carry the same under the bridge, shall not be more than 1 foot in 30 feet if the bridge be over a turnpike road, 1 foot in 20 feet if over a public carriage road, and 1 foot in 16 feet if over a private carriage-road, not being a tramroad or rail- road, or if the same be a tramroad or railroad, the descent shall not be greater than the prescribed rate of inclination, and if no rate be pre- scribed, the same shall not be greater than as it existed at the passing of the special Act. "Every bridge erected for carrying any road over the railway shall (except as otherwise provided by the special act) be built in conformity with the following regulations :- "There shall be a good and sufficient fence on each side of the bridge of not less height than 4 feet, and on each side of the immediate approaches of such bridge of not less than 3 feet. (C ܢ܆ - The road over the bridge shall have a clear space between the fences of 35 feet if the road be a turnpike road, and 25 feet if a public carriage road, and 12 feet if a private road. "The ascent shall not be more than 1 foot in 30 feet if the road be a turnpike road, and 1 foot in 20 feet if a public carriage road, and 1 foot in 16 feet if a private carriage-road, not being a tramroad or railroad. "But it is provided, "that in all cases where the average available width for the passage of carriages of any existing roads, within 50 yards of the points of crossing the same, is less than the width herein before LEGAL REGULATIONS AS TO RAILWAY BRIDGES. 267 prescribed for bridges over or under the railway, the width of such bridges need not be greater than such average available width of such roads, but so, nevertheless, that such bridges be not of less width, in the case of a turnpike road or public carriage road, than 20 feet." SPECIFICATION OF BRIDGE OVER THE RIVER OUSE AT HILGAY. J. S. VALENTINE, ESQ., C.E. The foundations for the piers shall be excavated to the depths and widths shown upon the drawings, or as much lower as the Engineer may consider necessary from the nature of the ground. Previous to commencing the foundations, the bottom of the trenches shall be made perfectly dry and level, for the reception of the planking. The space around the foundations, to the height of the present surface of the bed of the river, shall be filled in with sound gault, as the work proceeds, and well rammed in layers not exceeding 6 inches in thickness. thus, STONE. The whole of the stone to be used in the piers shall be from Bramley Fall Quarries, and of the size shown upon the drawings, and each stone shall be laid upon its natural bed. The size and bond of the stone in each course are shown with blue and brown lines in drawing No. 6 d, and this method of laying the work must be strictly adhered to. The face of the stone-work, from the surface of the planking to within 4 inches of the ground line, shall be rough quarry scappled, with the beds and vertical joints truly worked. Each of the footings shall be in one thickness of stone, and each course shall not have less than three bonding stones. The courses marked in the drawings Nos. 6 a, 66, shall be finished with their own natural face, and each stone shall have a tooled margin, worked round the edge 1 inches wide, 3 SUGASIN ENGHAR 小 ​. 3 79 268 LEGAL REGULATIONS AS TO RAILWAY BRIDGES. The curved part of each of the courses shall be roughly picked and finished with its own natural face, and each stone shall have a tooled margin as before described. The courses, marked A and C on the aforesaid drawings, shall be neatly tooled, care being taken that the stroke shall be in the direction of the weather current, and not less than seven strokes in an inch. The centre string and the upper facia shall be weather throated. The springing course shall be dowelled together with slate plugs, 7" x 3" x 3" as shown upon the drawing. Two copper cramps in each joint of the last-named course shall also be inserted and securely let in with lead. The cast-iron shoes for the reception of the ends of the bows shall have their flanges let flush into the cap stones of the piers. They shall be bedded on lead, and bolted down in the manner shown on the drawing, and when fixed, the joints round the edges shall be well caulked with lead. All the beds and joints of the piers below the ground line shall be made close, and well flushed in with strong lime grout. The joints above the ground line shall also be worked close, and shall be laid and neatly pointed with fine beaten mortar. All bolts and iron work shall be properly fixed in the manner shown upon the drawings. The lime to be used shall be fresh-burnt, and of the best quality of water lime from Stoke or Isleham, or such other place as shall be approved by the Engineer. The piers shall, at the completion of the bridge, be neatly and truly cleaned down, and finished entirely to the satisfaction of the Engineer. CARPENTRY. All the timber to be used for these works shall be the very best Memel or Dantzic fir, free from sap and shakes, large and loose knots, or any other defects, and shall hold, when finished, the several scantlings figured on the drawings, and be framed together in the manner thereon denoted, and the whole of the works shall be executed in accordance with the Specification for timber bridges generally, hereinafter written. The arched ribs shall be made to the proper radius. The two outside ribs shall be 3 feet 8 inches, by 2 feet 2 inches, and LEGAL REGULATIONS AS TO RAILWAY BRIDGES. 269 the centre rib 3 feet 8 inches, by 2 feet 9 inches, they shall be formed with Dantzic deals, dressed on the sides and edges, and in the longest lengths which can be procured. These deals shall be of the very best quality, perfectly sound and well seasoned, and they shall be submitted to the Engineer, and approved by him, before they are used in the work. thus, Each deal shall be bent over the one below it in such a manner as to break joint alternately both ways, and no two end joints shall come over each other, or within three feet of the joint below it. The first course shall be three deals in width, and the next two whole deals and two half deals, and so on till the rib is formed. Each course of deals shall be covered with a coating of marine glue, which shall be applied hot, and in such manner as the Engineer shall direct. The whole of the deals shall be fastened together with the best compressed oak trenails one inch in diameter, made by Messrs. Ransome and May, of Ipswich, which shall be placed four feet apart :- о O O O с each trenail shall be of sufficient length to pass through three deals, and each course shall be trenailed to the two under courses. The greatest care must be taken in fitting the ends of the deals to the abutment plates that they fit perfectly close, and true on their ends, and the ends of all the planks shall abut perfectly square, and true upon each other throughout the bow. The longitudinal beams shall be of the lengths shown upon the drawings, No. 6 c, and scarfed together in the manner shown on drawing No. 6f. The surface of the beams which are bolted together shall be wrought perfectly true, and a coating of marine glue shall be laid between them in the manner described for the bows. The whole of the diagonal braces shall be accurately cut to the exact length, and carefully fitted into the iron shoes. The joists for the roadway shall be 12 inches by 9 inches, and they shall be each of them in one length, and extend across the whole of the 270 LEGAL REGULATIONS AS TO RAILWAY BRIDGES. longitudinal beams, upon which they shall be notched, and bolted down in the manner shown upon the drawing, and the ends shall be neatly finished to such form as shall be directed. The bearers for the rails shall be 12 inches by 6 inches, bolted to the joists in the manner shown upon the drawing, the space between the bearers shall be laid with Dantzic deals 11 inches by 3 inches, spiked to the transverse beams with spikes 7 inches long, and inch in diameter; there shall be two spikes at each joist, and four at the heading joists, and no two heading joists shall come together on the same joist. The towing path shall be carried under the centre opening of the bridge on cast-iron brackets in the manner shown upon the drawings. The viaduct at each end shall be built in the manner shown upon the drawings, and of such dimensions as are there given. IRON WORK. The whole of the iron to be used in this viaduct shall be of the very best quality. Previous to the order for the iron work being given, the Engineer shall certify his approval of the foundry for the castings, and also the manufacturer of the whole of the wrought-iron work. The castings shall be made perfectly true, and of the exact size and dimensions shown on the drawings. The suspension rods for the platform, together with the whole of the bolts, straps, spikes, &c., shall be of the very best quality of scrap iron, and of the dimensions shown upon the drawings, and each suspension rod shall be tested to a weight of 20 tons. The thread of the screws of all the bolts shall be engine cut, and of the very best description of workmanship, which shall have been submitted to and approved by the Engineer, and all bolts which have screws not cut perfectly clean and true, will be at once rejected. The greatest possible care shall be taken that the heads of all the bolts shall be perfectly sound and true, and of the full dimensions shown on the drawings. All the iron to be used in this bridge shall be heated to about a blue heat, and the surface then struck over with raw and linseed oil to prevent rust. The Contractor must take upon himself the entire responsibility of LEGAL REGULATIONS AS TO RAILWAY BRIDGES. 271 the whole of the works during their erection, and must at his own expense erect good and substantial coffer dams, for the purpose of getting in the foundations of the piers, which shall effectually keep out the water from the foundations during the time of their erection, and after the completion of the work the piles used in forming the coffer dams shall not be drawn, but shall be cut off at the level of the bed of the river, if not otherwise directed by the Engineer. All piles which may be used for the purpose of scaffolding or other temporary works shall be drawn upon the completion of the works. The bed of the river shall be excavated to the depth shown upon the drawings, and to such extent, and in such manner as is stated in the Act of Parliament for this Railway. And the barrier banks on each side of the river shall also be strengthened in accordance with the Act of Parliament. During the execution of the work the Contractor shall not in any way obstruct or impede the navigation of the river or the towing paths thereof, but shall in all respects comply with the several clauses in the Lynn and Ely Railway Act, for the preservation of the Drainage and Navigation of the Bedford Level, and all other clauses relating to this river. And he shall also be responsible to the Engineer who may be appointed by the Corporation of the Bedford Level to superintend the works for the due and proper performance of such works, and for complying with the several clauses above referred to. A PART VI. TABLE I. OF SPECIFIC GRAVITIES, WEIGHT PER CUBIC FOOT, AND CUBIC FEET PER TON, OF MATERIALS, With Cohesive Strength, and Constants of Elasticity and Transverse Strength. The authorities are G. Rennie, Esq.; G. Rennie, Esq.; T. Tredgold; Professor Barlow; J. Bramah; Rondelet, and the Report of the Commissioners appointed for examining the different Quarries in England, &c. &c. NAME OF MATERIAL. Alder Ash Do. dry heart-wood Basalt Do. Beech Do. Do. Birch. Do. Bismuth •P Boxwood, from Do. to Brass, cast Do. wire Brickwork (new) Do. (old) Do. in cement. Red Brick Specific Gravity. TABLE OF SPECIFIC GRAVITIES, &c. Weight per cubic foot. *555 34.68 *758 47.37 •845 52.81 3.000 187.50 2.478 154.87 Cubic feet per ton. 64.58 47.28 42.51 *854 53.37 41.95 *720 45.00 49°77 *696 43.50 52'18 *720 45'00 *792 49.50 45.25 9.822 613.87 3.64 59.31 *949 1.328 83.00 8.396 524.80 8.544 534.00 1.872 117.00 1.520 95.00 1.920 120.00 2.160 135.00 Cohesion in lbs. per square inch. Tension. } 15000 11000 19000 18000 Pressure. 82000 Constant of Elasticity. 205000, or 113 169200, or 92 205000, or 113 ! Const. of Transv. Strength. 2020 1560 · } REMARKS. This timber is little used in carpentry, and unless con- stantly and perfectly dry decays rapidly; it is in great demand among wheelwrights; the total height of the tree averages 60 and 70 feet. Beech is very durable if kept constantly wet, and being also hard, forms excellent piling; in building it is not much used; the average height of the trunk is 45 feet, and the average diameter 2 feet. 1928 Birch and Alder are both suit- able for hydraulic works, but both decay easily if exposed to damp, and therefore they are unsuitable to carpentry. One cubic yard of brickwork in cement, may be calculated to weigh about 3284 lbs. and in 274 Do. common (about) Do. London stock Do. Welsh fire. Chalk. Do.. Do. Dorking Cedar (Indian) Do. from. to. Cement Clay, from to Chestnut (sweet) Coke · Coal, Glasgow. Do. Kilkenny Do. Jarrow, Newcastle Do. Garesfield, do. Do.Wigham Banks, do.] Do. Wigan, Lancashire Do. Cannel Coal, do. Copper, cast Do.. wrought Do. wire 1.760 110'00 1.840 115.00 2.408 150*50 2.315 144.68 15.41 2'656 166.00 13.49 1.872 117.00 19.14 1.315 82.18 *453 28-31 *753 47.06 1.600. 100.00 22.40 1.920 120.00 18.66 135.00 16.59 2.160 *696 43.50 *755 47.00 1.286 1.526 1.266 80.30 95.30 79.10 80.00 81.37 82.43 79.50 8.800 550'00 8.915 557.20 8.880 555.00 1·280 1.302 1319 1.272 500 1200 500 19000 57000 33000 51000 mortar 2996 lbs. The crush- ing weight on pale red brick, or rather soft, is 500 lbs., on hard red, 807 lbs., on fire-brick about 1710 per square inch. The adhesive power of good cement, when the power tend- ing to rupture is parallel to the joint, is about 500 lbs. per square inch. This timber was much used some centuries since, and is very durable if properly used; the roof of Westminster Hall and that of King's College, Cam- bridge, are constructed with Chestnut. Average height of trunk, 40 feet, average diameter 2 feet. The relative heating powers of different coals have been pro- portioned as follows:- lbs. of water heated from 32° to 212°. Name of coal. Dowlas in Wales. Newcastle. 72.0 70.0 56.4 64.1 Cannel, Glasgow. Wigan, Lan- cashire. "" 275 NAME OF MATERIAL. Earth, from to Ebony, American Indian Do. Elm Do. Fir, Christiana Do. Norway Do. Memel Do. American Do. Riga Do. Scotch Glass, from. to • → V Specific Gravity. *688 •577 *590 *553 1·520 95.00 2.016 1·328 1216 *553 *543 *738 •693 TABLE OF SPECIFIC GRAVITIES, &c.-Continued. Cohesion in lbs. per square inch. 2.824 2.520 Weight per cubic foot. Cubic feet per tou. 23.57 126.00 17.77 83.00 76.00 34.56 64.93 33.93 66.01 52'09 43.00 36.06 62.09 36.87 53* 34.56 64.71 46.12 48.56 51.72 43.31 187.00 157.50 Tension. 9500 · Pressure. 1200 1800 Constant of Elasticity. 87400, or 50 92750, or 5-1 198700, or 115 182000, or 105 200000, or 115 274000, or 158 124000, or 71 108700, or 62 ↓ Const. of Transv. Strength. 1010 1118 1562 1470 1730 1100 1050 1262 53.2 • REMARKS. Lancashire. The Elm is seldom used in build- ing, but is noted for its dura- bility under water; it was used for the piles of Old London Bridge; average height of trunk 44 feet, and diameter 2 feet 8 inches. There are two sorts of fir, red or yellow, and white; the red is the most durable in any situa- tion, and the best of this kind is generally from Norway; it is imported in logs and deals; the tree (Pinus Sylvestris) seldom exceeds 18 inches in diameter from Norway, and 2 feet from Russia. White Fir (Pinus Abies) is imported from Chris- tiana in planks and deals, and also from America. It was said by Brindley that Red Riga would last as long as oak in any situation. - 276 Granite, Aberdeen red × 'do. blue Do. Do. Do. Do. Do. Do. do. a do. a do. a Do. Blackburn a Do. Manley a Do. Tamor a Do. do. a fine grained Specimen a do. grey Anglesea. Do. % Dartmoor Do. Guernsey Do. × Heytor Do. Talacre Do. × Penryn Do. Peterhead Gravel Indigo Iron, cast Do. Native Do. bar Do. do. Do. do. Do. Swedish Do. Wire 2.643 2.608 2.664 2.704 169.00 2.708 2.708 2.708 2.432 2.256 2.649 165.20 13.55 163.00 13.73 166.50 13.45 13.25 169.25 13.23 169.25 13.23 169.25 13.23 14.73 15.88 165.62 13.23 6.723 7.600 7.787 152. 141* 3.049 190.62 11.75 2.664 166.50 13.45 2.999 187.47 11.96 2.555 159.75 14.02 2.401 150.80 14.85 2.736 171.00 13.10 2.432 152'00 14.73 1.760 110.00 *769 48.10 7.104 444.00 420.18 475* 486.70 5.04 5.33 4.71 4.27 19000 56000 .67600 72000 78000 7100 9200 + 6700 7162 a 11590 9990 6790 4975 2715 5741 11200 7800+ 10300 a 8700 + 4700 a 5700 + 7600 14560 2252000, or 1303 a The numbers under the column "pressure" are from experi- ments by G. Rennie, Esq., and the late J. Bramah, Esq.; a are the pounds borne, × the pounds which fractured, and the others the pounds which crushed the specimens. 7600a a These constants will of course be understood to apply to rec- tangular bars. According to Duleau, wrought 3333 iron may be extended to of its length without injuring its elasticity. Lavoisier and La- place found by experiments that wrought-iron at 32° mea- suring 1 expanded at 212° to 1·00122048; Smeaton found 1001258. For cast-iron, Ge- neral Boy found 1'0011094. • 277 278 NAME OF MATERIAL. Larch Do. Lead, cast Do. milled Lime Specific Gravity. *522 *560 11.352 11.407 ⚫843 TABLE OF SPECIFIC GRAVITIES, &c.-Continued. Cohesion in lbs. per square inch. Weight per cubic foot. 32.62 35.00 · 709 50 712'93 52.68 Cubic feet per ton. 68.66 64° 3.15 3.14 42.52 Tension. 1782 Pressure. Constant of Elasticity. 112000, or 65 131600, or 76 Const. of Transv. Strength. 832 1149 1 Larch is a valuable timber, being strong, hard, and durable; it has in all ages been much esteemed, and is one of the best for hydraulic works; it is said that the ancient city of Ravenna was entirely founded on larch piling; there is no doubt that it is admirably adapted for the construction of wooden bridges and viaducts, but it has not as yet been much used for this purpose, having but lately been grown to any extent in Britain; it bears exceeding well the driving of bolts and spikes; every one knows how commonly it is used for railway sleepers. thick lbs. 1 foot super.milled lead= 3.71 1 = 4·95 ΙΣ "" "" رد REMARKS. "" "" در "" "" "> 23 1 ΤΟ 120~1~|| छ = 5.93 7.41 9.9 14.85 Limestone, from Do. Do. Beer quarry, Devon 2.108 Do. Chilmarks, Wilts. 2.457 Do. Hopton Wood, Derbyshire 1.856 116.00 2.536 158.50 Do. Seacombe, Dorset 2:416 • 131.75 17. 153.58 14.58 2.536 158.50 14.08 151·00 14.83 35.00 Do. Sutton, Glamor- ganshire. 2.176 136.00 Mahogany (Spanish). *852 53.00 Do. Honduras *560 Marble, White, fine grained, compact Do. white 2.840 177.50 2.720 170.00 Do. mercury (fluid) 13.568 848·00 2.641 16.47 17300 on com- pact spe- cimens. 10080 9680 6058 1 TI 32 feet cube of lime = one hundred of lime, containing 25 bushels, and the measure is 3 feet square, and 3 deep. Generally, according to Smeaton, those limestones, into which clay enters as a component are the best adapted for hydraulic works. Light brown; friable; chiefly car- bonate of lime; 6 × 3 × 2. Light greenish brown; carbo- nate of lime with a propor- tion of silica; blocks from 10 cwt. to 3 tons; Salisbury Cathedral and Wilton Abbey; generally in excellent condi- tion. Warm grey; compact; carbonate of lime; blocks of 100 feet cube varying in depth from 3 feet to 10 feet; Belvoir Castle, Chats- worth, Drayton Manor. Light brown; semi-compact car- bonate of lime; 6 × 2 and 4 × 3. Light-houses, piers, and docks. - Light creamy; compact and highly crystallized carbonate of lime; blocks of 6 tons and upwards; thickest bed 12 feet. In many ancient buildings in Glamorganshire and the adja- cent counties. 279 NAME OF MATERIAL. Mortar, from (old) to (new) Magnesian Limestone, Bolsolver, Derbysh. | 2:427 Do. Brodsworth, Don- caster, Yorkshire. 2.138 Do. Cadeley, Doncas- ter, Yorkshire Do. Huddlestone, Sher- burne, Yorkshire Specific Gravity. Do. Smawse, Tadcaster, Yorkshire 1414 1.903 2.025 2.205 Do. Parknook, Yorks. 2140 Do. Roach Abbey, Baw- try, Yorkshire 2.225 TABLE OF SPECIFIC GRAVITIES, &c.-Continued. Cohesion in lbs. per square inch. Weight per cubic foot. 88:37 118.93 151.70 Cubic feet per ton. 126.60 14.76 133.63 16.76 17.69 137.68 16.20 133.75 16.75 139.12 16.10 2.040 127.50 17.56 Tension. Pressure. 6832 6170 Constant of Elasticity. Const. of Transv. Strength. REMARKS. Light yellowish brown; South well Church, &c. Light brown; Doncaster Old Church; Mansion House; thick- est bed 3 feet 6 inches. Day and Martin's, Holborn ; cream colour; the central beds, which are the best, are 4 feet thick. - Light cream; York Minster; Selby Cathedral; Westminster Hall; may be obtained 4 feet thick. Whitish cream; very numerous ancient and modern buildings; this stone vegetates very rapidly; it is liable to stun under the tool; thickest bed 2 feet 6 inches. Light yellow brown; York Min- ster, Beverley Minster, Ripon Minster, &c.; largest blocks 8′ × 3′ × 30', 7d. at quarry. 281 Ո Oak, fast grown Do. slow grown Do. Do. Canada. Do. Dantzic Do. African. Oolitic Stones, from to Do. Ancaster Quarry, Lincolnshire Do. Barnack Mill, Nor- thamptonshire - Do. Bath Lodge Hill, Somerset. Do. Bath, Baynton, Somerset. Do. Drew's Drew's Quarry (Bath), Somerset Do. Cranmore, Wilts. Do. Haydor, Lincoln- shire 58.56 38.25 52.87 42.36 *969 60.56 36.98 .872 54.50 *756 47.25 47.40 *993 62.06 2.362 147.66 1·968 123.00 2.228 139.25 16.08 *937 •846 2.188 1.856 116.00 1.968 1.961 2.148 136.75 2.134 16.38 123.00 18.21 122.62 18.26 134.25 133.42 16.78 11000 14000 3800 33 25 193000, or 111 104000, or 60 109000, or 63 268000, or 155 148000, or 86 299500, 1560 1265 1180 1760 1450 2570 "The nearer the magnesian lime- stones approach to equivalent proportions of carbonate of lime, and carbonate of magnesia, the more crystalline, and the better they are in every respect." Hydraulic lime is prepared from the magnesian limestone. Loose fibred, porous oak is of inferior quality; choose close grained, heavy, and fine pored specimens: it is principally used where timber is submitted to compression, and is in these days more in use for ship build- ing than constructive purposes. Cream colour; fine grained and compact; Wollaston Hall, and Belvoir Castle; blocks of 3 and 5 tons in 18 in. thickness. Whitish brown; often coarsely laminated; Peterborough Cathe- dral, and Croyland Abbey, &c.; beds up to 18 in. thick. The price of Bath is given at 6d. and 7d. at quarry. Light brown; Wells Cathedral; beds 20 in. thick. Dark cream colour; Lincoln Cathedral; blocks 14′ × 3′ × 4′. NAME OF MATERIAL. Do. Ketton, Rutland- shire Do. Vern Street Quarry, Portland Do. Grove Quarry, Bowes, Portland Do. Waycroft Quarries, Portland Do. Goslings Quarry, Portland Specific Gravity. 2.053 2.153 2.361 2.168 2.028 TABLE OF SPECIFIC GRAVITIES, &c.-Continued. Cohesion in lbs. per square inch. Weight per cubic foot. 128.33 134.62 147.62 best 135.50 126.80 Roach. Cubic feet per ton. 17.45 Tension. Pressure. 4000 6000 Constant of Elasticity. Const. of Transv. Strength. REMARKS. A good lasting stone, much used in ancient and modern buildings; dark cream colour; the rag stone, 3 feet 6 in. thick. Whitish brown; may be obtained of any practicable size; this stone has been employed in various public buildings. An oolitic carbonate of lime, with numerous fragments of shells; whitish brown; may be had 9 feet thick; the lower bed is the best; St. Paul's Cathedral. Oolitic carbonate of lime, with fragments of shells whitish brown; depth of freestone 13 feet; Goldsmiths' Hall and Reform Club House. Any practicable size, and the same remarks as above. There are fifty-six quarries in the Island of Portland, and about 24,000 tons are annually consumed: the top best is generally the best stone, being fine grained, and free from defects; in the bottom beds the stone is ill cemented, and does not stand the weather; in the east cliff quarries the stone is harder than in the west cliff. Besides the buildings already mentioned, Somerset House, St. Martin's-in-the-Fields, and St. Margaret's Tower, Loth- bury, are built of Portland stone; Westminster Bridge, and, we believe, Blackfriars, are constructed of Portland stone; but it is not a lasting material for hydraulic works. The oolitic formation consists of three strata, three times repeated; the stone is mostly a carbonate of 282 ૧૭ Do. Taynton, Oxon. Peat, from to Pebble Pewter Pine, Pitch Pine, Red Sand, from to Sandstone, from to Do. Abercarne, Mon- mouthshire Do. Barbadoes, Mon- mouthshire Do. Binnie, Linlith- gowshire Do. Bolton Quarry, Yorkshire - 2.147 1.008 1.472 2.600 7.248 63.00 92.00 163.00 453.00 41.25 41.06 1·440 90.00 1.872 117.00 1.648 103.06 2.687 167.94 2.687 167.94 13.33 2.348 146.75 15.26 2.246 140'06 15.99 126.78 17.66 *660 *657 135.93 2.028 15.74 lime, with shelly fragments, cemented together by a cal- careous and often argillaceous cement; this bed rests upon one of argillaceous sand and sandstone, which reposes on a thick deposit of clay. Brown; thickest bed 7 feet; Blenheim, and interior of St. Paul's. 153000, or 88 1630 23000, or 133 1341 We have a great variety of sandstones composed of quartzose grains principally, united together in most in- stances by an argillo-silicious cement, with various pro- portions of mica; the less we find the latter ingredient, the sounder the stone; we may, perhaps, venture on dividing the sandstones into four divisions, remembering, however, that there are a multitude of varieties of each division:-I. A sandstone of a grey, or bluish grey, fine, compact, very hard and heavy; this stone is one of the best, as the Craig Leith, and Abercarne, Elland Edge, Kentish rag: II. A stone of a coarse grained nature, as much so in some instances as the coarsest granite, the grains of which are united by a ferruginous cement; this second division is also composed of stone, hard and heavy, and is often the terror of masons from the quantity of steel "licked off" from their tools; in mouldings, it disintegrates rapidly from frost and wet, but for strength it is one of the best building materials, where, however, fine moulding is not required, as it pocks very much under the tools; it is commonly called 283 NAME OF MATERIAL. Do. Bramley Fall, Yorkshire Do. Calverley, Tun- bridge Wells, Kent Do. Craig-Leith, near Edinburgh Do. Crawbank, Lin- lithgowshire Do. Duffield Bank, Derbyshire • Specific Gravity. 2.275 1.388 2·318 2.063 2.125 TABLE OF SPECIFIC GRAVITIES, &c.—Continued. Cohesion in lbs. per square inch. Weight per cubic foot. Cubic feet per ton. 142.20 15'75 118.06 19.82 145.90 15.35 129.00 17.44 132.86 16.90 Tension. Pressure. · 4000 Constant of Elasticity. Const. of Transv. Strength. REMARKS. by the workmen "bastard granite;" such as the "Bram- ley Fall," and "Heddon:" III. And next in value, as a constructive material, we have a stone of a greenish and greenish brown tint, pretty hard, moderately heavy, but by no means equal to the former divisions, the disinte- gration being here much more rapid than in the former divisions; it also generally contains much more mica: IV. Division; this latter division consists of a stone of red, purple, yellowish red, and bright brown colours, and this last is the worst of the sandstones;-(it will be understood that these remarks are general and not special.) In the first two divisions, the stones may be had of any practicable size, of 4 and 5 feet depths; in the III. and IV. divisions, the beds are generally much thinner; the III. division yields the Yorkshire flags and stones, which may be very advantageously used in the construction of small arches. Blocks up to 18 tons; much used in hydraulic works. Brownish; beds 3 feet thick. Fine grained whitish grey; from 6 to 10 feet thick. Light rusty brown; fine grained; blocks 10 × 6 × 5. Light brown; moderately fine. 284 ! 285 Do. Duke Quarries, Derbyshire. Do. Gatherley Moor, Yorkshire Do. Gatton, Surrey Do. Glamis, Forfar- shire Do. Heddon, North- umberlandshire. Do. Hollington, Staf- fordshire Do. Humbie, Linlith- gowshire Do. White Grey Do. Longannet, Perth- shire • Do. Munlochy, Ross- shire. Do. Park Spring, York- shire 2.312 2.172 135.80 1.646 2.545 2·093 2.128 144.50 15.50 2.243 2.172 16.49 103.00 21.74 161.10 13.90 130.85 17.11 133.00 16.84 140·20 15.97 135.80 16.49 2.107 131.70 17.00 2.569 160.56 13.95 2.416 151'06 14.82 Do. Pensher, Durham 2:418 134.30 16.67 Do. Pyotdykes, Forfar- shire 2.600 162.50 13.78 5000 1 Red, brown, and grey; rather coarse; Penitentiary, London; and partly in filling of Water- loo Bridge. Cream colour; moderately fine; one bed 12 feet thick. Greenish light brown; blocks from 35 feet to 60 feet cube; Hampton Court and Windsor Castle. - Purple grey; moderately fine; thickest bed 6 feet. Light brown; coarse; in beds of 4 feet and 12 feet. Light brown grey; moderately fine; 30 feet and 40 feet square; and 8 feet thick; in Stafford- shire and Derbyshire. - Light grey and light brown; 8 feet thickest bed; fine grained. Light reddish brown; fine grained; 5 feet for thickest bed. Red variegated; fine grained; beds 2 feet to 6 feet thick. Light rusty brown; fine grained; 24 feet thickest bed. Light brown; coarse; thickest bed 20 feet. Dark grey; fine grained; 3 feet to 4 feet thickest bed; Dundee Harbour. 286 NAME OF MATERIAL, Do. Ringoodie, Perth- shire Do., Scotgate, York- shire Do. Stancliff, Derby- shire સુ Teak Tile, from to Tin, cast. → hammered Specific Gravity. Do.. Stenton, Durham 2:280 Do. Whitby Company, Yorkshire Shingle Slate, Welsh Do. Westmoreland, from Water, sea rain Zinc 2.560 2.371 TABLE OF SPECIFIC GRAVITIES, &C.-Continued. 2.528 158.00 2.028 1.424 2.880 Weight per cubic foot. 160.00 to Do. Anglesea Do. Cornwall, light blue 2-512 Steel, from 7.840 to 7.776 *745 1.816 113.50 1.856 116.00 7.291 455-70 7.299 456'20 1.027 64.18 1.000 65.50 7.184 449.00 Cubic feet per ton. 14.00 14.24 148*20 15.11 142:50 15.71 126.80 17.66 89.00 180.00 12:44 2-771 178.00 12.94 2.79:5 174*50 2.876 179.75 157.00 490.00 486.00 46.56 48.11 Cohesion in lbs. per square inch. Tension. 16000 Pressure. 3500 1400 3500 Constant of Elasticity. 309000, or 178 Const. of Transv. Strength. 2460 REMARKS. Dark grey; fine grained; any practicable size. Light greenish grey; moderately fine; 34 feet thickest bed. Light rusty brown; moderately fine; large size blocks. Light rusty brown; fine grained; 2 feet to 8 feet thick. Light brown; moderately fine; large blocks. 1 cubic foot = 6 gallons, 1 pint. TABLE II. OF SETS AND DEFLECTIONS ON CAST-IRON GIRDERS FROM THE PASSAGE OF TRAINS. 1 SECTIONS OF GIRDERS. SECTION 1. 9 123 <---301- TABLE OF SETS AND DEFLECTIONS ON CAST-IRON GIRDERS. No. 1 на со 4 106 7 со сс 9 10 11 12 13 14 15 Bearing in feet and inches. 6,10 8,0 8,9 10,0 Breaking Weight in tons, ac- cording to Formula of E. Hodg- kinson, Esq. 43.2 34.8 33.7 29.5 Permanent Deflections when tested in inches. 10 tons in centre. 0.12 0.18 REMARKS. Deflections in inches under a train of 6 cargs. at 30 m. [per hour. K Do. 0.02 0.03 0.03 0.02 do. 0.01 0.05 0.05 0.04 0.04 Do., 4 luggage wagons. 0.06 0.09 Do., 4 carriages. 0.06 0.12 288 SECTION 4, SECTION 2. 12-. SECTION 3, -1, 6- -1'. 4-"-------- 5:1 of-a 6 -K H 8' 17 1″ L 3" X 8" 15 " 16 17 18 19 20 21 22 23 24 ૨૭ ૨૭ 2" 8" ]1玲 ​[X]; 4310 13z." 81" Centre. End. 25 26 27 28 29 3:0 31 32 33 8,0 15 19 37.5 45 34.5 0.15 0.15 0.12 0.16 20 tons in centre. 0.06 0.12 O ● Deflections under train of 4 cargs., at 30 m. per hour. 0.05 0.06 0.05 0.03 Luggage train, 16 miles per hour. 0.12 Cast flat. 0.12 5 carriages, 33 miles per hour. 0.09 0.67 4 do. 36 miles per hour. 0.09 0.12 0.12 0.09 289 SECTIONS OF GIRDERS. TABLE OF SETS AND DEFLECTIONS ON CAST-IRON GIRDERS.-Continued. No. 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 Bearing in feet and inches. 19,9 Breaking Weight in tons, ac- cording to Formula of E. Hodg- kinson, Esq. 33.2 Permanent deflections when tested in inches. • 4 carriages, 40 miles per hour. 0.18 0.18 0.15 0.18 0.15 0.15 0.22 0.13 4 5 REMARKS. do. 25 miles per hour. 0.12 0.12 0.15 0.12 30 miles per hour. 0.14 0.14 0.21 0.15· 0.15 0.12 0.12 0.21 do. 290 SECTION 5. 2.0 JO" IN 18" コイ ​54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 28,0 28,6 30 64.3 63-1 60 , : 30 tons in centre. 0.68 0.56 0.56 0.53 0.55 0.52 0.50 0.56 0:43 0.56 0-48 0.50 0.62 0.50 30 tons in centre. 0.59 0.56 0.59 0.68 30 tons in centre. 0.45 0.47 0.47 0.54 0.56 0.55 0.50 0.54 0.43 0.56 0.50 Cast on edge. Cast on edge. Cast on edge. 291 SECTIONS OF GIRDERS. SECTION 6. -1', 8- SECTION 7. -2′0. 5 8" -1 + t 7" Y. 8" 6 13/15 X₁. 1½" 10" -10 TABLE OF SETS AND DEFLECTIONS ON CAST-IRON GIRDERS.-Continued. n 1/ No. 83 84 85 86 87 88 89 90 Bearing in feet and inches. 20 20 Breaking Weight in tons, ac- cording to Formula of E. Hodg- kinson, Esq. 50 67.5 Permanent Deflections when tested in inches. 0.50 0.56 0.50 0.62 20 tons in centre. 0.18 0.18 20 tons in centre. 0.12 0.21 REMARKS. Cast on edge. Cast flat. Cast flat. 292 SECTION 8. SECTION 9. 3,0″. -->> -~-~~-~~-~- - - - - - 0 1 2 -- =1ry 84 7" 8" X " 3 ±× 4' 1克 ​X 14″ 10" 14 11+ " 27," 91 92 93 94 95 96 97 98 99 30 40 60 84.1 30 tons in centre. 0.94 0.94 0.75 1.00 40 tons in centre. 0.87 0.75 0.85 0.87 0.63 Cast flat. Cast flat. Another foundry. 293 294 SECTIONS OF GIRDERS. SECTION 10. SECTION 10a 2 2 }} 6" =-12 18″ Centre. 4" 164" End. TABLE OF SETS AND DEFLECTIONS ON CAST-IRON GIRDERS.-Continued. A 2′ 6. -----བ-----0%------ 1 No. 100 101 102 103 104 105 106 107 Bearing in feet and inches. 36 42 Breaking Weight in tons, ac- cording to Formula of E. Hodg- kinson, Esq. ←-- 62.5 53.5 - Permanent Deflections when tested in inches. 20 tons in centre. 0.68 0.63 30 tons in centre.] 1.43 1.75 20 tons in centre. 0.94 0.87 1.12 1.13 "/ FO From end to end 48 feet. REMARKS. 18 1 · " EXPERIMENTS BY GEORGE RENNIE, Esq. TABLE III. On the Transverse Strength of Wooden Beams resting on rollers, 3 ft. 9 in. apart. Species of Timber. English Oak. Ditto African Oak Ditto Ditto Ditto Yellow Dantzic Fir . • Ash Beech. Elm Yellow Fir White Deal 295 English Oak. Ditto Ditto African Oak Ditto Ditto Yellow Dantzic Fir. • Sectional Breaking Dimensions. Weight. 2″ × 2″ "" "" "" "" "" "" 1″ × 1″ "" "" "" ور "" در 1369 1456 1425 1447 1873 1968 999 160 168 193 202 224 224 118 On the Tensile Strength of various Timbers per square inch. lbs. 12,000 10,500 10,000 9,600 10,000 lbs. American Oak . 12,200 English Oak 12,000 to 10,500 12,000 Riga Oak African Oak, from 15,600 to 14,000 On the Tensile Strength of different Metals per quarter of an inch square. Force in tons Tensile force in lbs. per square inch 11662 90*** 1218) Swedish Iron, English Iron, 296 TABLE IV. Cast-Iron, horizontal Cast-Iron, vertical Cast Steel, tilted Blister Steel, reduced per hammer Shear Steel, Cast Copper Fine yellow Brass Cast Tin. Cast Lead ditto ditto ditto Brass-hard Gun metal (2 trials) Wrought Copper, reduced per hammer . 8391 . 8322 . 7977 . 4504 3492 . 2273 2112 1192 . 1123 296 114 59.94 59.44 52.50 32.17 24.94 16.23 15.08 8.06 8.00 1.60 0.81 On the Transverse Strength of Cast-Iron Beams, for the purpose of deter- mining the effect of Wrought-Iron, when mixed with Cold-blast Blaenarvon Cast-Iron in different proportions. Quality of iron, No. 1, Blaenarvon, unmixed with wrought-iron, 4 ft. 6 in. long between supports, and 1 in. square. Three bars experimented upon, the average weight of each being 16 lbs. 5 oz. Average deflection with 506 lbs. in scale, 1.76 in. Breaking weight . 511 lbs. * These were unusually strong specimens, but the average of subsequent experi- ments on various Irons does not give more than 6 tons per square inch. EXPERIMENTS BY GEORGE RENNIE. 297 Three bars of similar dimensions to the above, with 10 per cent. of wrought-iron, and weighing upon an average 16 lbs. 9 oz. each; Average deflection with 611 lbs., 1·50 in. Breaking weight 625 lbs. Three bars of similar dimensions to the above, mixed with 20 per cent. of wrought iron, and weighing upon an average 16 lbs. 10 oz. each : Average deflection with 628 lbs., 1·58 in. Breaking weight . 672 lbs. The results are, that 10 per cent. wrought-iron, with No. 1 Blae- narvon cast-iron, gives an additional strength of 224 per cent., and with 20 per cent. wrought-iron an additional strength of 31 per cent. Similar Experiments were made with bars of Blaenarvon Cast-Iron, mixed with 30, 40, and 50 per cent. of Wrought-Iron respectively. The results were- For 30 per cent. wrought-iron, an increase in the strength of the bar of For 40 per cent. wrought-iron, an increase of . For 50 ditto ditto . X 60 per cent. 33 261 "" >> From which it appears that 30 per cent. of wrought-iron, mixed with the Blaenarvon, gives the greatest strength. 298 On the Comparative Strength of similar bars of Blaenarvon Cold-blast Iron in different positions, 1 in. square. EXPERIMENTS BY GEORGE RENNIE. In the form of an arch, 4 ft. 6 in. No. 1. between the abutments; rise or versed 1 sine of chord or span, bore 15 No. 2. No. 3. A bar, similar in every respect, but the arch inverted, bore and was therefore 31 times weaker than the former arched beam. The same with versed sine of chord or span, bore for the mean of 2 experiments. from whence it appears that the bar in this last position was 3.6 times stronger than the straight bar, and 5 times stronger than the bar in the form of an inverted arch of rise. 15 No. 4. Same as above, but reversed. 416 1267lbs 357.lbs 1729. lbs 280.ls. EXPERIMENTS BY GEORGE RENNIE. 299 On the Transverse Strength of Bars of Blaenarvon Iron, of different Forms, Depths, and Thicknesses, but of equal Weight with Bars of 1 in, square, or of 16 lbs. to 17 lbs. each. Rectangular Bars. Depth. in. 2 3 4 Upper side of bar Parabolic. Side of cube in inches. 2 2 2 2 Distance between supports. ft. in. 4 6 4 6 4 6 p 4 6 4 6 1 1/1/0 2 4 6 4 6 Weight of Bars Manley Talacre in lbs. 16 1/1/0 16, 10 oz. 17 12 12 11 11 Upper side of bar Semi-Elliptical. Designation. Anglesea Granite Blackburn ditto . 2 ditto. ditto. Anglesea ditto (4 specimens) Tamur Ditto ditto. ditto (fine grained) Cornish Heytor (split): Ditto ditto (crushed) Dartmoor (10 specimens), sup- ported without fracture. Dartmoor (5 specimens) 3 .. Thickness in. 2 3 Specific Gravity. ~102 HOHIH 2.704 2.441 2.454 2.419 2.708 2.650 3.050 1105 The permanent deflection varies from to of the breaking weight. 1o8 On the crushing of Stones, 2 specimens of each. Crushing Weight in lbs. 2.626 2.626 14/037/00 2 1/01 -10 247 147 29637 19400 10900 18950 23632 23425 24125 30912 46144 Breaking Weight in lbs. 18480 37408 1121 1568 2352 953 1429 950 1450 Crushing Weight per cubic inch in lbs. 3692 2425 1362 2368 2954 2928 3015 3864 5768 4676 The force required to crush a cubic inch of Cast-Iron is 70 tons. 3 2 300 An account of Experiments made on the powers of Stones to resist pressure, previously to the construction of New London Bridge. No. of Experi- ment. Dimensions of cube. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 in. 1 /1/1/0 در "" "} >> "" "" >> "" "" "" "" ") "" "" "" "" "" رو "" "" EXPERIMENTS BY GEORGE RENNIE. Name of Granite. Craig Leith Freestone (white) Dundee do. (dull grey) Heytor Granite Aberdeen, fine grained (yellow and grey). do.. Do. Do. do. (time 4 hours) Do. do., inclining to blue Peterhead (coarse red) Do. Granite Do. Ditto Jersey Do. Do. 5 3 6 15 5 13 6 3 6 4 7 7 fine grained (reddish) 68 blue kind 7 8 do. duration of Experiment 50 hours (blue) Guernsey (2 specimens) Granite. Cornish, large grained (light grey) Heytor Granite (another specimen) Sienite. Do. (2 specimens) Aberdeen Granite (red) . Do. • Crushing Weight. do. do. full grained (red) do. tus. cwt. qrs. lbs. 4 2 3 19 5 3 0 24 6 9 0 24 6 11 10 7 10 7 6 12 11 2 613 13 7 7 3 8 12 7 3 8 17 0 24 2 12 2 1 3 10 2 23 3 12 0 24 2 12 3 22 3 12 3 3 7 3 7 0 24 0 24 3 24 2 24 3 24 3 12 Crushing Weight in lbs. 9287 11560 14448 11560 15188 12657 13870 13967 16560 14360 16644 14778 23280 14857 24864 14920 29904 16100 19320 16100 19920 Average duration of Experiments 10 hours. A cubic foot of Granite, allowing for every variation, is capable of sustaining a pressure of from 600 to 700 tons, a stress far beyond any- thing that can ensue in the boldest arch. The arches of New London Bridge only give a pressure from 80 to 90 tons per cubic foot. EXPERIMENTS BY GEORGE RENNIE. Weights and Dimensions of Arches of London Bridge. Land Arches . Second Arches Middle Arch . Superficial Area. 625 785 930 Solidity. 30.000 37.680 44.640 with mortar fresh laid . 26.44° 24° Tons Weight. Angles at which the dressed Voussoirs commenced sliding without mortar Ditto 2097.98 2634.99 3121.68 Angles at which various substances stand when dry- Sand 32° to 33° Coarse Gravel. 35° Fine ditto. . 44° Fine flour Wheat, Barley. Peas. 33° 301 33.30° 25.30° These experiments on the angles repose of voussoirs made by our distinguished bridge builder, are particularly valuable, and still more from the important work in which they were noted. Rondelet, Art de Batir, Vol. IV., p. 273, says, " It has been found from experiments, that hard stones laid dry commenced slipping at an angle of 30 degrees, and with mortar fresh laid at angles of 34 and 36 degrees; and with soft stones on mortar fresh laid 45 degrees, when the centre of gravity does not fall without the base." From 34 to 36 degrees is repeated by Tredgold in Professor Barlow's edition. 302 C EXPERIMENTS BY GEORGE RENNIE. ANGLES of EQUILIBRIUM at which various substances stand, as taken with a Clinometer. Lime dust, as it falls from a spout Wheat Flour do. Malt do. do. Saw Dust do. Dry Sand do. Ditto, less dry do. Wheat Corn, unground do. Malt do. do. do. Common Mould Peas Wet Thames Gravel Dry Quick Sand from River Thames Wet do. do. Coarse Gravel Heaps Common Gravel Large Flints Ditto, half the size Ditto, approaching to sand do. do. Degrees. 45 44 . 40 44 . 40 . 39.16 . 37 37 37 ..35 35 to 36 35 . 40 35 to 38 . 35 to 36 40 to 45 35 34 to 35 : n E 1.5 w Ir! 40 1202 I } 骨 ​: F 6.2 b 40 1:1 B 2/2 & to to 2 47/x B h 40 T'S f 3 1 I 1 1 6.2 C T + / 3 d... 15'. 0".. Fig.14. 40 ♡ : 1 I 1 J 1 ↓ 1 2.3. 6.2 I I Wir 1 : D 601 t 3 6.2 Dj HERE IS AN 32 5 Fig. 7. 2011/4 C 3/2 1 6.2 f 27 10 g F 6 I 1 20 1 1 Fig. 13. 2. 21/2 I до 4 69.5 15'. 0 Fig. 15. D Co 3 7 2 1 A H B B 0 E ','" === 1 2 61.0"... h G } 1 1 ! 1 T I F Fig. 10. 3 15'. 0"... Fig.16. b. a A' 4 | f Į B % B f A ་་་ F 0 1 f 1 I } 1 1 69.5 2 2 1 1 1. C E Published by Atchley & C° 106 Gt Russell Street, London. April 1857. 1 15 36 31 D 3. ނ 19.4 f 1 A 1 1 1 Fiġ. Ai / ' on 14 8. 6 69.5 15 Fig. 20. ]) H E EN ENDE B A Tiff Fig. 9. 1 36 lic P H B D : • Fig. 4. ·1 I A 1 1 ↓ + I 1 Bi B P A H Ꮯ . 1 1 1 ! 1 1 I 100 H750 6.2 Fig. 2. 1 DIAGRAMS TO BRIDGES & c T K P4 I 1 1 1 Ġ4 12 दे 6.7 05 1 + 1 J I ! I 1 + 1 1 1 1 1 G5 M રે lg' L 12 8:2 Fig. 1. 1 Fig. 6. 2.8 8 4 2.45 Fig. 3. B. -X N 0.6 2.0 M I R B CO D Lov S Ά 1.5 D 1 1 1 Published by Atchley & Co 106 Gt Russell Street, London. April. 1857. Fig. 5. 7 R 8 R 16 E A H N 80 J.R.Jobbins. FIG. 11. a A F P N P Ꮽ 30 7 11 m 12 D m C 12 Z 11 10 h 19 P I zz 7 1 } T MURAD TANG HINIRE CURR W GENE, BANG "l "I *** ** ¿g 200 1 "l [1 I I 1 } I } I R 1 1 f I ૐ volán mớ 8.11865) anger Que 1 { 1 I { 1 1 1 I } 1 1 1 1 ! 1 ? } thing amatrangé Sing ľ } •E ) ! J 1 1 1 I 1 I 1 1 } CETTE CU are t Vet, manage tankar ototr@ren hastea vibrant 1 ނ Ir by seva pran ' 1 TT FIG. 12. + a. + A 1 1 1 I 15.0" 17,0" Radius. FIG. 21. 1 I 1 I ¦ 1 1 1 15.0" ī I 1 I I B a AKSHA Axis of Rail FIG. 22. Ballast Middle I 1 } 1. I Axis of Rail !! 213 11, 6" A FIG. 17. 1011× 1,0x 2', 1,6" 1,0 9×∞ 6×6 ७ вхо 6x 6x6 Ox∞ 1x8 ахо FIG. 23. ∞X4 1 x 10 6x6 25 feet span. FIG. 23 A. ∞ X 6 12 X 6 1 ×∞ 30 feet span. FIG. 23 B: 10 15X8 40 feet span. } : A N' A Ik F 2 I 사 ​0 F L C 1 } 1 1 ¦ I 1 1 } I } Im 1 FIG. 18. I 1 1 1 H " 1 ! 1 1 K FIG. 19. C I 0 /// H pr 1 1 Į 1 1 } I 1 G 'N 3 C Th n D B K' E 2 1 22 1 1 B } 1 1 ! I } { 1 1 } 1 M // Angle Irons 4 × 37% X From 27/2 × 21/2* 1/4 Livets 6 pitch 7/4 Inch Stay Rib. о 11/4 Rivets 5 pitch 7/16 Rib plate Fig. 27. 2 Angle Irons 2/2 × 2/1/2 + 1/½ 5 Feet apart R 34 Rivets 6 pitch # "}] 2/2 × 2/2 × 1/2" angle Iron X .X Gross Girder 5 Ft apart 1/4 plate A X 3 × 3 × 1/8 angle Fron 5 Ft apart Rivets 6' pitch: covers for the Butt joints and 1. 6 wide 3 rows of 1 Rivets on each side of joint ל Scale 1 Inch - 1 Foot Angle Iron 3½ * 3½ x ½ and 8 Rivets with 5 pitch "Rivets 5 pitch Fig.24 3/4 Rivets and 6 pitch с D D Fig. 25. 3 Shears B Fig. 20. 2 Shears A Shear Published by Atchley & C° 106 Gt Russell Street, London. April 1857. Jk jobbing Published by Atchley & Co 106 Gt Russell Street, London. April 1857. Scale 6 Feet 1 Inch Scale 5 Feet 1 Inch. Xx x x x x x x x x - - xxx x A | } пла //// ( 1 MA -- per me a internet or restart. Whe * B = ་ ་ ་ ་ ་ ་ ་ ་ ་ ་ ་ ་ ་ ་ ་ 1 www.w Batter Batter 1½ inch per foot --- *** Counterforts 10..ft apart 3 Bricks thick. F ---- Brock to contre and Batter - 1 Batter 1 in Rubble Counterforts 9 ft apart 3 feet thick 28 30 1 in Bubble 1 in 5 6 "1 JIN 17 dely a LO I X X X X X X X XT12 1 1 I I STIN 4- Mila PERMANENT WAY, FORMATION, DRAINS, ETC. 303 CHAPTER X. PERMANENT WAY, FORMATION, DRAINS, BALLASTING, LEVELS OF RAILS. CONNECTED with the permanent way, the four subjects in the heading of this chapter, come into primary and most important consideration ; the railways now constructed vary, for the width of formation, from 28 to 31 feet generally; and in order to effect a perfect drainage of this formation, it is necessary that the centre of the line should be higher than the sides, and this increase of height varies from 3 to 6 inches; the heavy traffic occasioned by earthworks will render it very difficult to maintain this ridge, if the seat of the ballasting is at once formed to this height; and, as an efficient drainage is indispensable, it is better to leave a small depth of excess of excavation, and to make the formation to its proper levels, immediately before the ballast is laid; this subject will be found to deserve more serious attention than might at first sight be afforded to it, for if this "formation" be not constructed so as to effect thoroughly the passage of waters into the "sidings," or side drains, whatever trouble may be devoted to the maintenance of the permanent way, will be comparatively lost, as well as the expense attending it, and this latter very serious consideration will be exactly in the proportion of neglect with which the permanent way is first constructed; the Engineer should therefore give strict injunctions to his inspectors to attend carefully to this, and should direct his personal attention to it as much as possible. Sub-contractors, to whom the earthworks are entrusted, will be generally found perfectly indifferent on this subject, as when once the ballasting is laid there are no means of detecting slovenly work without taking it up again. Sidings, or side-drains, form the next subject of consideration. In a hard solid substance, or in rock, and more especially where great economy is at first to be of paramount importance, a good ditch may be 304 PERMANENT WAY, FORMATION, DRAINS, PA } cut, with slopes battering in the same ratio as the slopes of the cuttings, but where the stratification is of a softer nature, where the excavation is deep, if not in rock, or where the slopes are liable to deterioration, from atmospheric effects, from rains, soaks, springs, or from the numerous injuries to which they are constantly liable, it is necessary, in order to preserve a free and uninterrupted passage for the waters and debris which accumulate at the foot of the cutting, that side-drains of rough masonry or brickwork be constructed, and these of sufficient capacity, by depth and width, to answer the purpose intended. In passing through marshy soils this capacity will require to be increased, often considerably, and transverse covered drains leading from the higher to the lower side of the way, will also be requisite; as, compa- ratively speaking, the drains have but little strain to resist, they may be constructed at the least possible cost-rough unhewn stones are all that is required, and these not of large scantling; of course, we are not now alluding to drains which are constructed across the formation for carrying off surface water, accumulating in ditches, and penned up, which must be disposed of, often by carrying it over the line to a lower level; specimens of these will be found amongst the examples of drains and culverts; and Figs. 1, 2, 3, 4, and 5 represent various kinds of permanent ways. chess why ... FIG. 1. FIG. 2. ESNEKANA AUR 20/0 Awaltelli Sm 196 ་་༔ The formation having been levelled to the degree of convexity required, the next operation is the ballasting, which is to form the 20 BALLASTING, LEVELS OF RAILS. 305 foundation for the sleepers, and which must be of such a nature as to allow water to percolate with the greatest freedom, in order that this FIG. 3. Musby Ground Dry Filling. A FIG. 4. FIG. 5. Dry Filling Leat Peat foundation be kept perfectly dry, or not only the sleepers will decay, but they, and consequently the rails, will be in considerable state of motion at the passage of every train, from a portion of the ballast being reduced to a soft muddy state. The best ballasting consists of hard broken stone, but it is expensive; good dry gravel forms excellent ballasting, and where found in excavations, should, as much as possible, be 306 PERMANENT WAY, FORMATION, DRAINS, preserved for this purpose; sand, mixed with broken stone, is equally good. Where these cannot be obtained, we may be satisfied with good clean cinders, or slag, which also answer the purpose very effectively; where none of these can be obtained, we may use hard shale, well burnt, for the upper coating of ballast, though it is rather liable to cake, but much less, however, than burnt clay, which we have seen used for this purpose; even the last may be improved by an admixture of sand before burning. Whether broken stone or gravel be used, care should be taken that all stones larger than an egg be broken up, and more particularly for the following reason: should a large stone be placed under a sleeper, and have an uncertain bearing, or present an angle to the underside of a sleeper, it will act like a pivot for this latter to move upon, and at least injure considerably the stability of the rails at this point, if it does no more. The ballasting will require to be at least 12 inches deep; it should be well levelled and well packed, and any means that could be used to force it down to a more solid bed would be a great improvement, as it would tend to lessen the subsidence which ensues from the first few trains passing over the line; the traffic, however, which is necessary for completing the works, will tend greatly to effect this. On this first bed of ballasting the sleepers are laid; these are generally of larch fir; they should be sound, free from shakes or signs of decay, straight, and of good form, as also of the scantlings specified by the specification, which are generally 8' or 9' x 9" or 10″ × 5″; besides these, there are the sleepers for the "joint chairs," which should be 12″ wide and squared; these sleepers should be carefully examined and measured, as delivered by the Contractor, and all inferior ones rejected. A broad notch or bed is cut on the upper side of the sleeper for the seat of the chair; and, as one end of the sleeper will often be thicker than the other, in consequence of the timber being unsquared, this stouter end should, on curves, be placed under the outside rail; attention should be given, that the beds cut for the reception of the chair be of full size to afford a sufficient seat, and also that the bed be perfectly flat; on this seat the chairs are fitted, as soon as the sleepers have been approximatively placed in their places along the line, and the rails placed in the chairs; the plate layers then commence setting out BALLASTING, LEVELS OF RAIĻS. 307 the straight lines and curves with reference to the stumps and bed moulds set out or checked by the Engineer, to which subject we will return presently, and gradually, by means of boning and guaging, which is done by means of a standard, measuring exactly the difference between the rails, the rails are brought to their true position; this being done, holes are driven in the sleepers for the reception of the spikes on one side, at each end of every length of rail, and next on the other side, the greatest care being used to have the guage constantly applied, and the spikes are driven; a piece of felt is often introduced between the chair and the sleeper, but vulcanized india-rubber will be found very superior, the india-rubber occupying a space equal to the seat of the chair, and the spikes being driven through it; the elastic nature of this substance tending materially to soften the shock which the wheels meet with as they successively cross each sleeper, and diminishing the effect of the vertical motion which the spike must experience in a greater or less degree in the sleeper. The position of the sleeper, chair, and rail is then permanently fixed, by the operation of what is termed boxing up, which is fixing under each sleeper about an inch, more or less, of a finer description of ballasting, consisting of fine gravel or good sand; by these means the rail is fixed permanently and correctly, both as regards the horizontal direction or centre line, and the levels of the gradient. Ballasting should then be filled up to the upper side of the sleeper. The guage commonly used by plate layers is an iron rod, of the shape shown at Fig. 6; the distance between A and B, being the FIG. 6. AL measure from rail to rail, but it meets with so much rough usage, and is so often bent and straightened again, if the men will take so much FIG. 7. B trouble, that it cannot be depended upon. Fig. 7 shows one of a superior kind, which should be made of a piece of hard, well-seasoned 3 308 PERMANENT WAY, FORMATION, DRAINS, wood, and, if varnished, will be less affected by damp; at A, there is a spirit level, by which the transverse level of the rails may be ascer- tained; inspectors should be supplied with such a guage, and with it, check with care the work of the plate layers. We have alluded to the centre line having to be set out a second, and often a third and fourth time, in excavations and embankments, and unless the Engineer, where he has to do this work, takes proper precautions, he will find it an endless work, or the Contractor will most likely commit great errors. By referring to the chapters on earthwork and setting out, the reader will find some advice on this subject, and we will here add some further instructions, by following which the work will be found much lessened, enabling therefore the professional man to attend to other matters requiring his attention. Where the tangents or straight lines are of any length, marks are always set up out of the works, by which, of course, this straight line of centre can always be found; and, by knowing from the section at what distance on this line the curve was commenced, this point may at any time be found also, and the curve set out; but on curves of 50 or 60 chains, or where these are numerous, we have pursued the following plan, by which, at any time, we could find exactly the original site of centre stumps; Fig. 8 will assist the explanation. Let A B be the d À e. d FIG. 8. •g b •h B ¿ $1 : f. curve, with the stumps shown by black dots; the straight lines between these are of course chords; take any two of these stumps-say a b, produce the line out beyond the edge of the cutting, as at dc, where drive in a couple of stumps likely to remain; at right angles to this BALLASTING, LEVELS OF RAILS. 309 line, and in line with a, sight out e a f, and drive in permanent stumps at each of these also; do the same thing at gb h, and make a note on the section book for reference hereafter; now at any future time, by sighting out these lines with accuracy, we find the exact position of a and 6, by which we may set out the curve; we do this in one or two places, generally along a curve; by these means there is no difficulty either in re-setting out or checking; in the outset this may appear rather long and tedious, but where a cutting of 30 feet or 40 feet deep is being excavated, and the centres are to be found, it will afford a very ready way at any time to obtain them; this, and the simple method already shown, will prevent all difficulties and loss of time; care must be taken in setting out the permanent centres of an embankment, that we pass through the centres of bridges and culverts; stumps at every chain length must be carefully and firmly driven into the top of the embankment or bottom of the cutting; by these stumps the position of the rails is fixed, and therefore, the straightness of the line where straight, and where otherwise, and the regularity of curve, depend on the position of these stumps. The levels connected with the height of the permanent rails require the utmost nicety in the operation of levelling, for although, except in a few situations, it will be almost impossible, at first, to keep the rails at the given heights, the bed-moulds remain, if properly fixed, for two or three years afterwards, for the reference of the plate layers. If the per- manent way be properly constructed, and these levels accurately set out, there need not be at any time, after consolidation, any deviation from the correct height. In cuttings, the bed-moulds,* with very few exceptions, will remain at the heights to which they are driven at first, but not so in embankments, on account of the settlement of this latter construction; but even here we shall have the bridges, on which the height of rails may be fixed with the utmost accuracy. Having pro- vided sufficient bed-moulds, commence from a P.P., or B.M., of the correct height of which there can be no possible doubt, and level from this to the temporary rails, or any convenient object at a stump or chain's length, and ascertain the difference of level, and, therefore, * A bed-mould is a stake of about 2′ × 3" x 3". 310 PERMANENT WAY, FORMATION, DRAINS, the height of the second object levelled to with regard to datum, and consequently to formation, as the height we require above datum at this point will be obtained from the section; say, for instance, that the height of the P.P. is 302 46 above datum, and the difference of level between this height and that of the temporary rail or other object levelled to is 23.10 lower; then we shall have 279.36 for the height above datum at this point; now refer to your pocket section, and in doing so be careful of two things:-first, that you do not mistake one chain stump for another, which would occasion one great error, and secondly, do not mistake formation for rail height; to practical men these two last hints may appear puerile, but we do not profess to write for these; the young practitioner, on the contrary, from the extreme facility with which either of these errors may be committed, is very likely to fall into them. To continue, we have found the height 279.36, and we carefully ascertain that this is at 5 miles 7 chains, where the formation height is 277.06 by the pocket section; but formation is 2:00 below the level of rails at every stump; then 277-06 + 200 279'06, which latter is to be rail height at this point; but 279.36 — 279.06 = 30, therefore, 279.36 is 30 too high, because it is 30 further from datum than 279.06, which is the correct height, and, consequently, we must have the top of our bed-mould 30 lower than 279.36; we trust this is sufficiently plain. Now, let the staff be still at 279-36, read off, and see that you read the same height as before, say 4.20; since it is 30 too high, if we could read off 4.50, the levelling staff would then be standing on some object at the correct height of rail, for 4.50 — 4·20 - 4.2030 ·30 fall, and 279·36 — ·30 = 30 279.06, which is rail height; we have, therefore, nothing to do but to drive in a bed- mould, until the levelling staff being placed upon it, we read off 4·50, when we shall have rail height at 5 miles 7 chains. We must now continue driving in these bed-moulds at intervals, a certain number of chains apart, up or down the line. On a level we should have but to plant the level midway between the first bed-mould, and the chain stump where the second would have to be driven; read off the staff on the first bed-mould, say 4.50; then driving in a bed-mould at any point along the intended level, until we read off 4:50 again; we should have a = - BALLASTING, LEVELS OF RAILS. 311 · second bed-mould level with the first, since 4.50 4.50 0.00, or no difference of level. But say we are going down the line, and that our gradient is 1 in 150 or 44 per chain; as we are going down we shall have to drive our bed-moulds lower than the last by a height of 44 × the number of chains further on at which the next bed-mould is driven, that is for 1 chain 44 lower, for 2 chains 44 x 288 lower, 3 chains 44 × 3 = 1.32 lower, and so on; setting out the levels along a straight line, it will be sufficient, if the bed-moulds be driven at 4 or 5 chains apart; but on a curve they should not be farther apart thaản 2 or 3 chains' length, and it will be found more likely to keep the work of the plate layers correct, if these heights be driven on one side and the other of the line alternately; supposing that we are now setting out the levels on a straight line and falling gradient, and at 5 chains apart, we should first plant the level about half-way, the staff remaining on the bed-mould 279-06; now 44 x 52.20; then at 5 miles 12 chains, × rail height will be 2.20 lower than 279 06 or 276 86. Read off the staff, say 4.80, and then let it be taken down to the bed-mould at 5 miles 12 chains; since the rails at this stump should be 2.20 lower than at the former stump, we shall have to add this depth to the last reading of 4.80; and this + 2.20 7.00; and the bed-mould must be driven until we read off correctly this second reading; for B. S. 7·00 – F. S. 4·80 = 2.20 fall, and as above, 279.06 2.20 276.86 from datum. Let us now suppose we are going up the gradient, instead of adding 44 × 5, we should have to deduct it from the reading required on the bed-mould, at 5 chains higher up the line, since this would be ·44 × 5 = 2·20 farther from datum since it is a rise; then having again planted the level midway to obtain this rise, read off the staff on bed- mould 279.06, say 5·43, then 5·43 — 2·20 = 3·23, which is the reading we shall require at 5 miles 2 chains; and the bed-mould must be driven until we have this reading, when the staff is held upon it; for B. S. 5·43 - F. S. 3.23 2.20 rise gradient upon 5 chains, and 279.06 + 2·20 (since we are rising, and, therefore, getting further from datum)= 281.26. On a descending gradient, therefore, the difference of levels for a certain number of chains must be added to the back sight; and on a rising gradient this quantity must be deducted from the back sight; Gagging = 312 PERMANENT WAY, FORMATION, DRAINS, in the first case, therefore, it is always +, in the second always - If we have been minute in explaining this, it is because we have once or twice found it rather unintelligible at first to beginners, who are apt in setting out to confuse the datum line with that which corresponds to the axis of the telescope of the level. Having set out two bed-moulds, we proceed in the same way if we require a hundred, and we will, there- fore, only add the farther recommendation, of planting the instrument about halfway between all the stations; and this more particularly to avoid the error consequent upon any want of adjustment in the level, and further, the most indispensable condition, that having set out the last bed-mould required, we must produce the levels on to the nearest B.M. for a check on the work, or we can have no assurance of the accuracy of the levels. On checking up to the B.M., of course the last height obtained must be that recorded on the pocket section for the height of the B.M.; any difference found will be so much error. Proceeding, for instance, as before, suppose we have set out 65 chains of levels, then 44 × 65 2860, and if we are descending 279 06 – 28.60 250 46 at 5 miles 72 chains; and on levelling up to the B.M., which suppose 262.50 we must find a rise of 12.04 between the last bed-mould set out, and the B.M., because all the levels refer to "Datum" as well as to "formation height," and "rail height," and from the first of which the two latter are originally deduced. In conclusion on this subject, we will add that these bed-moulds should be driven so firmly into the ground that intentional violence will alone disturb them, and that they should be so placed as to be out of the way of horses' feet and waggon wheels. · = On account of the tendency which carriages have to pursue a straight course when moving along curves, it is necessary to raise the outer rail, in order to counteract this effort; in the following table will be found the minima quantities usually allowed for this; for a full consideration of the subject, we refer the reader to Wood's Treatise on Railroads, Chap. IV., § 15. BALLASTING, LEVELS OF RAILS. 313 Radius of Curve in Chains. 10 20 = 14 30 = 9/90 40 60 = $ 80 = 1 mile. "" "" "" "" د. Rise in Inches. 2.00 1.07 0.71 0.53 0.35 0.25 This difference of level between the two rails on curves is given by depressing the inner rail, and raising the outer rail one-half the quantity of difference required. Professor Barlow, in his Treatise on the Strength of Materials, speaking of the Manchester and Liverpool railway, says, "I am disposed to estimate that about one in six of the plain butt joints is as perfect as can well be desired, and that another one in six is as bad as bad workmanship and negligence can make it; the remaining two- thirds varying in character between these two extremes;" this remark, made some ten or twelve years ago, may, we believe, with perfect justice be applied to almost every railway constructed; by experiments then made, Professor Barlow found that the deflection of the rail on a bad joint was nearly 50 per cent. greater than on a good one; the writer of these pages has repeatedly noticed one rail to be one-quarter and nearly one-half inch higher than that at the end of it. What must be the concussion of a 20 ton locomotive going over such an obstruction at 30 or 40 miles an hour? Again, the joints are often nearly an inch wide, where they should not be one-eighth of this width, and the crushing of the rail at such a joint will be shown by the lamination after a year's wear. These immense defects result solely from "bad workmanship and negligence;" and the Engineer in charge of the construction of a railway should, by the utmost attention on his part, as well as on that of his inspector, discountenance such shameful practice. It will be found that plate-layers, when once trained to a better kind of workmanship, will get on as well with it as with bad, and the wear and tear of stock, as well as the much less liability to accident, will amply repay this trouble. The utmost width of joint Y 314 PERMANENT WAY, FORMATION, DRAINS, ETC. which should be allowed when the rails are laid in cold weather, is one- eighth, and in warm weather, one-sixteenth; this, of course, as closely as can be obtained in practice, for with our utmost care we cannot obtain perfection. Where the curves are sharp or numerous on a line of railway, a certain proportion of the lengths of rails should be made of an increased length to allow for the greater development of the curve at the outer rail. By referring back to the articles in this chapter, the reader will observe, that the perfection of the permanent way consists in the con- struction of the formation, and an efficient drainage of the same; the quality of the ballasting and the manner in which it is employed; the seating of the sleepers and chairs, and the fixing of the rails; the straightness of the line, or the regularity of the curve; the correctness of the levels; the fitting of the butting joints, and the transverse levels of the rails. It will be seen at once, and the more by greater consideration, that the soundness of the permanent way depends, as a whole, upon a number of minutiæ, and the expense of its maintenance, as well as its efficiency, will be exactly in proportion to the degree of attention given to each and all of these details being practically carried out. 315 One in 10 11 12 13 14 15 16 17 ∞ ∞ ∞ 18 przed przed 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 Rise per Chain in feet. 6.6 6. 5.5 TABLE V.-GRADIENTS. 5'0769 4.7144 4.4 4.1243 3.8823 3.6 3.4736 3.3 3.1427 3. 2.8687 2.7499 2.64 2.5384 2.4437 2.3562 2.2757 2.2 2.1290 2.0625 2. 1.9411 1.8854 1.8333 1.7837 1.7367 1.6923 1.65 1.6097 1.5714 1.5348 1.5 1.4666 1.4347 1·4042 1.375 1.3469 Rise per Furlong in feet. 66. 60' 55* 50.76 47.14 44. 41.24 38.82 36. 34.73 33. 31.42 30° 28.68 27.49 26.40 25.38 24.43 23.56 22.75 22. 21.29 20.62 20. 19.41 18.85 18.33 17.83 17.36 16.92 16.50 16.09 15.71 15.34 15. 14.66 14.34 14.04 13.75 13.46 Rise per in feet. 528' 480. 440° Mile 406.15 377.14 352' 330' 310.58 288.88 277.89 264* 251*42 240' 229.56 220* 211.20 203.07 195'55 188.57 182.06 176' 170.32 165* 160** 155.29 150 85 146.66 142.70 138.94 135.38 132' 128.78 125.71 122.79 120° 117.33 114.80 112.34 110. 107.75 One in 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 Y 2 316 One in 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 Rise TABLE OF GRADIENTS.-Continued. Chain per in feet. 1.32 1.2941 1.2692 1.2452 1.2222 1.22 1.1785 1.1578 1.1379 1.1186 1.1 1.0819 1.0645 1.0476 1.0312 1.0152 1. •9850 •9705 •9565 •9428 •9295 •9166 •9041 •8918 *88* ⚫8684 *8571 •8461 ⚫8354 •825 •8148 •8048 *7951 •7857 •7764 •7674 •7586 •75 7415 Rise per Furlong in feet. 13.20 12.94 12.69 12.45 12.22 12.2 11.78 11:57 11.37 11.18 11. 10.81 10.64 10.47 10.31 10.15 10° 9.85 9.70 9.56 9.42 9.29 9.16 9.04 8.91 8.80 8.68 8.57 8.46 8.35 8.25 8.14 8.04 7.95 7.85 7.76 7.67 7.58 77.5 7.41 Rise Mile per in feet. 105.60 103.52 101.53 99.62 97.77 96. 94.28 92.63 91.37 89.49 88. .86.55 85.16 83.80 82.50 81.23 80' 78.80 77.64 76.52 75.42 74.36 73.33 72.32 71.35 70.40 69.47 68.57 67.69 66.83 66. 65.18 64.39 63.61 62.85 62.11 61.39 60.69 60. 59.32 One in 50 51 52 53 54 55 56 57 58 59 60 61 62 63 · 64 65 66 67 68 69 70 71 72 73 74 75 76 777 78 79 80 81 82 83 84 85 86 87 88 89 317 One in 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119. 120 121 122 123 124 125 126 127 128 129 Rise per Chain in feet. TABLE OF GRADIENTS.-Continued. *7333 ⚫7252 7173 7096 ⚫7021 *6947 *6875 '6804 *6734 '6666 '66 *6534 *6470 *6411 *6346 •6285 •6226 6168 •6111 ·6055 • .6 *5945 *5892 •5840 *5789 *5739 :5689 *5641 *5593 *5546 *55 *5454 *5409 *5365 *5322 *528 *5238 *5197 5156 •5116 · Rise per Furlong in feet. 7.33 7.25 7.17 7.09 7.02 6.94 6.87 6.80 6.73 6.66 6.60 6.53 6.47 6.41 6.34 6.28 6.22 6.16 6.11 6.05 6° 5.94 5.89 5.84 5.78 5.73 5.68 5.64 5*59 5.51 5.50 5:45 5*40 5.36 5.32 5.28 5.23 5.19 5.15 5.11 Rise per Mile in feet. 58.66 58.02 57.38 56.77 56.16 55.57 55* 54.43 53.87 53.33 52.80 52.27 51.72 51.26 50.77 50.28 49.81 49.34 48.88 48.44 48° 47.56 47.14 46.72 46.31 45.91 45.51 45.12 44.74 44.37 44° 43.63 43.27 42.92 42.58 42.25 41.92 41.57 41.24 40.92 One in 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 318 One in 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 Rise per Chain in feet. TABLE OF GRADIENTS.-Continued. *5077 *5038 *5 *4963 *4925 *4888 *4852 *4817 *4782 4748 *4714 *4680 *4647 *4615 *4583 •4552 *4520 *4489 *4459 *4429 •44 *4370 *4342 *4312 *4285 *4258 4231 •4204 4178 4152 • *4126 •4100 *4075 *4049 *4024 *4 *3975 *3952 *3928 ·3905 Rise per Furlong in feet. 5.07 5.03 5' 4'96 4.92 4.88 4.85 4.81 4.78 4.74 4.71 4.68 4.64 4.61 4.58 4.55 4.52 4.48 4.45 4.42 4.40 4.37 4.34 4.31 4.28 425 4.23 4.20 4.17 4.15 4.12 4.10 4.07 4.04 4.02 4* 3.97 3.95 3.92 3.90 Mile Rise per in feet. 40'60 40.29 40' 39.70 39'40 39.10 38.81 38.53 38.26 37.98 37.71 37.44 37.16 36.88 36.66 36.42 36.17 35.91 35.66 35.41 35.20 34.96 34.72 34.47 34.28 34.06 33.84 33.62 33.40 33.20 33° 32.79 32.58 32.38 32.18 32. 31.81 31.62 31.43 31.24 One in 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 319 One in 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 TABLE OF GRADIENTS.-Continued. Rise per chain in feet. *3882 *3859 *3836 *3813 *3793 *3770 *3748 *3726 *3705 *3687 *3666 *3646 *3626 *3606 *3586 *3568 *3548 *3529 *3510 *3491 *3473 *3455 *3437 *3419 *3402 *3385 *3368 *3351 •3333 '3316 *33 3284 *3267 *3251 *3235 •3219 *3203 *3187 •3172 •3157 Rise per Furlong in feet. 3.88 3.86 3.83 3.81 3.79 3.77 3.74 3.72 3.70 3.68 3.66 3.64 3.62 3.60 3.58 3.56 3.54 3.52 3.51 3.49 3.17 3.45 3.43 3.41 3.40 3.38 3.36 3.35 3.33 3.31 3.30 3.28 3.26 3.25 3.23 3.21 3.20 3.18 3.17 3.15 Rise Mile per in feet. 31.05 30.86 30.68 30.51 30:33 30:17 30' 29.83 29.66 29.49 29.33 29.17 29.01 28.85 28.69 28.53 28.37- 28.22 28.07 27.93 27.78 27.64 27.50 27.36 27.22 27.08 26.94 26.80 26.66 26.53 26.40 26.27 26.14 26.01 25.88 25.75 25.62 25.50 25.38 25.26 One in 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 320 One in 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 `214 245 246 247 248 249 Rise per Chain in feet. TABLE OF GRADIENTS.-Continued. •3142 *3127 3113 *3098 •3084 •3069 3055 •3040 •3026 •3013 • 3000 •2986 •2972 *2959 •2946 •2932 •2920 •2907 ·2894 •2882 •2869 2856 •2844 •2831 •2819 •2807 *2796 •2784 •2772 •2761 2750 •2738 •2727 2715 2704 *2693 •2682 *2673 2661 2650 Rise per Furlong in feet. 3.14 3.12 3.11 3.09 3.08 3.06 3.05 3.04 3.02 3.01 3. 2.98 2.97 2.95 2.94 2.93 2.92 2.90 2.89 2.88 2.86 2.85 2.84 2.83 2.81 2.80 2.79 2.78 2.77 2.76 2.75 2.73 2.72 2.71 2.70 2.69 2.68 2.67 2.66 2.65 Rise per Mile in feet. 25.14 25.02 24.90 24.78 24.66 24.55 24.43 24.32 24.21 24.10 24° 23.90 23.79 23.69 23.58 23.47 23.36 23.26 23.16 23.05 22.95 22.85 22.75 22.65 22.56 22.47 22.37 22.27 22.18 22.09 22. 21.90 21.88 21.77 21.66 21.55 21.46 21.37 21.28 21.20 One in 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 23£ 235 236 237 238 239 240 241 242 243 214 245 246 247 248 249 321 1 One in 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 TABLE OF GRADIENTS.-Continued. Rise per Chain in feet. *2640 *2629 •2618 *2609 *2598 2588 *2577 *2567 2559 •2548 2538 *2528 *2519 *2510 •2501 2492 2483 *2475 2466 2453 •2444 2435 *2426 *2417 *2408 *2399 •2390 •2381 *2372 *2363 *2357 2348 *2339 2331 *2323 *2315 *2307 •2299 *2291 2283 Rise per Furlong in feet. 2.64 2.62 2.61 2.60 2.59 2.58 2.57 2.56 2.55 2.54 2.53 2.52 2.519 2.510 2.50 2.49 2.48 2:47 2.46 2.45 2.44 2.43 2.42 2.41 2:40 2.399 2.390 2.381 2.37 2.36 2.35 2.34 2.339 2.331 2.32 2.31 2:30 2.299 2.291 2.28 Rise per Mile in feet. 21.12 21.04 20.96 20.87 20.79 20.71 20.63 20.54 20.45 20.38 20.30 20.23 20.15 20.07 19.99 19'92 19.84 19.77 19.70 19.63 19'55 19.48 19.41 19.34 19.27 19°20 19.13 19.06 18.99 18.92 18'85 18.78 18.72 18.66 18.59 18.53 18.44 18.38 18.32 18.26 One in 250 251 252 253 254 255 256 257 258 259 260 261 262 263 261 265 266 267 268 269 270 271 272 273 271 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 322 } One in 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 TABLE OF GRADIENTS.-Continued. Rise per Chain in feet. *2275 •2268 '2260 •2252 •2244 **2237 *2229 •2222 *2214 *2207 •22 *2192 •2185 •2178 •2171 2164 •2157 •2150 •2143 •2136 •2129 *2123 2116 *2109 *2102 •2095 •2088 •2081 •2074 *2068 •2062 *2055 *2049 •2012 •2036 '2030 *2024 2018 *2012 •2006 •2 Rise per Furlong in feet. 2.27 2.268 2.260 2.25 2.24 2.23 2.229 2.222 2.21 2.207 2.2 2.19 2.18 2.178 2.171 2.16 2.157 2.15 2.14 2.13 2.129 2.12 2.11 2.109 2.10 2.09 2.088 2.08 2.07 2.068 2.06 2.05 2.049 2.04 2.036 2.03 2.04 2.018 2:01 2.006 2. Rise per Mile in feet. 18.20 18.14 18.08 18.02 17.96 17.90 17.84 17.78 17.72 17.66 17.60 17.54 17.48 17.42 17.36 17.30 17.24 17.19 17.13 17.08 17.03 16.97 16.92 16.87 16.81 16.76 16.71 16.66 16.61 16.56 16.50 16.45 16.39 16.34 16.28 16.22 16.18 16.13 16.09 16.04 16' One in 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 323 TABLE VI. EXPLANATION OF TABLES. [L THE following tables are not intended to be applied in the same way as Macneill's Tables; they are for the purpose of shortening the calcula- tions of areas of cross sections, taken at chain stumps. The two cross sections below will at once explain this. Draw a b parallel to c d, the formation, scale ef, gh, and at base 30, slopes 1 to 1; opposite the C A. 21.75 A. FIG. 1. FIG. 2. g|l5.75 depths we have the areas of A and A, leaving but the triangle and trapezium to measure by the usual means. The tables are calculated for Base 17, 20, 28, 30, and 31, and for slopes from 1 to 1 to 3 to 1. 324 Depths. 1.00 2.00 3:00 4.00 1 to 1. 4 17.25 35.00 53.25 72.00 9.00 ½ to 1. 17.50 36.00 13.00 13.25 13.50 13.75 55.50 76.00 BASE 17.-Sectional Areas in Feet. 3 4 to 1. 5.00 91.25 97.50 103.75 6.00 120.00 129.00 111·00 7.00 131.25 143.50 155.75 8.00 17.75 37.00 57.75 80.00 10.00 173.25 193.50 213.75 195.00 220.00 245.00 11.00 217.25 247.50 277.75 1 to 1. 18.00 38.00 60.00 84.00 110.00 122.50 138.00 156.00 168.00 192.50 152.00 168.00 184.00 200.00 232.00 1 to 1. 18.50 40.00 64.50 94.00 263.25 305.50 347.75 390.00 400.81 411·74 422.81 14.00 14-25 269.10 312.96 356.92 275.06 320.62 366-18 280.91 328.28 375.55 287.00 336.00 385.00 434.00 293.01 343.78 394.55 445.31 14.50 239.06 351.62 404.19 456.75 14.75 305.03 359.48 413.85 467.21 15.00 311.25 367.50 427.75 480.00 15.25 317.38 375.51 433.67 491.81 15.50 323.56 383.62 443.69 503-75 15.75 329.76 391.78 234.00 274.50 315.00 270.00 320.00 370.00 308.00 368.50 429.00 12.00 240.00 276.00 301·00 348.00 420.00 492.00 2 to 1. 19.00 42.00 532.00 546.84 561.88 576.94 69.00 100.00 135.00 174.00 217.00 264.00 474.50 559.00 488.59 576.37 502.86 593.98 517.34 611.87 630.00 648.37 667.00 685.87 2 to 1. 19.50 44.00 73.50 108.00 147.50 160.00 192.00 210.00 241.50 296.00 3 to 1. Depths. 20.00 46.00 78.00 116.00 643.50 664.08 685.10 706-40 355.50 396.00 420.00 470.00 489.90 550.00 564.00 636.00 266.00 328.00 592.50 705.00 608.09 724.37 623.88 744.00 864.12 453.80 515.81 639.84 763.87 887.90 1.00 2.00 3:00 4.00 5.00 6.00 7:00 8.00 817.50 930.00 840.63 956.93 984.25 1011.93 9.00 10:00 11.00 12.00 728.00 13'00 751.93 13.25 776.22 13.50 800.93 13.75 788.00 826.00 14.00 749.90 851.43 14.25 772.12 877.25 14.50 793.60 903.13 14.75 15.00 15.25 15.50 15.75 325 Depths. 16.00 16.25 16.50 16.75 17'00 17.25 17.50 17.75 to 1. 4 to 1. 400.00 464.00 336.00 342.26 528.00 540.31 408.28 474.30 348.56 416.62 484.69 552.75 354.88 424.91 495.17 565.31 BASE 17.-Sectional Areas in Feet. 361.25 433.50 367.63 441.91 374.00 450.62 380.51 to 1. 1½ to 1. 656.00 784.00 672.34 804.37 688.88 825.00 705.59 845.87 505.75 578.00 722.50 516.39 590.77 739.53 527.19 459.27 538.05 603.75 756.88 616.81 774.34 468.00 549.00 470.78 560.04 485.62 571.19 494.50 582.37 1 to 1. 21.00 467.25 577.50 687.75 21.25 474·14 21.50 480.74 587.03 699.92 596.62 712-18 21.75 488-01 606.28 724.22 630.00 643.31 656.75 670.25 18.00 387.00 18.25 393.51 18.50 400.06 18.75 406.62 19.00 413.25 503.50 593.70 684.00 19.25 419.89 512.53 605.17 697.81 19.50 426.56 521.62 616.69 711.75 19.75 433.26 530.78 628.30 440.00 446.76 20.50 453.56 558.62 20.75 460.38 568.01 20.00 20.25 725.81 540.00 640.00 740.00 549.28 652.80 754.31 663.69 675.67 2 to 1. 2 to 1. 912.00 936.40 961.12 986.13 Depths. 1040·00 16.00 1068.43 16.25 1097.25 16.50 1126·43 16.75 3 to 1. 867.00 1011.50 1156.00 17.00 888.64 1037.40 1185.81 17.25 910.00 1062.12 1216.25 17.50 931-87 1089.39 1246.93 17.75 18.25 18.50 1197.50 1373.25 18.75 792.00 954.00 1116·00 1278.00 18.00 809.84 976.37 1142.90 1309.43 827.88 998.00 1170·12 1341.25 846.00 1021.75 864.50 1045.00 883·09 1068.37 901.88 1092·00 920.84 1115-87 1225.50 1406.00 1253.65 1438.93 1281 121471.25 1310·90 1505.93 19'00 19.25 19.50 19.75 20.00 940.00 1140·00 1340.00 1540.00 959.34 1164-37 1369.40 1574-43 20.25 768.75 978.88 1189.00 1398.12 1509.25 20.50 783.31 998.59 1213.87 1429.13 1644-43 20.75 798.00 1018.50 1239.00 1459.50 1680.00 812.81 1038.59 1264-37 1490·15 1715.93 827.75 1521.12 1752.25 21.50 842.81 1552·40 1788.93 21.75 21.00 21.25 1058.88 1290.00 1079.29 1315.87 326 Depths. 22.00 22.25 22.50 22.75 23.00 23.25 23.50 23.75 24.00 24.25 24.50 24.75 4 to 1. to 1. 495.00 616.00 502.00 625.78 509.00 635.62 516.14 645.53 523.25 655.50 530.37 665.50 537.56 675.62 544.76 685.78 BASE 17.-Sectional Areas in Feet. 2 to 1. 737·00 748.52 762.19 774.92 787.75 800.67 813.69 826.80 1 to 1. 552.00 696.00 559.26 706.28 566.56 716.62 866.69 573.89 727.03 879.92 1 to 1. 2 840.00 984.00 853.30 1000·31 1016-75 1033.31 2 to 1. 858.00 1100.00 1342.00 873.31 1120-79 1368.37 888.75 1141.88 1395.00 904.31 1163.09 1421.87 920.00 1184.50 1449.00 935.75 1206.09 1476.37 951.75 1227-88 1503.00 971.81 1249.84 1531.87 2 to 1. Depths. 1584.00 1826.00 22.00 1615.90 1863.43 22.25 1648.12 1901-25 22.50 1680.65 1939-43 22.75 1272.00 1560.00 1294·34 | 1588.37 1316.88 1339.00 3 to 1. 1713.50 1978.00 23.00 1746.62 2016.93 23.25 1780.12 2056.25 23.50 1813.90 2095.93 23.75 1848.00 2136.00 1882-40 2176.43 1617.00 1916.12 2217.25 1645.87 1951.95 2257.43 24.00 24-25 24.50 24.75 25.00 581.25 737.50 893.75 1050.00 1362.50 1675.00 1987 50 2300·00 25.00 25.25 588.64 748.03 907.42 1066.31 1385.50 1704-37 2023.05 2341.93 25.25 25.50 596.06 758.62 921.19 1083.75 1408.88 1734.00 2059.12 2383.25 25.50 25.75 603.31 769.28 934.80 1100.81 1431-79 1763.87 2095*40 2426.93 25.75 26.00 611.00 780.00 949.00 1118.00 1456.00 1794.00 2132.00 2470·00 26.00 26.25 618.51 790.78 963.04 1135.31 1479.84 1824.37 2168.90 2513.43 26.25 26.50 626.06 801.63 977.19 1152.75 1503.87 1855.00 2206-12 2557.25 26.50 26.75 633-44 812.53 991.42 1170-31 1528.09 1885.87 2243.65 2601·43 26.75 27'00 641.25 823.50 1005.75 1188.00 27.25 648.89 834.53 1019.67 1205 51 27.50 656.56 845.62 1034-68 1223.75 27.75 664.26 856.78 1049.29 1241.81 1552.50 1917.00 2281.50 2646.00 27.00 1577.09 1948.37 2319.65 2692.43 27.25 1601-87 1980.00 2358.12 2736.25 27.50 1626.84 2011.87 2396.90 2781.93 27.75 327 Depths. 28.00 28.25 28.50 28.75 to 1. to 1. 1 to 1. 3 to 1. Depths. 1652.00 868.00 1064.00 1264.00 879-28 1078.79 1278.31 1677-34 890.62 1093.68 1296.75 902-03 1108.67 1315.31 29.00 2044.00 2436·00 2828.00 28.00 2076.37 2475.40 2874-43 28.25 1702-87 2109.00 2515.12 2921.25 28.50 1728.59 2141.87 2555.15 2967.43 28.75 703.25 913.50 1123.75 1334.00 1754.50 2175.00 2595.50 3016·00 29.00 29.25 711·14 924.03 1138.92 1352.81 1780.59 2208.37 2636.15 3063·93 29.25 29.50 719.12 936.62 1156.43 1371.75 1806.87 2243.00 2687.12 3112.25 29.50 29.75 727.01 948.28 1169.54 1390.81 1833.34 2275.87 2718-40 3160.93 29.75 30.00 735.00 960.00 1185.00 1410.00 1860.00 2310.00 2760·00 3210·00 30.00 30.25 743.01 971.78 1200.55 1429.31 1886.84 2344-37 2801.90 3269-43 30.25 30.50 751·12 983.62 1216·19 1444.50 1913.87 2379.00 2843.12 3309.25 30.50 30.75 759.09 995.53 1231.79 1468.31 1940.84 2413.87 2885.40 3358.93 30.75 31.00 767.25 1007·50 1247·25 1488.00 1968.50 2449.00 2929.50 3410:00 31'00 31.25 775.39 1019.53 1263-67 1507.81 1996.09 2484.37 2972.65 3460·93 31.25 31.50 783.56 1031.62 1279:69 1527.75 2023.87 2520.00 3016.12 3512.25 31.50 31.75 791.76 1043-78 1295.80 1547.81 2051.84 2555.87 3059.90 3563.93 31.75 32.00 800.00 1056.00 1312.00 1568.00 2080.00 2592.00 3104.00 3616.00 32.00 32.25 808.26 1068.28 1328.30 1588.31 2108.34 2628.37 3148.40 3668.43 32.25 32.50 816.56 1080.62 1344-68 1608.75 2136.87 2665.00 3193.22 3721.25 32.50 32.75 824.89 1093.00 1360·00 1629.31 2165.09 2701·87 3238.15 3774-43 32.75 33.00 833.25 1105.50 1377.65 1650-00 33.25 841.64 1118.03 1394-42 1670.81 33.50 850.06 1130.62 1411·19 1691.75 33.75 858.51 1143.28 1428.04 1712.81 4 to 1. BASE 17.-Sectional Areas in Feet. 672.00 679.76 687.56 695.39 1 to 1. 2 to 1. 2 to 1. 2194.50 2739.00 3283.50 3828.00 33.00 2223.59 2776.37 3329.15 3881.93 33.25 2252.88 2814.00 3375.12 3936.25 33.50 2282.34 2851.87 3421·40 3990.93 33.75 328 Depths. 34.00 34.25 34.50 34.75 36.00 36.25 36.50 36.75 1½ to 1. 21 to 1. Depths. 4046.00 34.00 35.00 901.25 1207.50 1513.75 35.25 35.50 35.75 35.00 35.25 1863.75 1885.81 2493.87 3125.00 3150·62 4386.25 35.50 2524.84 3164.87 3196.15 4441·93 35.75 867.00 1156.00 1445.00 1734.00 2312.00 2890.00 2890.00 875.51 1168.78 1462-04 1755.31 2341.84 2928.37 2932.65 4101·43 34.25 883.06 1181.62 1479.18 1776-75 2371.87 2967.00 2975.62 4157.25 34.50 892.64 1194.53 1496.42 1798.31 2402.09 3005.87 3018.90 4213.43 34.75 1820.00 2432.50 3045.00 3062.50 4270.00 909.39 1220-53 1531·17 1841.81 2463.09 3084.37 3106.40 4326.93 918.56 1234.62 1548.68 926.76 1246·78 1566.29 936.00 1260.00 1584.00 1908.00 2556.00 3204.00 3240.00 4500.00 36.00 944.76 1273.28 1601·79 1930.31 2587.34 3244.37 3285.15 4558.43 36.25 953.56 1286.62 1619.68 1952.75 2618.87 3284.00 3330-62 4617.25 962.39 1300·03 1637.67 1975.31 2650.59 3325.87 3376.40 4676.43 37.00 971.25 1313.50 37.25 980.18 1327.07 37.50 37.75 36.50 36.75 37.00 1655.75 1998.00 2682.50 3367.00 3422.50 4736.00 1673.96 2020.81 2714·63 3408.37 3468.90 4795.93 37.25 989.06 1340.62 1692-18 2043.75 2746.87 3450.00 3515.62 4856.25 37.50 997.76 1353.78 1710.54 2066.81 2779.34 3491-87 3562.65 4916.93 37.75 1007·00 1368.00 1729.00 2090.00 2812.00 3534.00 3610.00 4978.00 38'00 1016.01 1381.78 1747.54 2113.31 2844.84 3576.37 3657.65 5039-43 38.25 1024.56 1395.62 1766.18 2136.75 2877.87 3619.00 3705.62 5101.25 38.50 1034:14 1409.53 1784.80 2160-31 2910.84 3661.87 3753.65 5162.93 38.75 4 to 1. BASE 17.-Sectional Areas in Feet. to 1. 4 to 1. 1 to 1. 2 to 1. 3 to 1. 38.00 38.25 38.50 38.75 39.00 1043.25 1423.50 1803.75 2184.00 2944.50 3705.00 3802.50 5226.00 39.25 1052.39 1437.53 1822-42 2207.81 2977.59 3748.37 3851·40 5288.93 39.50 1061.56 1451.62 1841.69 2231.75 3011.87 3792.00 3900.62 5352.25 39.50 39.75 1070-76 1465-78 1860-78 2255.81 3045.84 3835.87 3950.65 5415-03 39.75 39.00 39.25 329 Z BASE 17.-Sectional Areas in Feet. Depths. 4 to 1. to 1. 40.00 1080.00 1483.00 1880.00 2280.00 40.25 1089.26 1494.28 1889.30 2304.31 40.50 1098.56 1508.62 1918.68 2328.75 40.75 1107.89 1523.03 1938.17 2353.31 41'00 1117.25 1537.50 1957.75 2378.00 3218.50 4059.00 4202.50 5740·00 41.00 41.25 1126.64 1552.03 1977-42 2402-81 3253.59 4104-37 4253.90 5805.93 41.25 41.50 1135.06 1566.62 1997.18 2427.75 3288.87 4149.00 4305.62 5872.25 41.50 1145.51 1581.28 2016.80 2452.81 3324.34 4195.87 4357.15 5938.93 41.75 42.00 1155.00 1596.00 2037.00 2478.00 3360.00 4242.00 5124.00 6016-00 42.00 42.25 1164.56 1610.75 2057.04 2503.31 3395.74 4288.37 5180.90 6073-43 42.25 42.50 1174.06 1625.62 2077.18 2528.75 4335.00 5238.12 6141.25 42.50 42.75 1183.63 1640.52 2097.30 2554-30 5295.62 6209.40 42.75 41.75 3431·87 3468-07 4381.87 45.00 45.25 45.50 45.75 3 to 1. 4 1 to 1. 1 to 1. 2 to 1. 3 to 1. Depths. 3080.00 3880.00 4000.00 5480.00 40'00 3114.34 3924.37 4051.15 5544-43 40.25 3148.87 3968.00 4100.62 5609.25 40.50 3183.59 4013.87 4150*40 5674-43 40.75 43'00 1193.25 1655.62 2117.75 2580.00 3504 50 4429.00 5353.50 6278.00 43'00 43.25 1202.89 1670.53 2138.17 2605.81 3541.09 4476.37 5411.65 6346.93 43.25 43.50 1212.56 1685.62 2158.68 2631.75 3577.87 4524.00 5470.12 6416.25 43.50 43.75 1222.26 1700-78 2179.29 2657.81 3614-84 4571-87 5528.90 6485.93 43.75 44.00 1232.00 1716.00 2200.00 2684.00 3652.00 4620.00 5588.00 6556.00 44.00 44.25 1241.71 1731.28 2220.79 2710.31 3689.34 4668.37 5647.40 6626.43 44.25 44.50 1251.56 1746.62 2241.68 2736.75 3726.87 4717.00 5707.12 6697.25 44.50 44.75 1261.39 1762.03 2262.67 2763.31 3764-59 4765.87 5767.15 6768.43 44.75 2 to 1. 1271.25 1775.50 2283.75 1281·14 1743.03 2304.92 2816.81 1291.06 1808.62 2326.18 2843.75 1301.01 1824.28 2347.54 2870.81 2790.00 3802.50 4815.00 5827.50 6840.00 45.00 3840.59 4864-37 5888.15 6911.93 45.25 3878.87 5949.12 6983.25 45.50 3917 34 6010'40 45.75 4914.00 4963-87 • 4963-87 6010 7056.93 330 BASE 17.-Sectional Areas in Feet. Depths. to 1. to 1. 1½ to 1. 2 to 1. Depths. 6072.00 46'00 to 1. 46.00 1311·00 1840.00 2369.00 2898.00 3956.00 5014.00 7130.00 46.25 1321.01 1855.78 2390.54 2925.31 3994.84 5064.37 6133.90 7203-43 46.25 46.50 1331.06 1871-62 2412-18 2952.75 4033.87 5115·00 | 6195.12 7277.25 46.50 46.75 1341·14 1887.53 2433.92 2980.31 4073.09 5165.87 6268.65 7351.43 46.75 47'00 1351.25 1903.50 2455.75 3008:00 4112.50 5217.00 6321.50 7426.00 47.00 47.25 1361.39 1919.53 2477.67 3035.81 4152.09 5268.37 6384.65 7500.93 47.25 47.50 1371.56 1935.62 2499.68 3063.75 4191.87 5320.00 6448-12 7576-25 47.50 47.75 1381.78 1951.78 2521.79 3091.81 4231.84 5371.87 6511.90 7651.93 47.75 48'00 1392.00 1968.00 2544.00 3120.00 4272.00 5424.00 6576.00 7728.00 48'00 48.25 1402.26 1984.28 2566.29 3148.31 4312.34 5476.37 6640.40 7804-43 48.25 48.50 1412.56 2000.62 2588.68 3176.75 4352.87 48.50 1422.89 2017.03 2611.17 3205.31 48.75 5529.00 6705.12 7881.25 48.75 4393.59 5581.87 6770.15 7958.43 1 to 1. 2 to 1. 3 to 1. 49'00 1433.25 2033.50 2633.75 3234.00 4434.50 5635.00 6835.50 8036.00 49'00 49.25 1443.64 2054.33 2656.42 3262.81 4475.59 5688.37 6901.15 8113.93 49.25 49.50 1454.06 2066·62 2679.18 3291.75 4516.87 5742.00 6967.12 8192.25 49.50 49.75 1464.51 2083.28 2702.05 3320.81 4558.34 5795.87 7033-40 8270.93 49.75 50.00 1475.00 2100.00 2725.00 3350.00 4600.00 5850.00 7100·00 8350.00 50.00 50.25 1485.51 2116.78 2748.04 3379.31 4641.84 5904-37 7166.90 8429.43 50.25 50.50 1496.06 2133.62 2770.87 3408.75 4683.87 5959.00 7234.12 8509.25 50.50 50.75 1506.64 2150.53 2794-42 3438.31 4726.09 6013.87 7301-65 8589-43 50.75 51'00 1517.25 2167.50 2817.75 3468.00 4768.50 6069.00 7369.50 8670.00 51.00 51.25 1527.89 2184.53 2841.17 3497.81 4811:09 6124.37 7437.65 8750·93 51.25 51.50 1538.56 2201·62 2864.68 3527.75 4853.87 6179.00 7506.12 8832.25 51.50 51.75 1548.76 2218.78 2887.79 3557.81 4896.84 6235.87 7574.90 8913.93 51.75 331 Depths. 52.00 52.25 52.50 52.75 BASE 17.-Sectional Areas in Feet. 1 to 1. 4 3 to 1 4 1 to 1. to 1. 1½ to 1. 2 to 1. 1560.00 2236.00 7644.00 2912.00 3588.00 4940.00 6292.00 1570-76 2253.28 2935.79 3618.31 4983.34 6348.37 7713.40 1581.56 2270.62 2959.68 3648.75 7783.12 7853.15 1592.39 2288.03 2983.77 3689.31 J 2 to 1. 5026.87 6405.00 5070-59 6461·87 53'00 1603.25 2305.50 3007.75 3710·00 5114.50 6519.00 53.25 1614.14 2323.03 3031.92 3740-81 5158.59 6576.37 53.50 1625:06 2340.62 3056.18 3771-75 5202.87 6633.00 1636.01 2358.28 3080.54 3802·81 5247.34 6691.87 54.00 1647.00 2376.00 3105.00 3834.00 5292.00 6750·00 54.25 1658.01 2393.78 3129.54 54.50 1669.06 2411.62 3153.18 54.75 1680.64 2429.53 3179.42 3928.31 53.75 56.00 1736.00 2520.00 3304.00 4088.00 56.25 1747.26 2538.28 3329.29 4120-31 56.50 1758.56 2556.62 3354.68 4152.75 56.75 1769.89 2575.03 3380.17 4185.21 7044-37 55.00 1691.25 2447.50 3203.75 3960.00 5472.50 6985.00 55.25 1702:39 2465.53 3228-67 3991.81 5518.09 55.50 1713.56 2483.62 3253.68 4023.75 55.75 1724.76 2501.78 3278-79 4055.81 5563.87 7104.00 5609-84 7163.87 57'00 1780.25 2592.50 3405·75 | 4217·00 57.25 1791.64 2611.03 3430-42 4249.81 57.50 1803.06 2629.62 3456.18 4282.75 57.75 1814.51 2648.28 3482.04 4315.81 } 8208.00 3865.31 5336.84 6808.37 8279.90 3896.75 5381.87 6867.00 8352.12 5427.09 6925.87 8424.65 : 7893.50 7994.15 8065.12 8136.37 3 to 1. Depths. 8996.00 52.00 9078.43 52.25 9161.25 52.50 9244.43 52.75 · 9328.00 53.00 9411.93 53.25 9496.25 53.50 9580.93 53.75 9666.00 54.00 9751.43 54.25 9837.25 54.50 9923.43 54.75 8497.50 10010.00 55.00 8570 65 10096.93 55.25 8644-12 10184.25 55.50 8718.90 10271.93 55.75 5656.00 7224.00 8792.00 10360.00 56.00 5702-34 | 7284.37 8866.40 10448.43 56.25 5748.87 7345.00 8941-12 10537.25 56.50 5795.59 7405·87 9016 1510625.43 56.75 5841.50 7466·00 9090-50 10715.00 57'00 5888.59 7527.37 9166.15 10804.93 57.25 5935.87 7589.00 9242-12 10895.25 57.50 5983.34 7650.87 9318-40 10985·93 57.75 z 2 332 : Depths. 1.00 2.00 3.00 4.00 5'00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 1 to 1. 4 20.25 41.00 62.25 84.00 to 1. 20.50 42.00 64.50 88.00 13.00 344.50 302.25 13.25 308.85 352.71 13.50 315.56 361.12 13.75 322.26 369.53 14.00 329.00 14.25 335.76 14.50 342.66 14.75 349.28 BASE 20.-Sectional Areas in Feet. 4 378.00 386.53 395.12 403.73 to 1. 20.75 43.00 66.75 92.00 106.25 112.50 118.75 125.00 129.00 138.00 152.25 164.50 147.00 156.00 176.75 189.00 166.00 192.00 208.00 224.00 386.75 396.67 406.68 416.80 1 to 1. 342.00 200.25 220.50 240.75 261.00 301.50 225.00 250.00 275.00 300.00 350.00 400.00 250.25 280.50 310.75 341.00 401.50 462.00 276.00 312.00 343.00 384.00 456.00 528.00 427.00 437.30 447.69 458.10 21.00 44.00 69.00 96.00 468.75 15.00 356.25 412.50 15.25 363.13 421.26 479.42 15.50 370.06 15.75 377.01 430.12 490.10 439.03 501.05 1 to 1. 21.50 46.00 73.50 104.00 429.00 440.56 452.24 464.06 2 to 1. 2 to 1 22.00 22.50 48.00 50.00 78.00 82.50 112.00 137.50 150.00 174.00 192.00 213.50 238.00 256.00 288.00 513.50 528.34 543.36 558.59 3 to 1 Depths. 23.00 1.00 52.00 2.00 87.00 3.00 120.00 128.00 4.00 162.50 175.00 210.00 228.00 262.50 320.00 382.50 423.00 450.00 500.00 522.00 583.00 600.00 672.00 287.00 352.00 476.00 574.00 672.00 488.06 589.59 770.00 691.12 792.65 710.50 500.25 605.38 815.62 512.46 621.19 730.12 838.85 525.00 637.50 750.00 862.50 537.56 653.84 550.25 670.38 563.07 687.09 598.00 767.00 13.00 682.50 616.12 703.83 791.68 13.25 634.48 725.60 816.72 13.50 747.65 842.18 13.75 653.12 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 868.00 14.00 894.18 14.25 920.75 14.50 947.38 14.75 975.00 770.12 886.38 1002.68 790.50 811.12 15.00 15.25 15.50 910.62 1030.75 935.15 1059.18 15.75 333 Depths. 16.00 16.25 16.50 16.75 1 to 1. to 1. 384.00 448.00 512.00 391.01 457.03 523.05 396.06 466.12 534.19 405.13 475.26 545.42 18.00 18.25 18.50 18.75 2 to 1. 17.00 412.25 484.50 17.25 419.38 493.76 17.50 426.50 503.12 17.75 432.76 512.52 BASE 20.-Sectional Areas in Feet. 556.75 568.14 579.69 591.30 1 to 1. 576.00 589.06 602.25 615.56 629.00 642.52 656.25 670.06 14 to 1. 704.00 721.09 738.38 755.84 773.50 791.28 809.38 827.59 22 to 1. 3 to 1. Depths. 832.00 960.00 1088.00 16.00 985.15 1117·18 16.25 853.12 874.50 1010.62 1146.75 16.50 896.12 1036.38 1176.68 16.75 2 to 1. 918.00 1060.50 1207.00 17.00 940.39 1089.15 1237-56 17.25 962.50 1115.62 1268.75 17.50 985.12 1142.64 1300.18 17.75 441.00 522.00 603.00 684.00 448.26 531.53 614.79 698.06 455.56 541.12 462.87 550.75 846.00 1008.00 1170.00 1332.00 18.00 864.59 1031.12 1197.65 1364.18 18.25 626.69 712.25 883.38 1054.50 1225.62 1396.75 18.50 638.50 726.50 1078.00 1253.75 1429.50 18.75 19.00 470.25 560.50 650.70 19.25 477.64 570.28 662.92 19.50 485.06 580.12 19.75 492.56 590.03 20.00 500.00 600.00 700.00 20.25 507.51 610.03 712.55 20.50 515.06 620.12 725.19 522.63 630.26 737.92 21.00 530.25 640.50 750.75 21.25 537.89 650.78 763.67 21.50 545.24 661.12 776.68 21.75 553.10 671.53 789.27 908.06 1144-54 1381.12 902.25 741.00 921.00 1102.00 1282.50 1463.00 19.00 756.56 940.84 1126.12 1311.40 1496.68 19.25 675.19 770.25 960.38 1150.50 1340.62 1530.75 19.50 687.55 785.06 980.09 1175-12 1370.15 1565.18 19.75 800.00 1000.00 1200.00 1400.00 1600.00 20.00 815.06 1020.09 1225.12 1430.15 1635.18 20.25 830.25 1040.38 1250.50 1460.62 1670.75 20.50 845.56 1060.84 1276.12 1491.38 1706.68 20.75 861.00 1081.50 1302.00 1522.50 1743.00 21.00 876.56 1102.34 1328.12 1553.90 1779.68 21.25 892.25 1123.38 1354.50 1585.62 1816.75 21.50 1617.65 1854.18 21.75 20.75 334 Depths. to 1. 22.00 561.00 682.00 22.25 568.76 692.53 22.50 576.50 703.12 22.75 584.30 713.73 4 to 1. BASE 20.-Sectional Areas in Feet. 3 to 1. 4 803.00 815.27 829.69 843.17 1 to 1. 924.00 940.06 1166.00 1408.00 1187:54 1435.12 956.25 1219.38 1462.50 972.56 1231.34 1 to 1. 23.00 592.25 724.50 856.75 989.00 23.25 600.12 735.25 870.42 1005.56 23.50 608.00 746.12 884.19 1022.25 757.03 898.05 1039.06 23.75 615.89 24.00 624.00 768.00 24.25 632.01 779.03 24.50 640.06 790.12 24.75 648.14 801.28 25.00 656.25 812.50 25.25 664.39 823.78 25.50 672.56 835.12 25.75 680.76 846.53 26.00 689.00 858.00 26.25 697.27 869.53 26.50 705.56 881.13 26.75 713.89 892.78 27.00 722.25 904.50 27.25 730.64 916.28 27.50 739.06 928.12 27.75 747.51 940.03 1132.54 21 to 1. 3 to 1. 1892.00 1650.00 1682.65 1930.18 1715.62 1968.75 1490.12 1748.90 | 2007·68 1253.50 1518.00 1782.50 2047.00 1275.84 1546.12 1816.37 2086.68 1298.38 1574.50 1850.62 2126.75 1321.09 1603.12 1885.15 2167.18 2 to 1. Depths. 22.00 22.25 22.50 22.75 23.00 23.25 23.50 23.75 912.00 1056.00 1344.00 1632.00 1920.00 2208.00 24.00 926.03 1073.06 1367.09 1661.12 1955.15 2249.18 24.25 940-19 1090.25 1390.38 1690.50 1990.62 2290.75 24.50 954.17 1107.56 1413.34 1720.12 2026.20 2331.68 24.75 1437.50 1750.00 2062.50 2375.00 1461.34 1780.12 2098.80 2417·68 25.25 1160.25 1485.38 1810.50 2135.62 2460.75 25.50 1178.06 1509.09 1841.12 2172.65 2504.18 25.75 25.00 968.75 1125.00 983.17 1142.56 997.69 1012.05 26.00 26.25 1027.00 1196.00 1534.00 1872.00 2210.00 2548·00 1041.70 1214.06 1558.59 1903.12 2247.65 2592.18 1056.59 1232.25 1583.37 1934.50 2285.62 2636.75 26.50 1071.67 1250.56 1608.34 1966.12 2323.90 2681.68 26.75 1086.75 1269.00 1101.42 1287.56 1117.18 1306.25 1325.06 1633.50 1998.00 1998.00 2362.50 2727.00 27.00 1658.84 2030.12 2401·40 2774.18 27.25 1684.37 2062.50 2440.62 2818.75 27.50 1710-09 | 2095-12 2480.15 2865.18 27.75 į 335 BASE 20.-Sectional Areas in Feet. Depths. to 1. 1 to 1. 2 to 1. 3 to 1. Depths. 28'00 756.00 1148.00 1344.00 28.25 764.51 28.50 773.06 28.75 952.00 1736.00 2128.00 2520·00 2912.00 28.00 964.03 1163.54 1363.06 1762.09 2161.12 2560.15 2959.18 28.25 976.12 1179.18 1382.25 1788.37 2194.50 2600.62 3006.75 28.50 781.64 988.28 1194.92 1401.56 1814.84 2228.12 264140 3054.68 28.75 29'00 790.25 1000.50 1210.75 1421.00 1841.50 2262.00 2682.50 3103.00 29.00 29.25 798.89 1012.78 1226.67 1440.56 1868.34 2296.12 2723.90 3151.68 29.25 29.50 807.56 1025.12 1244.93 1460.25 1895.37 2330.50 2765.62 3200.75 29.50 29.75 816.26 1037.53 1258.79 1480.06 1922.59 2365.12 2807.65 3250.18 29.75 30'00 825.00 1050.00 1275.00 1500.00 1950.00 | 2400·00 2850.00 3300.00 30.00 30.25 833.76 1062.53 1291.30 1520.06 1977.59 2435.12 2892.65 3350.18 30.25 842.56 1075.12 1307.69 1540.25 2005.37 2470.50 2935.62 3400.75 851.39 1087.78 1324.04 1560.56 2033.09 2506.12 2978.65 3451.18 30.50 30.50 30.75 30.75 1 to 1. 2 4 to 1. 1 to 1. 33.00 932.25 1204.50 1476.75 33.25 941.39 1217.78 1494.17 33.50 950.56 1231.12 1511.69 33.75 959.76 1244.53 1529.29 2 to 1. 31.00 860.25 1100.50 31.25 869.14 31.50 878.06 31.75 887.01 32.00 896.00 1152.00 1408.00 1664.00 32.25 905.01 1165.03 1425.05 1685.06 32.50 914.06 1178.12 1442.18 1706.25 2234.37 2762.50 3290.62 3818.75 32.50 1340-25 | 1581.00 2061.50 2542.00 3022.50 3503.00 31.00 1113.28 1357.42 1601.56 2089.84 2578.12 3066.40 3554.68 31.25 1126.12 1374.19 1622.25 2118.37 2614.50 3110.62 3606.75 31.50 1139.03 1391.05 1643:06 2147.09 2651.12 3155.15 3669.18 31.75 2176.00 2688.00 3200.00 3712.00 32.00 2205.09 2725.12 3245.15 3765.18 32.25 32.75 923.14 1191.28 1459.17 1727.56 2263.34 2800.12 3336.40 3872.68 32.75 1749.00 2293.50 2838.00 3382.50 3927.00 33.00 1770.56 2323.34 2876.12 3428.90 3981.68 33.25 1792.25 2353.38 2914.50 3475.62 4036.75 33.50 1797.06 2383.59 2953.12 3522.65 4092.18 33.75 336 Depths. 34.00 34.25 34.50 34.75 4 35'00 35.25 35.50 35.75 to 1. to 1. BASE 20.-Sectional Areas in Feet. 3 to 1. 4 1 to 1. 969.00 1258.00 1547.00 1836.00 978-26 1271.53 1564.79 1858.06 987.56 1285.12 1582.68 1880.25 996.89 1298.78 1600.67 1902.56 1 to 1. 2 2414.00 2444.59 2475.37 2506.34 23 to 1. Depths. 2992.00 3570.00 4148.00 34.00 3031.12 3617.65 4204.18 34.25 3070.50 3665.62 4260.75 34.50 3713.90 4317.68 34.75 3110.12 2 to 1. 3 to 1. 3150.00 3150·00 3190.12 1006.25 1312.50 1618.75 1925.00 2537.50 1015.14 1326.28 1636.92 1947.56 2568.84 1025.06 1340.12 1645.18 1034.01 1354.03 35.75 1044.00 1368.00 3762.50 4375.00 35'00 3811.40 4432.68 35.25 1970.25 2600.37 3230.50 3860.62 4490.75 35.50 1673.54 1993.06 2632.09 3271.12 3910.15 4549.18 36'00 1692.00 2016.00 2664.00 3312.00 3960.00 4608.00 36'00 36.25 1053.51 1382.03 1710.54 2039.06 2696.09 3353.12 4010.50 4667.18 36.25 36.50 1063.06 1396.12 1729.18 2062.25 2728.37 3394.50 4060.62 4726.75 36.50 36.75 1072.64 1410.28 1747.92 2085.56 2760.84 3436.12 4111.40 4786.68 36.75 37'00 1082.25 1424.50 1766.75 2109.00 2793.50 3478.00 4162.50 4847.00 37.00 37.25 1091.89 1438.78 1785.67 2132.56 2826.34 3520.12 4213.90 4907.68 37.25 37.50 1101.56 1453.12 1804.68 2156.25 2859.37 3562.50 4265.62 4968.75 37.50 37.75 1111.01 1467.03 1823.79 2180.06 2892.59 3605.12 4317.65 5030.18 37.75 38.00 1121.00 1482.00 1843.00 2204.00 2926.00 3648.00 4370.00 5092.00 38'00 38.25 1130.76 1496.53 1862.29 2228.06 2959.59 3691.12 4422.65 5154.18 38.25 38.50 1140.06 1511.12 1881.68 2252.25 2993.37 3734.50 4475.62 5216.75 38.50 38.75 1150.39 1525.78 1901.05 2276.56 3027.09 3778.12 4529.00 5279.18 38.75 39.00 1160.25 1540·50 1920.75 2301.00 3061.50 3822.00 4582.50 5343.00 39.00 39.25 1170-14 1555.28 1940·17 2325.56 3095.34 3866.12 4636.40 5406.68 39.25 39.50 1180.06 1570.12 1960.19 2350.25 3130.37 3910.50 4690.62 5470.75 39.50 39.75 1190.01 1585.03 1980.03 2375.06 3165.09 3955.12 4745.15 5535.18 39.75 : 337 A A Depths. 40.00 40.25 40.50 40.75 to 1. 4 • 13 to 1. 21 to 1. Depths. 41'00 42.50 42.75 1200.25 1600.00 2000·00 2400.00 3200.00 4000.00 4800.00 5600.00 40.00 1215.01 1615.03 2020.05 2425.06 3235·09 4045.12 4855.15 5665.18 40.25 1220.06 1630.12 2040·18 2450.25 3270.37 4090·50 4910.62 5730.75 40.50 1230 14 1645:28 2050.42 2475.56 3305-84 4136·12 4966.40 5796.68 40.75 1240.25 1660.50 2080.75 2501.00 3341.50 4182.00 5022·50 5863.00 41.00 41.25 1250.39 1675-78 2101.17 2526.56 3377.34 4228.12 5078.90 5929.68 41.25 41.50 1260.56 1691.12 2121.68 2552.25 3413.37 4274.50 5135.62 5996.75 41.50 41.75 1270-76 1706.53 2142'05 2578.06 3449.59 4321.12 5192.65 6054.18 41.75 42.00 1281.00 1722.00 2163.00 2604·00 3486.00 4368.00 5250.00 6132.00 42.00 42.25 1291.26 1737.53 2183.79 2630:06 3522.59 4415.12 5307.65 6200.18 42.25 42.50 1301.56 1753.12 2204.68 2656.25 3559.37 4462·50 5365.62 6268.75 42.75 1311.88 1768-77 2225.65 2682.55 3596-32 | 4510·10 5423.87 6377.65 43.00 1322.25 1784.50 2246.75 2709.00 3633.50 4558.00 5482.50 6407.00 43.00 43.25 1332-64 1800-28 2267.92 2735.56 3670.84 4606.12 5541.40 6476.68 43.25 43.50 1343.06 1816.12 2289.18 2762.25 3708.37 4654.50 5600.62 6546.75 43.50 43.75 1353.51 1832.03 2310.54 2789.06 3746-09 4703.12 5660.15 6617.18 43.75 44.00 1364.00 1848.00 2332.00 2816.00 3784.00 4752.00 5720.00 6688.00 44.00 44.25 1374-61 1864-03 2353.54 2843.06 3822.09 4801.12 5780.15 6759.18 44.25 44.50 1385.06 1880.12 2375.18 2870.25 3860.37 4850.50 5840.62 6830.75 44.50 4.4.75 1395'64 1896.28 2396.92 2897.56 3898.84 4900·12 5901.40 6902-68 44.75 45.00 1406.25 1912.50 2418.75 2925.00 3937.50 4950·00 5962.50 6975.00 45'00 45.25 1416.89 1928.78 2440.67 2952.56 3976.34 5000·12 6023·90 7047.68 45.25 45.50 1427.56 1945.12 2462.68 2980.25 4015.37 5050.50 6085.62 7120.75 45.50 45.75 1438·20 1961-53 2484-79 3008-06 4054-59 5101-12 6147.65 7194.18 45.75 to 1. 2 BASE 20.-Sectional Areas in Feet. 3 2 to 1. 4 1 to 1. 2 to 1. 3 to 1. 338 Depths. 46.00 46.25 46.50 46.75 to 1. 4 49.00 49.25 49.50 49.75 BASE 20.-Sectional Areas in Feet. 50.00 50.25 50.50 50.75 1 to 1. 21 to 1. Depths. 3036.00 3064.06 4094.00 4133.59 5152.00 6210.56 7268.00 46.00 5203.12 6272.65 7342·18 46.25 3092.25 4173.37 5254.50 6335.62 7416.75 46.50 3120.56 4213.34 5306.12 6398:90 7491.68 46.75 to 1. 3 to 1. 1449.00 1978.00 2507·00 1459.75 1994.53 2529.29 1470.56 2011.12 2551.68 1481.39 2027-78 2574-17 47.00 1492.25 2044.50 2596.75 3149.00 4253.50 5358.00 6462.50 7567.00 47'00 47.25 1503.14 2061.28 2619-42 3177:56 4293.84 5410.12 6526.40 7642.68 47.25 47.50 1514.06 2078.12 2642.18 3206.25 4334-37 6590.62 7718.75 47.50 47.75 1525.01 2095'03 2665'04 3235.06 4375.09 6655.15 7795.18 47.75 5462.50 5515.12 1 to 1. 2 to 1. 3 to 1. 48'00 1536.00 2112.00 2688.00 3264.00 4416.00 5568.00 6720.00 7872.00 48.25 1547.01 2129.03 2711·04 3293.06 4457.09 5621.12 6785.15 7949.18 48.50 1558.06 2146.12 2734.18 3322.23 4498.37 5674-50 6850.62 8026.75 48.75 1569·14 2163.28 2757:42 3351.56 4539.84 5728.12 6916.45 8104.68 5782.00 6982.50 8183.00 7048.90 8261.68 49.00 49.25 1580.25 2180.50 2780.75 3381.00 4581.50 1591.39 2197.78 2804.17 3410.56 4623.34 5836.12 1602:56 2215.12 2827.68 3440.25 4665.37 5890.50 7115.62 8340.75 49.50 1613-76 2232.53 2851.29 3470.06 4707.59 5945.12 7182.65 8420.18 49.75 1625·00 2250.00 2875.00 3500.00 4750.00 6000.00 7250.00 8500.00 50.00 1636.26 2267.53 2898-79 3530.06 4792.59 6055.12 7317.65 8580·18 50.25 1647·56 2285.12 2922.68 3562.25 4835.37 6110.56 7385.62 8660.75 50.50 1658.89 2302.78 2946.67 3590.56 4878.34 6166.12 7453.90 8741-68 1670.25 2320.50 2970·00 3621.00 4921.50 6222.00 7522.50 8823.00 1681.64 2338.28 2994.92 3651.56 4964.84 6278-12 7591·40 8904.68 51.50 1693.06 2356.12 3019.18 3682.25 51.75 1704·51 2374.03 3043'04 50.75 51:00 51.00 51.25 51.25 5008.37 5052.09 6334.50 7660.62 8986.75 51.50 6391.12 7730.15 9069.18 51.75 3713.06 48'00 48.25 48.50 48.75 339 to 1. 1 to 1. 5096·00 6448.00 6505.12 1716·00 2392.00 3068.00 3744.00 1727.51 2410.03 3092.54 3775.06 5140.09 1739.06 2428.12 3117.18 3806-25 5184.37 6562.50 1750.64 2446.28 3141.92 3837.56 5228.84 6615.12 BASE 20.-Sectional Areas in Feet. to 1. 4. to 1. Depths. 52.00 52.25 52.50 8082.50 8153.90 52.75 53.00 1762-25 2464.50 3166.75 3869.00 5273.50 6678.00 53.25 1773.89 2482.78 3191.67 3900.56 5318.34 6736.12 53.50 1785.56 2501.12 3216.68 3932.25 5363.37 6794.50 8225.62 53.75 1797.26 2519.53 3241.79 3964.06 5408.59 6853.12 8297.65 54.00 1809.00 2538.00 3267.00 3996.00 5454.00 6912.00 54.25 1820.76 2556.53 3292.29 4028.06 5499.59 6971.12 54.50 1832.56 2575.12 3317.68 4062.25 5545.37 7030.50 54.75 1844.39 2593.78 3343.67 4092.56 5591.34 7090·12 55.00 1856.25 2612.50 3368.75 4125.00 5637.50 7150.00 55.25 1868.14 2631.28 3394.42 4157.56 5683.84 7210.12 55.50 1880.06 2650·12 3420.18 4190.25 5730.37 7270.50 55.75 1892.01 2669.03 3446.04 4223.06 5777·09 7331.12 1 to 1. 2 to 1. 56.00 1904.00 2688.00 3472.00 4256.00 5824.00 56.25 1916.01 2707.03 3498.04 4289.06 5871·09 56.50 1928.06 2726.12 3524-18 4322.25 5918.37 56.75 1940·14 2745*28 3550.42 4355.56 5965-84 57.00 1952.25 2764.50 3576.75 4389.00 6013.50 7638.00 57.25 1964-39 2783.78 3603.17 4422.56 6061.34 7700.12 57.50 1976.56 2803.12 3629.68 4456.25 6109.37 7762.50 57.75 1988.76 2822.53 3656.29 4490·06 6157·59 7825.12 7 7392.00 7453.12 7514-50 7576·12 2 to 1. 7800.00 7870.15 7940.62 8011·40 3 to 1 Depths. 9152.00 52'00 9235.18 52.25 9318.75 52.50 9402.68 52.75 9487.00 53.00 9571.68 53.25 9676.75 53.50 9742.18 53.75 8370.00 9828.00 54.00 8442.65 9914.18 54.25 8515 6210000·75 8588.90 10087·68 54.50 54.75 8662.50 10175.00 55.00 8736-4010262-68 55.25 8810.62 10350-75 55.50 8886-1510439·18 55.75 8960.00 10528.00 56'00 9035 15 10617·18 56.25 9110-62 10706.75 56.50 9186-4010795.68 56.75 9262-50 10887.00 57.00 9338.9010977-68 57.25 9415 62 11068-75 57.50 1160 9492-6511160·18 57.75 340 Depths. 1·00 2.00 3.00 4.00 5.00 6.00 7.00 8:00 1 to 1. 4 28.25 57.00 86.25 116.00 14.50 14.75 2 14.00 .441·00 14.25 449.76 458.56 . 467.28 to 1. 28.50 58.00 88.50 120.00 BASE 28.-Sectional Areas in Feet. 4 to 1. 15.00 476.25 532.50 15.25 485.13 543.26 15.50 494.06 554.12 15.75 503.01 565.03 28.75 59.00 90.75 124.00 146.25 152.50 158.75 165.00 177·00 186.00 195.00 204.00 208.25 220.50 232.75 245.00 240.00 256.00 272.00 1 to 1. 9.00 272.25 292.50 312.75 330.00 355.00 333.00 380.00 368.50 398.75 429.00 439.00 480.00 10.00 305.00 11.00 338.25 12.00 372.00 408.00 13.00 406.25 448.50 490'75 533.00 13.25 414.85 458.71 502.67 546.56 13.50 423.56 469.12 514.68 560.24 13.75 432.26 479.53 526.80 574-06 29.00 60.00 93.00 128.00 490'00 539.00 500.53 551.30 511·12 563.69 521.73 177.50 222.00 269.50 288.00 320.00 1 to 1. 29.50 62.00 97.50 136.00 588.00 686.00 602.06 703.59 616.25 721.38 576.10 630.46 739.19 2 to 1. 30.00 64.00 102.00 144.00 190.00 242.00 294.00 352.00 588.75 645.00 601.42 659.56 614.19 674-25 794.38 627.05 689.06 813.09 373.50 414.00 430.00 480.00 530.00 610.50 489.50 550.00 552.00 624.00 696.00 2 to 1. 30.50 66.00 106.50 152.00 627.50 702.00 786.50 634.34 722.12 809.83 651.36 742.48 833.60 668.59 763.12 857.65 757.50 870.00 775.84 892-12 202.50 215.00 258.00 276.00 318.50 343.00 374.00 416.00 914.50 937.12 784.00 882.00 805.12 826.00 848.12 3 to 1. Depths. 31.00 1.00 68.00 2.00 111.00 3.00 160.00 4.00 454.50 495.00 580.00 671.00 768.00 871.00 897.68 924.72 952.18 5'00 6.00 7.00 8:00 9.00 10.00 11.00 12.00 13.00 13.25 13.50 13.75 980.00 14.00 906.65 1008.18 14.25 931.62 1036.73 14.50 956.85 1065.38 14.75 1008.38 1034 62 1061·15 982.50 1095.00 15.00 1124.68 15.25 1154.75 15.50 1185.18 15.75 ½ to 1. 2 to 1. 576.00 512.00 640.00 521.01 587.03 653.05 530.06 598.12 666·19 539.13 609.26 679.42 1 to 1. BASE 28.-Sectional Areas in Feet. Depths. 16°00 16.25 16.50 16·75 17.00 548.25 620.50 692.75 17.25 557.38 631.76 706.14 719.69 575.76 654.52 733.30 17.50 566.50 643.12 17.75 18.00 585.00 18.25 594-26 18.50 603.56 18.75 612.87 700.75 666.00 747·00 677.53 760-79 689.12 774.69 788.62 19.00 622.25 712.50 19.25 631.64 724.28 19.50 641.06 736.12 19.75 650.51 748.03 20'00 660.00 760.00 20.25 669.51 772.03 679.06 20.50 784-12 688.63 796.26 21.00 698.25 808.50 21.25 707.89 820.78 21.50 717.24 833.12 21.75 727·10 20.75 1 to 1. 802.70 816.92 831.19 845.55 704.00 719.06 734.25 749.56 765.00 780.52 796.25 812.06 2 to 1. Depths. 16.00 832.00 960.00 1088.00 851·09 983.12 1115.15 870.381006·50 1142.62 1278.75 1216.00 1247·18 16.25 16.50 889.84 1030.12 1170.38 1310.68 16.75 828.00 909.50 1054.00 1198.50 929.28 1078.39 1227·15 949.38 1102.00 1255.62 969.59 1127.12 1284.64 990.00 1152.00 1314.00 1476·00 18.00 844.06 1010·59 1177.12 1343.65 1510.18 18.25 860.25 1031.38 1202.50 1373.62 1544.75 18.50 876.50 1052:25 1228.00 1403.75 1579.50 18.75 1254.00 1434.50 1615.00 19.00 1280·12 19.25 1465-40 1650.68 1116.38 1306.50 1496.62 1686-75 19.50 1138.09 1333.12 1528.15 19.75 1723.18 860.00 960.00 1160.00 1360.00 1560.00 1760.00 20'00 874.55 977.06 1182.09 1387.12 1592.15 1797.18 994.25 1204.38 1414.50 1624.62 1834-77 903.92 1011·56 1226.84 1442·12 1657.38 1872.68 918.75 1029.00 1249.50 1470·00 1690.50 1911.00 933.67 1046.56 1272.34 1498.12 1723.90 1949.68 948.68 1064.25 1295.38 1526.50 1757.62 1988.75 21.50 845.53 963.27 1082.06 1318.54 1555.12 1791.65 2028.18 21.75 20.25 889.19 21.00 21.25 893.00 909.56 926.25 943.06 1 to 1. 1073.50 1094 84 2 to 1. · 3 to 1. 1343.00 17.00 17.25 1375.56 1408.75 17.50 1442.18 17.75 20.50 20.75 341 342 BASE 28.-Sectional Areas in Feet. Depths. to 1. 1 to 1. 21 to 1. Depths. 22.00 737·00 22.25 1100.00 1342.00 1584.00 1826.00 2068.00 1118.06 1365.54 1613·12 1860.65 2108.18 1136.25 1389.38 1642.50 1154.56 1413.34 1672.12 22.50 895.78 1025·17 2357.18 • 24.00 24.25 858.00 979.00 22.00 746.76 870.53 993.27 22.25 756.50 S83.12 1009.69 1895.62 2148.75 22.50 22.75 766.39 1930.90 2189.68 22.75 23.00 776.25 908.50 1040-75 1173.00 1437.50 1437.50 1702:00 1966.50 2231.00 23.00 23.25 786·12 921.25 1056-42 1191.56 1461.84 1732-12 2002-37 2272.68 23.25 23.50 796.06 934.12 1063·19 1210.25 1486.38 1762.50 2038.62 2314.75 23.50 23.75 805.89 947.03 1088.05 1229.06 1511.09 1793.12 2075.15 23.75 24.00 816.00 960·00 1104.00 1248.00 1536.00 1824.00 2112.00 2400.00 24.25 826.01 973.03 1120.05 1267.06 1561.09 1855.12 2149.15 2443.18 24.50 836.06 986.12 1136.19 1286.25 1586.38 1886.50 2186.62 2486.75 24.50 24.75 846.14 999.28 1152.17 1305.56 1611·34 1918.12 2224.20 2529.68 24.75 25.00 856.25 1012·50 1168.75 1325.00 1637.50 1950.00 2262.50 2575.00 25.00 25.25 866.39 1025.78 1185.17 1344-56 1663·34 | 1982.12 2300·80 2619.68 25.25 25.50 876.56 1039-12 1201·69 1364.25 1689.38 2014.50 2339.62 2664-75 25.50 25.75 886.76 1052.53 1218.05 1384.06 1715.09 2047.12 2378.65 2710.18 25.75 26'00 897.00 1066.00 1235.00 1404.00 1742.00 2080.00 2418.00 2756·00 26.00 26.25 907.25 1079.53 1251.79 1424.06 1768.59 2113.12 2457.65 2802.18 26.25 26.50 917.56 1093·13 1268.69 1444.25 1795.37 2146.56 2497.62 2848.75 26.50 26.75 927.89 1106.78 1285.67 1464.56 27.00 938.25 1120.50 1302.75 27.25 948.64 1134.28 1319-42 27.50 959.06 1148.12 1337.18 27.75 969.51 1162.03 1354.54 1822.34 2180.12 2537.90 2895.68 26.75 1 to 1. 4 3 to 1. 1 to 1. 2 to 1. 3 to 1. 27.00 1485.00 1849.50 2214.00 2578.50 2943.00 1505.56 1876.84 2248·12 2619.40 2992.18 27.25 1526.25 1904.37 2282.50 2660.62 3038.75 27.50 1547.06 1932.09 2317.12 2702.15 3087·18 27.75 343 BASE 28.-Sectional Areas in Feet. Depths. 4 to 1. to 1. 1½ to 1. 28.00 980·00 1176.00 1960.00 2352.00 1372·00 1568.00 1389:54 1589.06 1988-09 2387.12 1407:18 1610.25 1424.92 2016.37 2044.84 30.25 30.50 30.75 2752.12 3224-65 3697·18 28.25 990:51 1190.03 28.50 1001.06 1204.12 28.75 1011.64 1218.28 1631.56 29.00 1022.25 1232.50 1442·75 | 1653·00 29.25 1032.89 1246.78 1460·67 1674.56 29.50 1043.56 1261.12 1480.93 1696.25 29.75 1054.26 1275:53 1496.79 1718.06 30.00 1065.00 1290.00 1515.00 1740·00 2190.00 2640.00 3090.00 3540:00 30'00 30.25 1075.76 1304-53 1533.30 1762.06 2219.59 2677.12 3134.65 3592.18 30.50 1086.50 1319.12 1551.69 1784.25 2249.37 2714.50 3179.62 3644.75 30.75 1097.39 1333.78 1570·04 1806.56 2279.09 31.00 1108.25 1348.50 1588.25 1829.00 2309.50 2790.00 3270.50 3751-00 31.00 31.25 1119·14 1363.28 1607.42 1851.56 2339.84 2828.12 3316.40 3804-68 31.25 31.50 1130.06 1378.12 1626.19 1874.25 2370.37 2866.50 3362.62 3858.75 31.50 31.75 1141.01 1393.03 1645.05 1897.06 2401.09 2905.12 3409.19 3913.18 31.75 32.00 1152.00 1408.00 1664.00 1916.00 2432.00 2944.00 3456:00 3968.00 32.00 32.25 1163.01 1423.03 1683.05 1943.06 2463-09 2983.12 3503.15 4023.18 32.25 32.50 1174.06 1438.12 1702-18 1966.25 2494.37 3022.50 3550.62 4078.75 32.50 32.75 1185.14 1453.28 1721-17 1989.56 2525.34 3062.12 3598.40 4134.68 32.75 33.00 1196.25 1468.50 1740-75 2013·00 2557.50 3102.00 3646·40 4191·00 33.00 33.25 1207.39 1483.78 1760·17 2036.56 2589.34 3142.12 3694.90 4247.68 33.25 1218.56 1499.12 1779.69 2060.25 2621.38 3182.50 3743-624304 75 33.50 1229.76 1514.53 1799.29 2084.06 2653.59 3223·12. 3792.65 4362.18 33.50 33.75 33.75 4 to 1. 1 to 1. 21 to 1. 2744.00 2786.15 2422.50 2828.62 2458.12 2 to 1. Depths. 3136.00 28.00 3185.18 28.25 3234.75 28.50 28.75 3 to 1. 2871-40 3284-68 29.00 2073.50 2494.00 2914.50 3335.00 2102-34 2530.12 2957.90 3385.68 29.25 2131.37 2566.50 3001.62 3436.75 29.50 2160.59 2603.12 3045.65 3488.18 29.75 344 Depths. to 1. 13 to 1. 34.00 1241.00 1530.00 1819.00 2108.00 2686.00 3264.00 34.25 1252.26 1545.53 1838.79 2132.06 2718.59 3305.12 34.50 1263.56 1561.12 1858.68 2156.25 2751.37 3346.50 34.75 1274.89 1576.78 1878.67 2180.56 2784.34 3388.12 35'00 1286.25 1592.00 1898.75 2205.00 2817.50 3430.00 4042.50 4655.00 35'00 35.25 1297.14 1608.28 1918.92 2229.56 2850.64 3472.12 4093.40 4714.68 35.25 35.50 1309.06 1624.12 1939.18 2254.25 2884.37 3514.50 4144.62 4774.75 35.50 35.75 1320.01 1640-03 1959.54 2279.06 2918.09 3557.12 4196.15 4835.18 36.00 1332.00 1656.00 1980.00 2304.00 2952.00 3600.00 4248.00 4896.00 36.25 1343.51 1672.03 2000.54 2329.06 2986'09 3643·12 4300.15 4957.18 36.50 1355.06 1688.12 2021.18 2354.25 3020.37 3686.50 4352.62 36.75 1366·64 1704.28 2041.92 2379.56 3054.84 3730.12 4405 40 35.75 36'00 36.25 5018.75 36.50 5080·68 36.75 BASE 28.-Sectional Areas in Fect. 1 to 1. 4 39.00 39.25 39.50 39.75 3 to 1 4 1 to 1. 2 to 1. 2 to 1. Depths. 3842.00 4420.00 34.00 3891.65 4478.18 34.25 4536.75 34.50 3941-62 3991.90 4595.68 34.75 3 to 1. 4458.50 5143.05 37.00 3818.12 4511.90 5205.68 37.25 3862.50 4565.62 5268.75 37.50 3907.12 4619.65 5332.18 37.75 37.00 1378.25 1720.50 2062.75 2405.00 3089.50 3774.00 37.25 1389.89 1736.78 2083.67 2430.56 3124.34 37.50 1401.56 1753.12 2104.68 2456.25 3159.37 37.75 1413.01 1769.03 2125.79 2482.06 3194.59 38.00 1425.00 1786.00 2147.00 2504.00 3230.00 3952.00 4674.00 5396.00 38'00 38.25 1436.76 1802.53 2168.29 2534.06 3265.59 3997.12 4728.65 5460.18 38.25 38.50 1448.06 1819.12 2189.68 2560.25 3301.37 4042.50 4783.62 5524.75 38.50 38.75 1460.39 1835.78 2211.05 2586.25 3337.09 4088.12 4839.40 5589.18 38.75 1472.25 1852.50 2232.75 2613.00 3373.50 4134.00 4894.50 5655.00 39.00 1484.14 1869.28 2254.17 2639.56 3409.34 4180.12 4950.40 5720.68 39.25 1496.06 1886.12 2276.19 2666.25 3446.37 4226.50 5006.62 5786.75 39.50 1508.01 1903.03 2298.03 2693.06 3483.09 4273.12 5063.15 5853.18 39.75 345 B B 1 to 1. 4 Depths. 2 to 1. 12 to 1. 40'00 1520.00 1920.00 2320.00 2720.00 3520.00 40.25 1532.01 1937.03 2342.05 2747.06 3557.09 40.50 1544.06 1954.12 2364.18 2774.25 40.75 1556.14 1971.28 2386.42 2801.56 3594.37 3631.84 £2 to 1. `BASE 28.-Sectional Areas in Feet. 1 to 1. ! 3669.50 3707.34 41.00 1568.25 1988.50 2408.75 2829.00 41.25 1580.39 2005.78 2431.17 2856.56 41.50 1592.56 2023.12 2453.68 2884.25 1604.76 2040.53 2476.05 2912.06 3783.59 3745.37 41.75 21 to 1. 3 to 1. Depths. 5920.00 40.00 40.25 5987.18 4320.00 5120.00 4367.12 5177.15 4414.50 5234.62 6054.75 40.50 4462.12 5292.40 6122.68 40.75 2 to 1. 4510.00 5350.50 6191.00 41'00 4558.12 5408.90 6259.68 41.25 4606.50 5467.62 6328.75 41.50 4655.12 5526.65 6398.18 41.75 42.00 42.25 42.50 1617.00 2058.00 2499.00 2940.00 3822.00 4704.00 5586.00 6468.00 42'00 1629.26 2075.53 2521.79 2968.06 3860.59 4753.12 5645.65 6538.18 42.25 1641.56 2093.12 2544.68 2996.25 3899.37 4802.50 5705.62 6608.75 42.75 1653·88 2110.77 2567.65 3024.56 3938.52 4852.10 5765.87 6679.65 42.50 42.75 43'00 1666.25 2128.50 2590.75 3053.00 3977.50 4902-00 5826.50 6751.00 43'00 43.25 1678.64 2146.28 2613.92 3081.56 4016.84 4952.12 5887.40 6822.68 43.25 43.50 1691.06 2164·12 2637.18 3110.25 4056.37 | 5002·50 5948.62 6894.75 43.50 43.75 1703.51 2182.03 2660.54 3139.06 4096.09 5053.12 6010.15 6967.18 43.75 44.00 1716.00 2200.00 2684.00 3168.00 4136.00 5104.00 6072.00 7040·00 44:00 44.25 1728.51 2218.03 2707.54 3197.06 4176.09 5155.12 6134.15 7113.18 44.25 44.50 1741.06 2236.12 2731·18 3226.25 4216.37 5206.50 6196.62 7186.75 44.50 44.75 1753.64 2254.28 2754.92 3255.56 4256.84 5258.12 6259.40 7260.68 44.75 45.00 1766.25 2272.50 2778.75 3285.00 4297.50 5310.00 6322.50 7335.00 45.00 45.25 1778.89 2290.78 2802.67 3314.56 4338.34 5362.12 6385.90 7409.68 45.25 45.50 1791.56 2309.12 2826.68 3344.25 4379.37 5414.50 6449.62 7484.75 45.50 45.75 1804.26 2327.53 2850.79 3374.06 4420.59 5467.12 6513.65 7560.18 45.75 1 to 1. 4. Depths. 12 to 1. 46.00 4462.00 5520.00 46.25 1817.00 2346.00 2875.00 3404.00 1829.76 2364.53 2899.29 3434.06 4503.59 5573.12 6642.65 46.50 1842.56 2383.12 2923.68 3464.25 4545.37 4587.34 46.75 1855.39 2401.78 2948.17 3494.56 BASE 28.-Sectional Areas in Feet. 1 to 1. 2 3 to 1. 4 1 to 1. 3525.00 4629.50 1881.14 2439.28 2997.42 3555.56 4671.84 1894.06 2458.12 3022.18 3586.25 1907.01 2477.03 3047-04 3617.06 4714.37 4757.09 2 to 1. 3 to 1. Depths. 6578.00 7636.00 46'00 7712.18 46.25 5626.50 6707.62 7788.75 46.50 5680.12 6772.90 7865.68 46.75 5734.00 6838.50 7943.00 47.00 5788.12 6904.40 8020.68 47.25 6970.62 8098.75 47.50 7037.15 8177.18 47.75 5842.50 5897.12 2 to 1. 47'00 1868.25 2420.50 2972.75 47.25 47.50 47.75 48'00 1920.00 2496.00 3072.00 3648·00 4800.00 5952.00 48.25 1933.01 2515.03 3097.04 3679.06 4843.09 6007.12 48.50 1946.06 2534.12 3122.18 3710.25 4886.37 6062.50 48.75 1959.14 2553.28 3147.42 3741.56 4929.84 6118.12 49'00 1972.25 2572.50 3172.75 3773.00 4973.50 6174.00 7374.50 8575.00 49'00 49.25 1985.39 2591.78 3198.17 3804.56 5017.34 6230.12 7442.90 8655.68 49.25 49.50 1998.56 2611.12 3223.68 3836.25 5061.37 6286.50 7511.62 8736.75 49.50 49.75 2011.76 2630.53 3249.29 3868.06 5105.59 6343.12 7580.65 8818.18 49.75 50.00 2025.00 2650.00 3275.00 3900.00 5150.00 6400.00 7650.00 8900.00 50.00 50.25 2038.26 2669.53 3300.79 3932.06 5194.59 6457.12 7719.65 8982.18 50.25 50.50 2051.56 2689.12 3326.68 3964.25 5239.37 6514.50 7789.62 9064.75 50.50 50.75 2064.89 2708.78 3352.67 3996.56 5284.34 6572.12 7859.90 9147.68 51'00 2078.25 2728.50 3378.75 4029.00 51.25 2091.64 2748.28 3404.92 4061.56 51.50 2105.06 2768.12 3431.18 4094.25 2118.51 2788.03 3457-04 4127-06 50.75 5329.50 6630.00 7930.50 9231.00 51.00 5374.84 6688.12 8001.40 9314.68 51.25 5420.37 6746.50 8072.62 9398.75 51.50 5466.09 6805.12 8144.15 9483.18 51.75 51.75 7104.00 8256.00 7171.15 8335.18 7238.62 8414.75 7306.40 8494.68 48'00 48.25 48.50 48.75 346 347 Depths. to 1. 1 to 1. 2 to 1. 5512.00 6864.00 8216.00 5558.09 6923.12 8288.15 6982.50 8360.62 7042.12 8433.40 52.00 2132.00 2808.00 3484.00 4160.00 52.25 2145.51 2828.03 3510.54 4193.06 52.50 2159.06 2848.12 3537.18 4226.25 5604.37 52.75 2172.64 2868.28 3563.92 4259.56 5650.84 53.00 2186.25 2888.50 3590.75 4293.00 5697.50 7102.00 8506.50 53.25 2199.89 2908.78 3617.67 4326.56 5744-34 7162.12 8579.90 9913.00 53'00 9997.68 53.25 53.50 2213.56 2929.12 3644.68 4360.25 5791.37 7222.50 8653.62 10084.75 53.50 53.75 2227.26 2949.53 3671.79 4394.06 5838.59 7283.12 8727.65 10162.18 53.75 54.00 2241.00 2970.00 3699.00 4428.00 5886.00 7344.00 54.25 2254.76 2990.53 3726.29 4462.06 5933.59 7405.12 54.50 2268.56 3011.12 3753.68 4496.25 5981.37 54.75 2282.39 3031.78 3781.67 4530.56 6029.34 7466.50 7528.12 2 to 1. BASE 28.-Sectional Areas in Feet. 4 to 1. 1 to 1. 2 to 1. 3 to 1. Depths. 9568.00 52.00 9653.18 52.25 9738.75 52.50 9824.68 52.75 8802.00 10260.00 54.00 8876.6510348·18 54.25 8951.62 10436.75 54.50 9026.90 10525.68 54.75 55.00 2296.25 3052.50 3808.75 4565.00 6077.50 7590.00 9102.50 10615.00 55.00 55.25 2310.14 3073·28 3836.42 4599.56 6125.84 7652.12 9178.40 10704.68 55.25 55.50 2324.06 3094.12 3864.18 4634.25 6174.37 7714.50 9254.62 10794.75 55.50 55.75 2338.01 3115.03 3892.04 4669.06 6223.09 7777.12 9332.15 10885.18 55.75 56.00 2352.00 3136.00 3920.00 4704.00 6272.00 7840.00 9408.00 10976.00 56.00 56.25 2366.01 3157.03 3948·04 4739.06 6321.09 7903.12 9485.1511067.18 56.25 56.50 2380.06 3178.12 3976.18 4774.25 6370.37 7966.50 56.50 56.75 2394.14 3199.28 4004·42 | 4809.56 6419.84 8030·12 9640.40 11249.68 56.75 57.00 2408.25 3220.50 4032.75 4835.00 6469.50 8094.00 57.25 2422.39 3241.78 4061.17 4880.56 6519.34 8158.12 57.50 2436.56 3263.12 4089.68 4916.25 6569.37 8222.50 57.75 2450.76 3284.53 4118.29 4952.06 6619.59 8287.12 9562-6211158.75 9718.50 11342.00 57'00 9796.90 11435.68 57.25 9875.6211528.75 57.50 11622∙18 9954-6511622.18 57.75 348 Depths. 1.00 2.00 3.00 4.00 1 to 1. 4. 9.00 30.25 61.00 92.25 124.00 5.00 6.00 7.00 222.25 8.00 256.00 1 to 1. 14:00 469.00 14.25 478.26 14.50 487.56 14.75 496.78 BASE 30.-Sectional Areas in Feet. 15.00 506.25 15.25 15.50 15.75 3 to 1. 30.50 62.00 94.00 128.00 132.00 30.75 63.00 99.75 562.50 515.63 573.76 585.12 525.06 534.51 596.53 1 to 1. 10.00 11.00 360.25 390.50 420.75 451.00 12.00 396.00 432.00 463.00 504.00 31.00 64.00 99.00 136.00 156.25 162.50 168.75 189.00 198.00 207.00 234.50 272.00 290.25 310.50 325.00 350.00 375.00 400.00 450.00 330.75 351:00 391.50 511.50 576.00 175.00 216.00 246.75 259.00 288.00 304.00 13.00 432.25 474.50 516.75 559.00 13.25 441.35 485.21 529.17 13.50 450.56 496.12 541.68 13.75 459.76 506.03 554.30 618.75 631.92 645.19 658.55 518.00 528.03 567.00 616.00 579.80 630.56 540.12 592.69 645.25 551.23 605.60 659.96 1 to 1. 2 31.50 66.00 103.50 144.00 2 to 1. 187.50 200.00 234.00 252.00 283.50 308.00 336.00 368.00 32.00 68.00 108.00 152.00 643.50 728.00 573.06 660.84 748.62 587.24 678.36 769.48 696.09 790.62 601.56 675.00 787.50 690.06 806.34 705.25 720.56 432.00 500.00 572.00 648.00 714.00 812.00 731.09 833.62 750.38 855.50 768.69 877.62 900.00 922.62 825.38 945.50 844.59 968.62 i 2 to 1. 32.50 70.00 112.50 160.00 212.50 270.00 332.50 400.00 3 to 1. 33.00 72.00 117.00 168.00 860.60 885.15 225.00 288.00 357.00 432.00 472.50 513.00 550.00 600.00 632.50 720.00 693.00 792.00 Depths. 1.00 2.00 3.00 4.00 5°00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 897.00 13.00 812.50 836.33 924.18 13.25 951.62 13.50 979.78 13.75 910.00 1008.00 14.00 935.15 1036.68 14.25 960.62 1065.75 14.50 986.35 1094.88 14.75 1012.50 1125.00 15.00 1038.88 1155.18 15.25 1065.62 1185.75 15.50 1092.65 1216.68 15.75 349 Depths. to 1. 16.00 544.00 608.00 16.25 553.51 619.53 16.50 563.06 631.12 16.75 572.63 642.76 4 to 1. 17.00 582.25 654.50 17.25 591.88 666.26 17.50 601.50 678.12 17.75 611.26 690.02 18.00 621.00 702.00 18.25 630.76 714.03 18.50 640.56 726.12 18.75 650.37 738.25 4 BASE 30.-Sectional Areas in Feet. to 1 1 to 1. 672.00 736.00 685.55 751.56 699.19 767.25 712.92 783.06 783.00 797.29 811.69 826.12 726.75 799.00 740.64 815.02 754.69 831.25 768.80 847.56 1 to 1. 2 to 1. Depths. 1248.00 16.00 864.00 992.00 1120.00 883.59 1015.62 2147.65 1279.68 16.25 903.38 1039.50 1175.62 1311.75 16.50 923.34 1063.62 1203.88 1344.18 16.75 2 to 1. 17.25 943.50 1088.00 1232.50 1377.00 17:00 963.78 1112.89 1261.65 1410.06 984.38 1137.50 1290.62 1443.75 17.50 1005.09 1162.62 1320.14 1477.68 17.75 864.00 1026.00 1188.00 1350.00 1512.00 18.00 880.56 1046.09 1213.62 1380.15 1546.68 18.25 897.25 1068.38 1239.38 1410.62 1581.75 914.00 1089.75 1265.50 1441.25 1617.00 18.50 18.75 3 to 1. 884.05 840.70 931.00 1111.50 1292.00 1472.50 1653.00 19.00 855.42 948.06 1133.34 1318.62 1503.90 1689.18 19.25 870.19 965.25 1155.38 1345.50 1535.62 1725.75 19.50 982.56 1177.59 1372.62 1567.65 1752.68 19.75 1000.00 1200.00 1400.00 1600.00 1800.00 20.00 914.05 1017.56 1222.59 1427.62 1632.65 1837.68 20.25 930.19 1035.25 1255.38 1455.50 1665.62 1875.75 20.50 945.42 1052.06 1268.34 1483.62 1698.88 1914.18 20.75 900.00 19.00 660.25 750.50 19.25 670.14 762.78 19.50 680.06 775.12 19.75 690.01 787.53 20'00 700.00 800.00 20.25 710.01 812.53 20.50 720.06 826.12 20.75 730.13 837.76 21.00 740.25 850.50 21.25 750.39 863.28 21.50 760.24 876.12 960.75 1071.00 1291.50 1512.00 1732.50 1953.00 21.00 976.17 1089.05 1314.84 1540.62 1766.40 1992.18 21.25 991.68 1107.25 1338.38 1569.50 1800.62 2031.75 21.50 21.75 770.60 888.03 1006.77 1125.56 1362.04 1598.62 1835.15 2071.68 21.75 → 350 1 Depths. 22.00 22.25 22.50 22.75 1 to 1. 2 to 1. 21 to 1. 781.00 791.26 902.00 914.03 1905.15 1940.62 1023.00 1144.00 1386.00 1628·00 1870.00 1037.77 1162.56 1410'04 1657.62 1054-69 1181.25 1434-38 1687.50 801.50 928-12 811.89 940.28 1070·67 1200'06 1458.84 1717.62 1976:40 822.25 954.50 1086.75 1219.00 1483.50 1748.00 2012.50 832.62 967.75 1102.92 1238.06 1508.34 1778.62 2048-87 843.00 981.12 1119.19 1257.25 1533.38 1809.50 2085.62 853.39 994.53 1135.55 1276.56 1558.59 1840-62 2277·00 23.00 2319.18 23.25 2361.75 23.50 2122.65 2404.68 23.75 24.00 864.00 1008.00 1152.00 1296·00 1584.00 1872.00 2160.00 2448.00 24.00 24.25 874.51 1021.53 1168.55 1315.56 1609.59 1903.62 2197.65 2491.68 24.25 24.50 885.06 1035·12 1185-19 1335.25 1635.38 1935.50 2235.62 2535.75 24.50 24.75 895.64 1048.78 1201·67 1355.06 1660.84 1967.62 2273.70 2580.18 24.75 25.00 906.25 1062.50 1218.75 1375.00 1687.50 2000.00 2312.50 2625.00 25.00 25.25 916.89 1076.28 1235.67 1395.06 1713.84 2032.12 2351.30 2670.18 25.25 25.50 927.56 1090.12 1252.69 1415.25 1740.38 2065.50 2390.62 2715.75 25.50 25.75 938.26 1104.03 1269.55 1435.56 1766.59 2098.62 2430.15 2761.68 25.75 26'00 949.00 1118.00 26.25 26.50 1287.00 1456.00 1794.00 2132.00 2470·00 2808.00 26.00 959.76 1132.03 1304.29 1476.56 1821.09 2165.62 2510.15 970.56 1146.13 1321.69 1497.25 1848.37 2199.50 2550.62 981.39 1160.28 1339·17 1518.06 1875.84 2233.62 2591.40 26.75 992.25 2854.68 26.25 2901.75 26.50 2949.18 26.75 1174.50 1356.75 1539.00 1903.50 2268.00 2632.50 2997.00 27.00 1188.78 1373.92 1560.06 1931.34 2302.62 2673.90 3046.68 27.25 1203.12 1392.18 1959.37 2337.50 2715.62 3093.75 27.50 1025.01 1217.53 1410.04 1987.59 2372-62 2757.65 3142.68 27.75 1003 14 1014.06 1581.25 1602.56 23.00 23.25 23.50 23.75 27.00 27.25 27.50 27.75 1 to 1. 4 BASE 30.-Sectional Areas in Feet, to 1. 4 to 1. 1 to 1. 3 to 1. Depths. 2112.00 22.00 2152.68 22.25 2193.75 22.50 2235.18 22.75 " 351 Depths. 1 to 1. 2 to 1. Depths. 28'00 1036·00 1232.00 28.25 1047.01 1246.53 1428.00 1624.00 2016·00 | 2408·00 2800.00 3192.00 28.00 1446.04 1645.56 2044.59 2443.62 2842.65 3241.68 28.25 28.50 1058.06 1261.12 1464-18 1667.25 2073.37 2479.50 2885.62 3291.75 28.50 28.75 1069.14 1275.28 1482-42 1688.56 2101.84 2515.62 2928.90 3341-68 28.75 29.00 1080.25 1290.50 1500.75 1711.00 2131.50 2552.00 2972.50 3393.00 29.00 29.25 1091.39 1305.28 1519·17 1733.06 2160.84 2588.62 3016:40 3444.18 29.25 29.50 1102.56 1320.12 1539.93 1755.25 2190.37 2655.50 3060.62 3495.75 29.50 29.75 1113-76 1345.03 1556.29 1777.56 2220.09 2662.62 3105.15 3547.68 29.75 30.00 1125.00 1350.00 1575.00 1800.00 2250·00 2700·00 3150.00 3600.00 30.00 30.25 1136.26 1365.03 1593.80 1822.56 2280·09 2737.62 3195.15 3652.68 30.25 30.50 1147.56 1380.12 1612.69 1845.25 2310.37 2775.50 3240.62 3705-75 1158.89 1395.28 1631.54 1868.06 2340·59 2813.62 3286.15 3758.68 30.75 1170-25 1410.50 1650.25 1891.00 2371·50 2371-50 2852.00 3332.50 3813.00 31.00 1181.64 1425.78 1914.06 2402.34 2890.62 3378.90 3867.18 31.25 1937·25 2433.37 2929.50 3425.62 3921.75 31.50 1960-56 2464-59 2968.62 3472.65 3976.68 31.75 30.50 30.75 1669.92 1193.06 1441·12 1204.51 1456.53 31.00 31.25 31.50 31.75 to 1. 1 2 BASE 30.-Sectional Areas in Feet. to 1. 3 to 1. 1689 19 1708.55 1 to 1. 2 to 1. 3 to 1. 32.00 1216·00 1472.00 1728.00 1984.00 2496.00 3008.00 3520.00 4032.00 32.00 32.25 1227.51 1487.53 1747.55 2007.56 2527.59 3047.62 3567.65 4087.68 32.25 32.50 1239.06 1503.12 1767.18 2031.25 2559.37 3087.50 3615.62 4143.75 32.50 32.75 1250·64 1518.78 1786-67 2055'06 2590.84 4199.18 32.75 3127.62 3663.90 33.00 1262.25 1534.50 1806.75 2079.00 2623.50 3168.00 33.25 1273.89 1550.28 1826.67 33.50 1285.56 1566·12 1846.69 33.75 1297.26 1582.03 1866.79 3712.50 4257.00 33.00 2103.06 2655.84 3208.62 3761.40 4314.18 33.25 2127·25 2688.38 3249.50 3810.62 4371·75 33.50 2151.56 2721·09 3290.62 3860.15 4429.68 33.75 352 Depths. to 1. to 1. 1 to 1. 3 to 1 Depths. 2754.00 3332.00 35.00 35.25 34.00 1309.00 1598.00 1887.00 2171.00 3910.00 4488.00 34.00 34.25 1320-76 1614.03 1907.29 2200.56 2787.09 3373.62 3960.15 4546.68 34.25 34.50 1332.56 1630.12 1927.68 2225.25 2820.37 3415.50 4010.62 4605.75 34.50 34.75 1344·39 1646.28 1948.17 2250.06 2853.84 3457.62 4061.40 4665'18 34.75 35'00 1356.25 1662.50 1968.75 2275.00 2887.50 3500.00 4112.50 4725.00 35.25 1367·64 1678.78 1989-42 2300.06 2921.34 3542.62 4163.90 4785.18 35.50 1380.06 1695.12 2010.18 2325.25 2955.37 3585.50 4215.62 4845.75 35.50 35.75 1391·51 1711-53 2031.04 2351.56 2989.59 3628.62 4267.65 4906.68 35.75 36'00 1404.00 1728.00 2052.00 2376.00 3024.00 3672.00 4320.00 4968.00 36.00 36.25 1416.01 174453 2073-04 2401.56 3058.59 3715.62 4372-65 5029.68 36.25 36.50 36.75 36.50 1428.06 1761.12 2094·18 2427.25 3093.37 3759.50 4425.62 5091.75 36.75 1440·14 1777-78 2115.42 2453.06 3128.34 3803.62 4478.90 5154.18 37.00 1452.25 1794.50 2136.75 2479.00 3163.50 3848.00 4532.50 5217.00 37.00 37.25 1464.39 1811.28 2158.17 2505.06 3198.84 3892.62 4586.40 5280.18 3.7.25 37.50 1476.56 1828.12 2179.68 2531.27 3234.37 3937.50 4640-62 5343.75 37.50 37.75 1488.51 1844-53 2201·29 2557.56 3270.09 3982.62 4695.15 5407.68 37.75 38.00 1501.00 1862.00 2223.00 2584.00 3306.00 4028.00 4750.00 5472.00 38.00 38.25 1513.26 1879.03 2244.79 2610.56 3342-09 4073.62 4805.15 5536.68 38.25 38.50 1525.06 1896.12 2266.68 2637.25 3378-37 4119.50 4860.62 5601.75 38.50 38.75 1537.89 1913.28 2288.55 2664.06 3414.59 4165.62 4916.50 5666.68 38.75 1550.25 1930.50 2310.75 2691.00 3451.50 4212.00 4972.50 5733.00 39.00 1562-64 1947.78 2332.67 2718.06 3487.84 4258.62 5038.90 5799-18 39.25 1575.06 1965.12 2355.19 2745.25 3525.37 4305.50 5085.62 5865-75 39.50 1587.51 1982.53 2377.53 2772.56 3562.59 4352.62 5142.65 5932.68 39.75 39.00 39.25 39.50 39.75 BASE 30.-Sectional Areas in Feet, 4 to 1. 1 to 1. 2 to 1. 2 to 1. C C Depths. 4 to 1. 1/2 to 1. 1½ to 1. 22 to 1. Depths. 40.50 40.25 6135.75 40.50 6204.18 40.75 40.75 41.00 40'00 1600.00 200.000 2400.00 2800.00 3600.00 4400.00 5200.00 6000.00 40*00 40.25 1612.51 2017.53 2422.55 2827.56 3637.59 4447.62 5257.15 6067.68 1625'06 2035.12 2445·18 2855.25 3675.37 4495.50 5315.62 1637-64 2052-78 2467.92 2883.06 3713:34 4543.62 5373.90 1650.25 2070.50 2490.75 2911·00 3751.50 4592.00 5432.50 41.25 1662.89 2088.28 2513.67 2939.06 3789.84 4640.62 5490-40 41.50 1675.56 2106.12 2536-68 2967.25 3828.37 4689.50 5550·62 41.75 1688.26 2124.03 2559.55 2995.56 3867-09 4738.62 5609.15 42.00 1701·00 2142.00 2583.00 3024.00 3906.00 4788.00 5670.00 6552.00 42.00 42.25 1713.76 2160.03 2606.29 3052.56 3945.09 4837.62 5730.15 6622.68 42.25 42.50 1726.56 2178.12 2629.68 3081.25 3984-37 4887.50 5790.62 6693.75 42.50 42.75 1739.38 2206.27 2653.15 3110.05 4023.82 4937.62 5851.37 6765.15 43.00 1752.25 2214-50 2676.75 3139.00 4063.50 4988.00 5912.50 6837·00 43.00 43.25 1765.14 2232.78 2700.42 3168.06 4103.34 5038.62 5973.90 6909.18 43.25 43.50 1778.06 2251.12 2724-18 3197.25 4143.37 5089.50 6035.62 6981.75 43.50 43.75 1791-01 2269.53 2748.04 3226.56 4183.59 5140.62 6097.65 7054-68 43.75 44.00 1804.00 2288.00 2772.00 3256.00 4224.00 44.25 1817-01 2306.53 2795.04 3285.56 1830.06 2325.12 1843 14 2343-78 42.75 4264-59 44.50 4305.37 2820.18 3315.25 2844-42 3345.06 44.75 1856.25 2362.50 2868.75 3375.00 1869.39 2381.28 2893.17 3405.06 4346 34 4387.50 4429.84 1882.56 2400.12 2917.68 3435.25 4470.37 1895.76 2419.03 294229 3465.56 4512.09 45.00 45.25 45.50 45.75 BASE 30.-Sectional Areas in Feet. · 0^3+ to 1. 1 to 1. 2 to 1. 3 to 1. 6273.00 41.00 6342-18 41.25 6411.75 41.50 6481.68 41.75 5192.00 6160.00 7128.00 44.00 5243.62 6222.65 7201.68 44.25 5295.50 6285.62 7275.75 44.50 5347.62 6348.90 7350·18 44.75 5400.00 6412.56 7425.00 45.00 5452.62 6476·40 7500·18 45.25 5505.50 6540-62 7575-75 45.50 5558.62 6605.15 7651.68 45.75 353 354 ¿ ½ t BASE 30.-Sectional Areas in Feet. to 1. Depths. 4 to 1. 1 to 1. 2 to 1. 2 to 1. Depths. 46°00 46.50 46.75 6048.00 7200.00 8352.00 48'00 6103.62 7267.65 8431.68 48.25 46.00 1909.00 2438.00 2967.00 3496.00 4554.00 5612.00 6670.00 7728.00 46.25 1922.26 2457.03 2991.79 3526.56 4596.09 5665.62 6735.15 7804.68 46.25 46.50 1935.56 2476.12 3016.68 3557.25 4638.37 5719.50 6800.62 7881.75 46.75 1948.89 2495.28 3041.67 3588.06 4680.84 5773-62 6860.40 7959.18 47'00 1962.25 2514.50 3066.75 3619.00 4723.50 47.25 1975.64 2533.78 3091.92 3650.06 4766.34 47.50 1989.06 2553.12 3117.18 3681.25 4809.37 47.75 2002.51 2572.53 3142.54 3712.56 4852.59 48.00 2016:00 2592.00 3168·00 3744.00 4896.00 48.25 2029.51 2611.53 3193.54 3775.56 4939.59 48.50 2043.06 2631.12 3219.18 3807.25 4983.37 6159.50 7335.62 8511.75 48.50 48.75 2056.64 2650-78 3244.92 3839.06 5027.34 6215.62 7403.90 8592.18 48.75 49.00 2070-25 2670.50 3270.75 3871.00 5071.50 6272.00 7472.50 8673.00 49.00 49.25 2083.89 2690.28 3296.67 3903.06 5115.84 6328.62 7541·40 8753.18 49.25 49.50 2097.56 2710.12 3322.68 3935.25 5160.37 6385.50 7610-62 8835.75 49.50 49.75 2111·26 2730.03 3348.79 3967-56 5205.09 6442.62 7680.15 8917.68 49.75 50.00 2125.00 2750.00 3375.00 4000.00 5250.00 6500.00 7750·00 9000.00 50.00 50.25 2138.76 2770.03 3401.29 4032.56 5295.09 6557.62 7820.15 9082.68 50.25 50.50 2152.56 2790.12 3427.68 4065.25 5340.37 6615.50 7890.62 9165.75 50.50 50.75 2166.39 2810.28 3454-17 4098.06 5385.84 6673.62 7961.40 9249.18 50.75 51.00 2180.25 2830.50 3480.75 4131.00 5431.50 6732.00 8032.50 9333.00 51.00 51.25 2194.14 2850-78 3507.42 4164.06 5477.34 6790.62 8103.90 9417.18 51.25 51.50 2208.06 2871·12 3534.18 4197.25 5523.37 6849.50 8175.62 9501.75 51.50 51.75 2222.01 2891.53 3560.54 4230.56 5569.59 6908.62 8247.65 9586.68 51.75 4 to 1. 1 to 1. 3 to 1. 5828.00 6932.50 8037.00 47.00 5882-62 6998'90 8115.18 47.25 5937.50 7065.62 8193.75 47.50 5992.62 7132.65 8272.68 47.75 355 Depths. 52.00 52.25 52.50 52.75 BASE 30.-Sectional Areas in Feet. 56.00 56.25 56.50 56.75 to 1. to 1. to 1. 2236.00 2912.00 3588.00 4264.00 2250.61 2932.53 3615.04 4297.56 2264-06 2953.12 2278.14 2973.78 1½ to 1. | 2 to 1. 5616.00 6968.00 5662.59 7027.62 3642.18 4331.25 5709.37 3669.42 4365'06 7087.50 7147.62 5756.34 1 to 1. 3696.75 4399.00 4433.06 3751.68 3751-68 4467.25 3779.29 4501.56 5803.50 7208.00 5850.84 7268.62 5898.37 7329.50 5946.09 7390.62 53.00 2292.25 2994.50 2306.39 3015.28 3724.17 5994.00 7452.00 53.25 53.50 2320.56 3036·12 53.75 2334·76 3057.03 54.00 2349.00 3078.00 3807.00 4536.00 54.25 2363.26 3099.03 3834-79 4570.56 6042.09 7513.62 54.50 2377.56 3120.12 3862.68 4605.25 6090.37 7575.50 54.75 2391.89 3141.28 3891.17 4640.06 6138.84 7637.62 55.00 2406.25 3162.50 3918.75 55.25 2420-64 3183.78 55.50 2435.06 3205.12 55.75 2449.51 3226.53 4675.00 6187.50 7700.00 3946.92 4710.06 6236.34 7762.62 3975.18 4745.25 6285.37 7825.50 4003 54 4780-56 6334.59 7888.62 4032.00 2478.51 3269.53 4060.54 2493.06 3291.12 4089.18 4887.25 2507.64 3312-78 4117.92 4923.06 2464.00 3248.00 4816.00 4851.56 6384.00 7952.00 6433.59 8015.62 6483.37 8079.50 6533.34 8143.62 57.00 2522.25 3334.50 4146.75 4959.00 6583.50 8208.00 57.25 2536.89 3356.28 4176.67 4995.06 6633.84 8272.62 6684-37 8337.50 6735.09 8402-62 57.50 2551.56 3378.12 4204.68 5031.25 57.75 2566.26 3400-03 4233.79 5067.56 21 to 1. Depths. 8320.00 9672.00 52.00 8392.65 9767.68 52.25 8465:62 9843.75 52.50 8538.90 9930.18 52.75 3 to 1. • 8612.50 10017·00 53.00 53.25 8686 40 10104.18 8760-62 10191.75 53.50 8835.15 10279.68 53.75 8910.00 10368.00 54.00 8985-15 10456-68 54.25 54.50 9060-62 10545-75 9136-40 | 10635·18 54.75 9212-5010725.00 9288.90 10815.18 9365.62 | 10905·75 9443.65 10996.68 9520-0011088·00 9597·6511179-68 9675-62 11271-75 9753.90 11363.18 55.00 55.25 55.50 55.75 56.00 56.25 56.50 56.75 57.00 57.25 9832.50 11457·00 9910-40 11550-18 9990-62 11643.75 10070·15 10070-15 | 11737.68 57.75 57.50 c c 2 356 1 Depths. 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9:00 1 to 1. 4 13'00 13.25 13.50 13.75 31.25 63.00 95.25 128.00 161.25 195.00 to 1. 31.50 64.00 97.50 132.00 BASE 31.-Sectional Areas in Feet. 4 to 1. 167.50 173.75 204.00 213.00 229.25 241.50 253.75 264.00 280.00 296.00 299.25 319.50 339-75 360.00 10:00 335.00 360.00 385.00 410.00 11.00 371.25 401.50 431.75 12.00 408.00 444.00 475.00 462.00 516.00 31.75 65.00 99.75 136.00 445.25 487.50 529.75 454.60 498.46 542.42 464.06 509.62 555.18 473.51 520-78 568.05 483.00 532.00 581.00 492.51 543.28 594.05 502.06 554.62 607.19 511.53 565.98 620.35 1 to 1. 14.00 14.25 14.50 14.75 15.00 521.25 577.50 633.75 15.25 530.88 589.01 647.17 15.50 540.56 600.62 660.59 15.75 550.26 612-28 674.30 32.00 66.00 102.00 140.00 180.00 222.00 266.00 312.00 572.00 586.31 600.74 615.31 1 to 1. 32.50 68.00 106.50 148.00 192.50 240.00 290.50 344.00 400.50 460.00 522.50 588.00 2 to 1. 630.00 728.00 644.81 746.34 659-75 764.88 674.71 783.44 33.00 70.00 111.00 156.00 205.00 258·00 315.00 376.00 441.00 510.00 583.00 660.00 656.50 741.00 674.09 761.87 691.86 709.84 782.98 804.37 826.00 847.87 870·00 892.37 2 to 1. 33.50 72.00 115.50 164.00 3 to 1. 34.00 74.00 120.00 172.00 Depths. 1.00 2.00 3:00 4.00 217.50 230.00 5.00 276.00 294.00 6.00 339.50 364.00 7:00 408.00 440.00 8.00 481-50 522.00 560.00 610.00 643.00 704.00 732.00 S04:00 9'00 10.00 11.00 12.00 825.50 910.00 13'00 849.58 937.43 13.25 874.10 965.22 13.50 898.90 993.43 13.75 924.00 1022.00 14.00 949.40 1050.93 14.25 975.12 1080.25 14.50 1001.10 1109.63 14.75 15.00 690.00 802·50 915.00 1027.50 1140.00 705.31 821.59 937.87 1054.13 1170·43 15.25 720:75 840.88 961.00 1081.12 1201.25 15.50 736.61 860.34 984.37 1108.40 1232.43 15.75 357 Depths. 16.00 16.25 16.50 16.75 17.00 17.25 17.50 17.75 18.00 18.25 18.50 18.75 BASE 31.-Sectional Areas in Feet. to 1. to 1. 14 to 1. 560.00 624.00 688.00 752.00 880.00 569.76 635.78 701.80 767.81 899.84 579.56 647.62 715.69 783.75 919.88 589.38 659.51 729.67 799.81 599.25 671.50 609.13 683.51 619.06 695.62 629.01 707.77 3 to 1. 4 1 to 1. 743.75 816.00 757.89 832.27 772-19 848.75 786.55 865.31 2 to 1. 1008.00 1031-87 1056.00 940.09 1080.37 920·00 1020·00 935.30 1037.81 950.69 1055.75 966.17 1073.81 21 to 1. 1136.00 1163.90 1192 12 1220.63 Depths. 1264.00 16.00 1295.93 16.25 16.50 1328.25 1360.93 16.75 3 to 1. 1394.00 17.00 1427.31 17.25 17.50 1337.89 1495'43 17.75 960.50 1105.00 1249.50 981.03 1130.14 1278.90 1001.88 1155.00 1308.12 1461.25 1022.84 1180·37 639.00 720.00 801.00 882.00 1044-00 1206.00 649.01 732.28 815.54 898.81 1065.34 1231.87 830.19 915.75 1086.88 1258.00 844.87 932.75 1108.50 1284.25 950·00 1130.50 1311.00 1491.50 1672.00 19'00 967-31 1152.59 1337.87 1523.15 1708:43 19.25 889.69 984.75 1174-88 1365.00 1555.12 1745.25 19.50 904.80 1002.31 1197.34 1392.37 1587·40 1782-43 19.75 659.06 744.62 669.12 757·00 769.50 859.70 689.39 782.03 874-67 699.56 794.62 709-76 807.28 1368.00 1530.00 18.00 1398.40 1564.93 18.25 1429.12 1600.25 18.50 1460.00 1635·75 18.75 19.00 679.25 19.25 19.50 19.75 20.00 720.00 820.00 20.25 730.26 832.78 740.56 845.62 20.50 750.88 858.51 1220.00 1420.00 1620.00 1820.00 20.00 1242.84 1447·87 1652.90 1857.93 20.25 1265.88 1475.00 1686-12 1896.25 20.50 20.75 1289.00 1504-37 1719.63 1934.93 20.75 21'00 761.25 871.50 981.75 1092.00 1312.50 1533.00 1753.50 1974-00 21.00 21.25 771.64 884.53 997.42 1110.31 1336.09 1561.87 1787.65 2013·43 21.25 781-74 897.62 1013·18 1128.75 1359.88 1591.00 1822.12 2053.25 21.50 792.35 910.78 1028.52 1147-31 1383.79 1620:37 1856.90 2093.43 21.75 21.50 21.75 358 Depths. 22.00 22.25 22.50 22.75 4 1/2 to 1. 21 to 1. Depths. 22.75 23.50 24.00 24.25 24.50 24.75 2298.45 2603.93 24.75 803.00 924.00 1045.00 1166.00 1408.00 1650.00 1892.00 2134.00 22.00 814-51 938.28 1061.02 1185.81 1433.29 1680.87 1928.40 2175.93 22.25 825.00 951.62 1078.19 1204.75 1457.88 1711.00 1964.12 2217.25 22.50 835.64 965.03 1094:42 1223.81 1482.59 1741·37 2000·15 2258.93 23.00 846.25 978.50 1110-75 1243.00 1507.50 1772.00 2036.50 2301.00 23.25 856.87 992.00 1127·17 1262.31 1532.59 1802.87 2073-13 2343 43 867.50 1005.62 1143.69 1281.75 1557.88 1834.00 2110.12 2386.25 23.75 877.26 1018.28 1159.30 1300.31 1582.34 1864.37 2146-40 2428-43 24.00 888.00 1032.00 1176.00 1320.00 1608.00 1896.00 2184.00 2472.00 24.25 898.76 1045.78 1192.80 1339.81 1633.84 1927.87 2221.90 2515.93 24.50 909.56 1059.62 1209.69 1359.75 1659.88 1960.00 2260.12 2560.25 920.39 1073.53 1226.42 1379.81 1685.59 1992-37 25.00 931.25 1087.50 1243.75 1400.00 1712.50 2025.00 2337.50 2650-00 25.00 942.14 1101.53 1260.92 1420.31 1739-09 2057.87 2376.55 2695.43 25.25 25.50 953.06 1115.62 1278.19 1440.75 1765.88 2090·00 2416.12 2741.25 25.50 25.75 964.01 1129.78 1295.30 1461.31 1792.34 2124.37 2455-90 2787-43 25.75 26.00 975.00 1144.00 1313.00 1482-00 1820·00 2158.00 2496.00 2834.00 26.00 26.25 986.01 1158.28 1330.54 1502.81 1847.34 2191.87 2536.40 2880.93 26.25 26.50 987.06 1172.63 1348.19 1523.75 1874-87 2226.00 2577.12 2928.25 26.50 26.75 1008.14 1187.03 1365.92 1544-81 1902.59 2260.37 2618.15 2975.93 27.00 1019.25 1201·50 1383.75 27.25 1030.39 1216.03 1401·17 27.50 1041.56 1230.62 1419.68 27.75 1052.76 1245.28 1437.79 25.25 26.75 1930.50 2295.00 2659.50 3024.00 27.00 1958.59 2329.87 2701.15 3073.93 27.25 1986-87 2365.00 2743.12 3121.25 27.50 2015 34 2400·37 2785·30 3170-43 27.75 BASE 31.-Sectional Areas in Feet, to 1. */** 4 to 1. 1 to 1. 1566.00 1587.31 1608.75 1630.31 1 to 1. 1 2 to 1. 3 to 1. 23.00 23.25 23.50 23.75 359 Depths. 28.00 28.25 28.50 28.75 • 4 to 1. to 1. to 1. 1 to 1. 1492-68 1511·17 1064-00 1260.00 1456·00 1652.00 2044-00 2436.00 1075.26 1274-78 1474-29 1673·81 2072-84 2471.87 1086.56 1289.62 1695.75 2101.87 2508.00 2914.12 1717·81 2131.09 2544.37 2957.65 1097-89 | 1304·53 BASE 31.-Sectional Areas in Fect. " 1 to 1. 2 to 1. 1 2 to 1. Depths. 2828.00 3220.00 28.00 2870.90 3269.93 28.25 3320-25 28.50 3370.93 28.75 1740·00 2160.50 2581.00 3001.50 2190·09 2617.87 3045.65 2219.87 2655.00 3090.12 2249.84 2692.37 3 to 1. 29.00 1109.25 | 1319.50 1529.75 29.25 1120-64 1334.53 1548.42 1762.31 29.50 1132.06 1349.62 1567·40 1784-75 29.75 1143.51 1364-78 1586.04 1807-31 30.00 1155.00 1380.00 1605·00 1830.00 30.25 1166.51 1395.28 1624.05 1852.81 30.50 1178·06 1410.62 30.75 1189.64 1426.03 2280.00 2730.00 3180.00 3630.00 30.00 2310.34 2767.87 3225.40 3682.93 30.25 1643.19 1875.75 2340.87 2806.00 3271.12 3736.25 30.50 1662.29 1898.81 2371·34 2844-37 3316.90 3789.43 30.75 31.00 1201.25 1441.50 1681.25 1922.00 2402-50 2883.00 3363.50 3844.00 31:00 31.25 1212.89 1457.03 1701·17 1945.31 2433.59 2921.87 31.50 1224.56 1472-62 1720-69 31.75 1236.26 1488.28 1740·30 32.00 1248.00 1504.00 1760.00 2016.00 2528.00 32.25 1259.76 1519.78 1779.80 2039.81 2559-84 32.50 1271.56 1535.62 1799.68 2063.75 2591.87 32.75 1283.39 1551-53 1819.42 2087.81 2623.59 3410.15 3898.44 31.25 3457.12 3953.25 31.50 3504-40 4008.43 31.75 3040·00 3552.00 4064.00 32.00 3079.87 3599.90 4119.93 32.25 3120·00 | 3648·12 4176.25 32.50 3160.37 3696.65 4232.93 32.75 33.00 1968·75 2464.87 2961.00 1992-31 2496.34 3000·37 33.00 1295.25 1567.50 1839.75 2112.00 2656.50 3201.00 3745.50 4290.00 33.25 1307.14 1583.53 1859.92 2136.31 2689.09 3241.87 3794.65 4347.43 33.25 33.50 1319.06 1599.62 1880-19 2160.75 2721.88 3283.00 3844.12 4405.25 33.50 33.75 1331.01 1615.78 1900.54 2185.31 2754.84 3324.37 3893.90 4463.43 33.75 3422.00 29.00 3473.43 29.25 3525.25 29.50 3134.90 3577-43 29.75 360 & Depths. to 1. to 1. 1 to 1. 2 to 1. 3 to 1 Depths. 34.00 34.25 2788.00 3366.00 3944.00 4522.00 34.00 2821.34 3407.87 3994:60 4580.93 34.25 2259.75 2854.87 3450.00 4045'12 4640-25 2888.59 3492.37 1343.00 1632.00 1921.00 2210.00 1355·01 1648.28 1941-54 2234.81 34.50 1367.06 1664-62 1962.18 34.50 34.75 1379:14 1681.03 1982.92 2284.81 4096.15 4699.93 34.75 35'00 1391.25 1697.00 2003.75 2310.00 2922.50 3535.00 4147.50 4760:00 35'00 35.25 1402.89 1714-03 2024.67 2335.31 2956.59 3577.87 4199.15 4820:43 35.25 35.50 1415-56 1730.62 2045.68 2360.75 2990.87 3621.00 4251.12 4881.25 35.50 35.75 1427.26 1747.28 2066.79 2386.31 3025.34 3664-37 4303.40 4942.32 35.75 2412:00 3060.00 3708.00 4356·00 2437.81 3094:84 3751.87 4408.90 2463.75 3129.87 3796·00 | 4462·12 2489.81 3165.09 3840.37 4515.65 BASE 31.-Sectional Areas in Feet. 36'00 36.25 36.50 36.75 38'00 38.25 38.50 38.75 $ to 1. 4 1 to 1. 1440·00 1764·00 5004.00 36.00 36.25 37.00 2088.00 1452.26 1780.78 2109:29 5065.93 1464-56 1797.62 2130.68 5128.25 36.50 1476·89 1814.53 2152·17 5190.93 36.75 37.00 1489.25 1831.50 2173.75 2516.00 3201·00 3885.00 4569.50 5254.00 37.25 1501.64 1848.53 2195.42 2542.31 3236.09 3929-87 4623.65 5317-43 37.25 37.50 1514-06 1865.62 2217.18 2568.75 3271.87 3975.00 4678.12 5381.25 37.50 37.75 1526 26 1882-28. 2239.04 4020-37 4732.90 5445-43 37.75 1539-00 1900.00 2261.00 1551·51 1917.28 2283.04 1563.56 1934.62 2305.18 1576-64 1952-03 2327.30 2595·31 3307·84 2622.00 3344.00 4066.00 4788.00 5510.00 2648.81 3380.34 4111.87 4843.40 5574-93 2675.75 3416.87 4158.00 4899.12 5640.25 2702·81 3453.34 4204.37 4955.25 5705-43 39.00 1589.25 1969.50 2349.75 2730.00 3490.50 4251.00 5011.50 5772.00 39.25 1601-89 1987.03 2371.92 2757-31 3527-09 4297.87 5068.15 5838-43 39.50 1614-56 2004-62 2394.69 2784-75 3564.87 4345.00 5125.12 5905.25 39.75 1627.26 2022.28 2417·28 2812.31 3602·34 4392.37 5182.40 5972.43 39.75 39.50 2 to 1. 38.00 38.25 38.50 38.75 39°00 39.25 361 1 to 1. 4 Depths. to 1. to 1. 1½ to 1. 2 to 1. 40'00 1640.00 1652.76 2040.50 2440.00 2840.00 3640.00 4440·00 5240.00 40.25 2057-78 2462.80 2867.81 3677.84 4487.87 5297.97 40:50 1665.56 2075.62 2485.68 2895.75 3715.87 4536.00 5356.12 40.75 1678-39 2093 53 2508-67 2923:81 375409 4584-37 5414-65 BASE 31.-Sectional Areas in Feet. ? 1 to 1. 2 to 1. 3 to 1. 6040.00 6107.93 6176.25 6244.93 Depths. 40.00 40.25 40-50 40.75 41.00 1691.25 2111.50 2531.75 2952.00 3792.50 4633.00 5473.50 6314.00 41'00 41.25 1704-14 2129.53 2554.92 41.25 41.50 1717.06 2147.62 2578.18 41.75 1730.01 2165.78 2601.30 42.25 42.75 2980.31 3831·09 4681.87 5532.65 6383.43 3008.75 3869-87 4731.00 5592.12 6453.25 41.50 3037.31 3908-84 4780.37 5651.90 6523.43 41.75 42.00 1743·00 2184.00 2625.00 3066.00 3948·00 | 4830·00 5712.00 6594.00 42.00 42.25 1756·01 2202.28 2648.54 3094.81 3987.34 4879.87 5772-40 6664.93 42.50 1769-06 2220.62 2672.18 3123.75 4026.87 4930.00 5833.12 6736.25 42.50 1782.13 2239.02 2695.90 3152.80 4066.57 4980.35 5894.12 6807.90 42.75 43'00 1795.25 2257.50 2719.75 3182.00 4106.50 5031.00 5955'50 6880.00 43'00 43.25 1808.39 2276:03 2743.67 3211.31 4146.59 5081-87 6017.15 6952.43 43.25 43.50 1821.56 2294.62 2767.68 3240.75 4186.87 5133.00 6079.12 7025.25 43.50 43.75 1834.76 2313.28 2791.79 3270-31 4227.34 5184.37 614140 7098·43 43.75 44.00 1848.00 2332.00 2816.00 3300.00 4268.00 5236.00 6204.00 7172.00 44.00 44.25 1861.26 2350.78 2840.29 3329.81 4308.84 5287.87 6266.90 7245.93 44.25 44.50 1874.56 2369.62 2864.68 3359.75 4349.87 5340.00 6330.12 7320:25 44:50 44-75 1887-89 2388.53 2888.17 3389.81 4391·09 5392.37 6393.65 7394.93 44.75 45.00 1901·25 2407.50 2913.75 3420.00 4432.50 5446.00 6457.50 7470.00 45.00 45.25 1914.64 2426.53 2938.42 3450.31 4474-09 5497.87 6521.65 7545-43 45.25 45.50 1928.06 2445.62 2963.18 3480.75 4515-87 5550.00 6585.12 7621.25 45.50 45.75 1941.51 2464-78 2988.04 3511-31 4557.84 5604-37 6650·99 7697.43 45.75 362 Depths. 46'00 46.25 46.50 46.75 1 to 1. 4 BASE 31.-Sectional Areas in Feet. to 1. 1 to 1. 2 to 1. Depths. 1955.00 2484.00 5658.00 3542.00 4600.00 3572-81 4642.34 3013:00 6716.00 7774.00 46.00 1968.51 2503.28 3038·04 5711.87 6781.40 7850.93 46.25 1982.06 2522-62 3063.18 3603.75 4684-87 5766.00 6847.12 7928.25 46.50 1995'64 2542.03 3088-42 3634.81 4727-59 | 5820.37 6913.15 8005.93 46.75 47.00 2009.25 2561.50 3113.75 3666.00 4770·50 5875.00 6979.50 8084.00 47'00 47.25 2022.89 2581.03 3139.17 3697.31 4813.59 5929.87 7046.15 8162.43 47.25 47.50 2036.56 2600.62 3164.68 3728.75 4856.87 5985.00 7113.12 8241.25 47.50 47.75 2050.26 2620-28 3190.29 3760:31 4900·34 | 6040·37 7180.40 8320.43 47.75 48'00 2064.00 2640.00 3216.00 3792.00 4944.00 6096.00 7248.00 8400.00 48.25 2077.76 2659.78 3241.79 3823.81 4987.84 6151.87 7315.90 8479.93 48:50 2091.56 2679.62 3267.68 3855.75 5031-87 7384.12 8560.25 7452.65 8640.93 48.75 2105.39 2699.53 3293.67 6208.00 3887.81 5076.09 6264-37 49'00 2119.25 2719.50 3319.75 3920.00 5120.50 6321.00 7521.50 8722.00 49'00 49.25 2133.14 2739.53 3345.92 3952.31 5165.09 6377.87 7590.65 8803-43 49.25 49.50 2147.06 2759.62 3372.18 3984-75 5209.87 6435'00 7660·12 8884.25 49.50 49.75 2161.01 2779.78 3398.54 4017.31 5254.84 6492.37 7729.90 8967.43 49.75 50.00 2175.00 2800.00 3425.00 4050.00 5300.00 6550.00 7800.00 9050.00 50.00 50.25 2189.01 2820.28 3451.54 4082.81 5345.34 6607:87 7870-40 9132.93 50.25 50.50 2203.06 2840.62 3478.18 4115.75 5390.87 6666.00 7941.12 9216.25 50.50 50.75 2217·14 2861.03 3504.92 4148.81 5436.59 6724-37 8012.15 9299·93 50.75 51.00 2231.25 2881.50 3531.75 4182.00 5482.50 9384.00 51'00 51.25 2245.39 2902.03 3558.67 4215.31 5528.59 6841.87 8155.15 9468.43 51.25 51.50 2259.56 2922.62 3585.68 4248.75 5574-87 6901·00 8227.12 9553.25 51.50 51.75 2273.76 2943.28 3612.29 4282.81 5621.34 6960.37 8299.40 9638.43 51.75 4 to 1. 1 to 1. 2 to 1. 6783.008083.50 3 to 1. 48'00 48.25 48.50 48.75 363 Depths. 52.00 52.25 52.50 52.75 53'00 53.25 53.50 53.75 1 4 to 1. 2288.00 2302.26 2964.00 3640.00 4316.00 2984.78 3667.29 4349.81 2316.56 3005.62 3694.68 4383.75 2330.89 3026.53 3722.17 4417.81 BASE 31.-Sectional Areas in Feet. to 1. 3 to 1. 1 to 1. 1½ to 1. 2 to 1. Depths. 5668.00 5714.84 7020.00 8372.00 9724.00 52.00 7079.87 8444.90 9809.93 52.25 5761.87 7140.00 8518.12 9896.25 52.50 5809.09 7200.37 8591.65 9982.93 52.75 2345.25 7261.00 7321.87 3047.50 3749.75 4452.00 5856.50 2359 64 3068.53 3777-42 4486.31 5904-09 2374.06 3089.62 3805-18 4520.75 5951.87 2388.51 3110.78 3833.04 4555.31 7383.00 5999.84 7444.37 6048.00 7506.00 6096.34 7567.87 6144-87 7629.00 6193.59 7692.37 55'00 2461.25 3217.50 3973.75 4730·00 6242.50 7755.00 55.25 2475.89 3239.03 4002.17 4765.31 6291.59 7817.87 55.50 2490.56 3260-62 4030.68 4800.75 6340.87 7881.00 55.75 2505.26 3282.28 4059.29 4836.31 6390.34 7944-37 54.00 2403·00 3132.00 3861.00 4590.00 54.25 2417.51 3153.28 3889.04 4624.81 54.50 2432.06 3174.62 3917-18 4659.75 54.75 2446.64 3196.03 3945.92 4694-81 2 to 1. 3 to 1. 8665.50 10070·00 53.00 8739.65 10157.43 53.25 8814-12 10245.25 53.50 8888.90 10333:43 53.75 54.00 54.25 8964-00 10422:00 9039-40 10510.93 9115 12 10600.25 54.50 9191-15 10689.93 54.75 9267.50 10780.00 9344-15 10870.43 9421-12 10961.25 9499-40 11052 43 9576.00 11144.00 56.00 9653.90 11235.93 56.25 9732-12 11328.25 56.50 9810-65 11419.93 56.75 9889.50 11514.00 56.00 56.25 2520.00 3304.00 4088.00 4872.00 6440.00 8008.00 2534-76 3325.78 4116.79 4907.81 6489.84 8071.87 56.50 2549.56 3347.62 4145.68 4943.75 6539-87 8136.00 56.75 2564.39 3369.53 4174-67 4979-81 6590·09 8200.37 57.00 2579.25 3391.50 4203.75 5016:00 6640.50 8265.00 57.25 2594·14 3413.53 4232.92 5052.31 6691.09 8329.87 57.50 2609.06 3435.62 4262.18 5088-75 6741.87 8395.00 10048·12 11701·25 57.75 2624.01 3457.78 4291.54 5125.31 6792.84 8460-37 | 10127-90 | 11795 43 9968.6511607·43 55.00 55.25 55.50 55.75 57'00 57.25 57.50 57.75 INDEX. ABUTMENTS, 220, 222 Accidents in Boring, 35, 37 Alluvial deposits, 52 Angle of deflexion, 6 friction, 209 "" >> >> Arch, applied theory of the arch, 203 backing to, 153, 172 brick, 153, 173 >> "" 33 >> "" 35 "" "" "" 39 35 " stone, 176 "" Ashlar, 174, 223 Asphalte for arches, 177 Auger, 20 >> >> 39 "> BACKING to arch, 177 "" >> Ballasting, 156 Beton, 190 Boring, 19 >> ?? limiting angle of resistance, 209 tangential, 3 " A. with stone quoins, 227 elliptic arch, to draw, 229 >> laminated, specification for, 267 segmental arch, to find radius, 230 length of, 231 "" " to find number of voussoirs, 232 worm, 21 valve, 24 B. " tar for, 177 to retaining walls, 143 accidents in, 35 auger, 20 claw, 26 crab engine-stand, 32 jumpers, 21 valve, 24 note-book, 39 piping, 33 "" head-piece, 25 lengthening-rods, 25 Boring, piping, insertion and extraction of, 37 platform, 27 plotting, 39 pricker, 25 >> "" >> "" "" "" >> "" worm, 21 "" auger, 21 Bricks, 152 Brick arch-See arch Brickwork, 152, 172, 225 Bridges, legal regulations as to, 265 aqueduct, 264 brick, 201-226 timber, 254 "1 "" >> 11 " CARPENTRY, 154-180, 258-268 Cast-iron, 240 93 2) "" "" >" Centres for arches, 234 Chalk, 42 "" "" Chert, 45 "S sample bags, 19 spring bar, 31 "" triangle, 27 widening tools, 34 19 Clay, 43, 185 fire, 44 "" "" girders, 241 rules for calculating strength of, 243 getting out working draw- ings, 244 , in foundations, 197 13 "" C. soft, or upper, 43 grey, or lower, 43 THERE ARE iron-stone, 44 London, 44 Oxford, 43 plastic, 41 yellow, 44 slate, 47 slopes, 44 puddle, 195 366 Clay in embankments, 128 Concrete, 154 "" "" 135 "" "" "" "" "" "" Cop, 168 Coping, 178 Cross sections, 55, 78 Culverts, specifications, 179 353 "" "" setting out in sidelong ground, 116 Curves, ranging curves-Chapter I., 1 to set out tangent to two straight lines, 2 tangential angle, 3, 6 finding commencement and end of, 3—7 inaccessible lengths in setting out, 5-8 intersection of tangents inaccessible, 4 various cases of, 5 to set out by the tangential angle, 4 curves of similar flexure but different radius, 6 straight tangent between curves of contrary flexure, 6 having the deflection angle and the length of curve, to find the tangential angle and the radius, 6 obstructions in setting out, 8 ranging short lengths by offsets, 11—12 در "" "" دو "" "" "" 353 13 "" "" composition of, 187 specification for, 176 expansion and contraction of, 188 gravel in, 176 lime in, 176, 189 sand in, 188 mixing, 189 wheeling away and shooting, 190 setting out without theodolite, 13 of wing walls, 101 Cuttings-See Excavations "" 315 "" DEFLEXIONS on cast-iron girders, 288 Deposits, alluvial, 52 diluvial, 52 "" Deviations from plans and sections, 1 Diluvial deposits, 52 Ditch, 168 Dressing stone-See Masonry. EARTHWORK-Chapter VI., 119, 149 D. slopes, 120 slips, 120 INDEX. E. Ellipse, 229 Embankments, 128, 149 Embankments, sand in, 49, 128 clay, 128 "" "" settlement of, 89 Energetic-application of this term as regards the composition of mortars and cements, 193 Excavations-Chapter VI., 119, 141 "" "" "" "" "" "" "" "" "" "" Extraction of boring rods, 35 pipes, 37 "" FELSPAR, 52 Fencing-specifications, 142, 147, 167 wall, 167 "" Filling in of foundations, 180 over arches, 139-177 Foundations, 151, 197 "J clay, 185 levels of, 92 "" "" 99 GATES, 168 "" 39 precautions in forming, 129 seat of, 129, 131 "" Gneiss, 47 Gradients, 82 Granite, 46 sand, 49 sandstone rock, 49 management of, 123, 127, 132 to spoil banks, 126 for foundations, 151. occupation, 148 "J for level crossings, 148 General clauses in specifications, 135 Girders, cast-iron, 237 " Gravel, 45 F. excavations for, 151, 180 cast-iron in, 197 concrete in-See concrete wrought-iron, 237 Cornish, 46 Irish, 47 Scotch, 47 Greywacke, 47 Gullet, 123 Gypsum, 52 G. H. HEAD-PIECE in boring tackle-See Boring Hornblende, 53 Hydraulic limes, 192 ļ "" Pierpoint, 175 Piping See Boring INERT-application of term in composition of Plate laying, 307 mortars and cements, 193 Iron, 240 Pocket section, 65 Portland stone, 48 Post and rail fencing, 167 Pozzuolanas, 193 Puddle, 195 Purbeck, 54 55 "" cast-See cast-iron girders wrought-See wrought-iron ditto LAND plans, 63 Legal enactments for the construction of rail- ways, 265 Lengthening rods in boring, 25 Levels, setting out, 83 99 "" of rails, 309 bridges, 103 Level crossings, gates for, 148 Lias, 53 Limestone, 48 ·Loam, 53 "" " MAGNESIAN limestone, 47 Marl, 53 33 Masonry, 155, 224, 227 ashlar, 174, 223 block in course, 174, 225 pierpoints, 175 "" 35 I. "" "" L. "" M. "" "" Metalling for roads, 155 Millstone grit, 53 Mortar, 153, 175 "" rubble, 157, 225 dressing blocks, 224 mortar in, 224 technical terms, 227 NICKING out, 17 Note-book, or register for borings, 39 for setting out slopes, 62 N. OOLITIC formation, 48 0. PEAT, 53 Permanent fencing, 147, 167 posts for B.Ms., 55 way, 157 INDEX. P. RANGING, 1 Register for boring, 39 Riveting, 245-247 Road, form of, 170 Roads, temporary, 172 >> " legal enactments, 265 Rubble masonry, 175 backing, 174 SAND, 49 " >" " Sandstone, 49 "" "" "" 3 19 35 in concrete-See Concrete in mortar-See Mortar >> "" ور "" ** "" 35 35 دو R. "" setting out slopes, 62 >> 55 S. "" "" Yorkshire, 51 Scarfing-See Carpentry Schist, 54 Schorl; 54 Derbyshire, 49 Dumbartonshire, 50 Durham, 50 Edinburghshire, 50 Gloucestershire, 50 Kentish, 50 Lanarkshire, 50 Linlithgowshire, 50 Monmouthshire, 50 Seat of embankment, 129-131 Section, working, 55, 65 Septaria, 54 Serpentine, 54 Setting out curves 2, Northumberland, 51 Nottinghamshire, 51 Perthshire, 51 Rossshire, 51 Shropshire, 51 Staffordshire, 51 Wiltshire, 51 a bridge in a cutting, 102 foundations, 78 gradients, 83 367 368 INDEX. Setting out levels, 78, 80, 90 of rails, 309 "" "" "" "" "" "3 45 در 21 "" slopes, 56 on the square, 93 on the skew, 104, 110 springers, 117 viaduct on a curve, 113, 115 "" "" Side-cutting, 127, 129 Side drains 121 Slips in cuttings, 120 Slopes, soiling, 169 wing-walls, 98, 101 of earthwork, 120 gravel, 45 Specifications-Chapter VII., 134 on the skew, 112 slope of, 117 general clauses, 135, 161 "J Spoil banks, 126, 127 Straps, wrought-iron, 155-262 Stripping soil, 119 Surface draining, 122 TABLES, 315-322, 324-363 "" of skew lengths, 108 Talc, 54 Tangents, 2 Tar, or asphalte for arches, 177 Timber, 152 "; "" THE END. T. "" details of timber work, 158 Transverse strength, 237 rules for calculating strength, 262 constructions, 154 V. VIADUCTS, setting out on curve, 113, 115 levels, 72, 90 "" 19 W. Woodwork, 154 Working section, 65 Wrought-iron, 244 10.0″. 11.0 10.8 1.6 3.0 + A 4.6 A Stope 2 to 4.0 HHHHH 24.0″. 19′.0″. T 1 } r I 1.6 · 1 1 · ! 1 ་་ 24 T ↓ t t ↑ I e vel O if Rails 7. Ö =0 ~~ ↓ Eleva u du Above Footings. 田 ​alan. Plan 1. Ő 1. 6 + 7 6 1 6 × ± 3.6. €3.0 21. 6. Ӧ Lun 日 ​1 I 9,8 1 11:01 3.0 B. с Above Plinth と ​23.8 Published by Atchley & Co 106 Gt Russell Street, London. April 1857. 1219051766-1 D Slope 2 to 1 Ꭰ 1 | 1 <2.6% ". 2.6. J.R.Jobbins. · Longitudinal Section th H 3 6 Slope 2 to 1 HI! 17 6. I 1 1 CU₂ Section at B.B. CO GS, 1 * x3 x 6 Section at C C. 2 6 1.3 0 Scale 10 Feet - Inch आ B Published by Atchley & C° 106 Gt Russell Street, London April 1857 Section at D.D. Section at A A. 1.0 26. 5′ 6 +16+ HAHAH 6 JR Jobbins. וּי * i Levele Section. through Wing at A. Curved Batter 2 ins per foob. मध -- 6 ... 2.3 2.8 .3.0 3.5-- 3.9 4.2 4.6 4.11 5.3 5.8 6.0″ - Longitudinal Section at E. F. 1.6× 3.6 of Half Transverse Section at D. Puddle 2.0 ×1.6 20.0 1 ×1.5 × 2.0 × 2.6. Slope Rails 70% Level 14.0 25 x Ő • 6.0. 21ő kő D 30.Ö E : Rails" } κοτυτυα : ×9´H e 6.0 7.0 6.2 --- ‹ 2.31 Half Elevation. A Half Plan、 Stope I th. Published by Atchley & Co 106 Gt Russell Street, London. April 1857 ! į 1 ! ! Scale 10 Feet = 1 Inch. : Pl. 2. JR. Jobbins. Half Transverse Sections. N°1. 75 6.6. D No 3. N° 2. 7.6 7.6 Section thro'. Pilaster. Xx 1.9 6.0 f 9.0 :9.8. i Elevation. } Level NEED ! 2.0 ×1 6 10×1.0. * 2.2* 15˚. Ő Plan. of Rails. ←· 2.6 ± +2.2 + Scale 10 Feet = 1 Inch. Scale for Nos 3 & 4, 3 Feet -1 Inch. *2.0 6'. Ö - جهةة Published by Atchley & Co 106 Gt Russell Street, London. April 1857. ! 1 PORTATIONS. Section thro' Crown of Arch. 2.6. MAMAH -2′0- No 4 Pl. 3. J.R.Jobbins. 2.6 • 6 ،ހނއނ 9.3 I 20.Ő ·D.. V me Kessiew KORT Level 乙 ​Elevation I 3.0* 2.20.0. 24, 0 of Rails 14.3 Balance Tune. • 20'.Ö Longitudinal Section. } f slope 90. Ő Scale 10 Feet = 1 Inch 19.3 Plan above Coping. Published by Atchley & Co 106 Gt Russell Street, London. April 1857. I 1 I 1 20.0" # t J J F • I 1 } 14.8 1/% to 1⁰ 1 1 W R a 1 Half in open Cutting N° 2. で ​1 Radius Level 24.3. I 20. Ő S Sections 12. Ő 240 9.0 off 30. 0° in Tunnel Nº 1 Rails HER J 3.0 2.0- 2.6 : J.R. Jobbins. Pl. 4. 1 • MANA Sing ne 9 1 0½ Elevation. 12 2.3 6. 56 0 Plan # # · ! C Br Published by Atchley & Co 106 Gt Russell Street, London. April 1857. 2.10. 1 sha Sandra IT 20' JR. Jobbins. 1 1 Section through Retaining Walls. Level Section through Tunnel Front. 1.6 HP Scale 10 Feet of 1 Inch Published by Atchley &C. 106 Gt Russell Street, London. April 1857. Section through Pilaster. A ; Rails • Pl. 5 a J.R.Jobbins. i / 1 3 ////////// Half Longitudinal Section. __4_9″__ O 23. 01 on square. Slope \ 2 to 1 Angle of Skew 75+ Half Plan above Footings 23 0. "1 13. 0 on square. Pos Road Line Apl Scale 10 Feet 18′0″ on square. 1 Inch 1 1 I 1 1 4-26 0 # "7" 4%B 1 1 1 Daikhshad bar Atchlev & Cº 106 Gt Russell Street, London. April 1857 1 1 $ 1 1 23 Q on square 2 to 1 1 Slope Half Plan under Coping + ܠܠܔܔܢܜܔ 12′ 6″ • I 90 28 0.. I ___6′ 0″___ Road 12 6 8.0%. " Iine Stone Skew backs 'Half Transverse Section 1 1 1 · 1 $ 1 8′ 0″ 6. 1 F 20 8' 0' JR J¹· 2'1' 2′ 6″ #1 45 4' 10 30 19 1 1 I Slopes 0" In c l i n a t r o n 1/4 to 1 Concrete -*· " 5' 2' Xx Longitudinal Section I V n I r n e е ef 5′ 2″ 5' 7' 8' 30' 9* TEKER 8 H 30 ་ • 1 of ~~0 Transverse Section. 14 9 12' 3". 0,8 12' 0' Road Ir ne #1 11" ic 4 7" Re R a r l s a a Rails Concrete K-- Published by Atchley & Co 106 Gt Russell Street, London April 1857 - 5. 2". 54/2 5' 9/2 5.11. zn I 19 20 ↓ 72 t 0" Scale 10 FU Alg 1 inch 13" ---- 1' 8" 1 101/2 1' 8 "/ 2 1 2 6 3 0" 4.0" JR Jobbins Pl 7 Surface Slope A½ to 1 Batter 1 in 5 Line Section at A. Half End View. J.6: 13. I i ne Half Transverse Section .2.6.. 1.6 4.17% 2.0 434. Centre Lin n e Road of 28.ő of 3.6. 1 25 1 16′. 3″ 1 ! Half Longitudinal Section. Ra il s Half Elevation. ܚ Iine Half Plan of Foundations. at Surface Line. Section at C.D. с D Scale 10 Feet - 1 Inch. • Published by Atchley & Co 106 Gt Russell Street, London. April 1857. Rails of Railway E/ A B Pl. Vill. Section at R. C D Line Line J.R.Jobbins хо Sq u ar e 14: Piles 18 O EI. D 口 ​C la p -* D el v natio ひ ​7'8 Ꮽ v Z ם 口 ​. z z PL ם D 모 ​Z KE Z NJ D - www www a 人​, ים "} 12 X 10 O Ra 40 +X+0 10 'x TRUSS FOR A 30 FEET SPAN. I LII 6x4 in 50 6.9 b 1 D Skew span 33 feet & 30 feet on the square 675- Strut ☐ ם Transvere Section on the Square Elevation ם 0x LI 26' é 12 6' ő planking A NA ZS 0 T - | X 5 0 D ם 12 X 10 6.9 ច Try Published by Atchley & C° 106 Gt Russell Street, London April 1857 10 m کہ D ធ D ㅁ ​1 ☐ X O D 口 ​ப ם wh ㅁ ​+ 11 f J.R.Jobbins ! • • Enlarged view of Scarfing & c. 14 12 10 k Op 34. J t 1 T 12 14 دگی 11. Pile 14 Square TT t + bolt Cast Iron Work at b. + I 1 1 12 3 4" Fig 4. 1 1 l' pins →→ **2 DI 13 long between Read & Bur 1 holes dram? 10 1 ! 1 Details of wrought Iron Strap at Foot of Struts marked (a) NB The dotted lines represent the Strap for the Struts marked b 13 薯 ​I • I t ! 1 Axx cx_ 1 3 Strut a <*** 、 ה! badad 諗 ​Published by Atchley & C° 106 Gt Russell Street, London April 1857 * ܗܘ ܗܘ ܗܘ -=-=-=-=- Scale 6 Ft-1 Inch. 17 #1 U གནས་གས་ ་ ་ གས་ ་ མ་་ ་ ས་ ----K PI. 9a JR Jobbins. 13 -13 1/2 Bolt = => 13 10 Bolts 1/2 x- · 1 13- ×-13- A BERERE DE 40 Feet B " " }} Scale 4 Feet - 1 Inch 40 FEET TRUSS. Elevation 1 }} Published by Atchley & (°106 Gt Russell Street, London April 1857 C D 208 ↑ -ই Pl 10 Cantlevers to be foced on the head of the piles by 5 spikes 12 long to each. JR Jobbins <- سے 13 "1 12 " Level 13 × 6½ 12 × 6 Section at A.B. 14′ 6″ of #1 13 O 13 5x0 ㅁ ​イグ ​170 14 } } } 1 1 ↓ 1 20 3 Section at C.D. 14 6 Ravls 13 × 6/2 #1 13 2. Š O 13 ㅁ ​[ 13 x La 12 +92 12 Scale 4 Feet to one Inch Published by Atchley & C° 106 Gt Russell Street, London April 1857 13 -> - ㅁ ​12 Pl. 10 a 91 16″ 6: Casting × 15 12 12 12 5 at B. Scale 4 inches 1 Foot . Enlargements at xx 15 16" 7' at A & B 16' . "1 16 TRUSS FOR A 40 FEET SPAN. x 15" A , 16" x 16' ☐ } 1 { } } ㅁ ​TOT 向 ​I U "1 16"- x 15 14 16° × 16" Transverse Section. 15' 0" ㅁ ​C B Irne Elevation. Published by Atchley & C° 106 Gt Russell Street, London April 1857 10' 6 of 40 Scale 10 Ft = 1 inch 16' 0" 16". B Rails 16". JA 1'. 5' • A Casting A at A Scale 4 inches = 1 Foot Scale 1/4 of an Inch - 1 Foot w Pl 11 JR Jobbins The ← Straps 3x72 # 1 I e v Joist notched on 2 "/ е 6 7 10 6 "} 15 x 9" Cast Iron Shoes 1/2 thick 12 6 15 × g 乙 ​# to the Sectio I →→ f Principal 15" x 9 15 × 9 X X × 4 R a i 4 × 7/8 xo Z S 26.. 15 x 9 15 × 9 1 146 I e 15 × 9 15×9″ 4.4 TRUSS FOR A 44 FEET SPAN. 7 Elevation. Tumbers in parapeb 4" square Board ½ thick Board 1% thick Cast Iron Shoes Wrot› Iron plate 12″× 9"x1/2″ 15×9″ Key holes 34x1" 5 of Iron below Keyholes 〃 Scale 5 Feet = 1 Inch Published by Atchley & C° 106 Gt Russell Street, London April 1857 -- 5' 6 6 Ő 6.6 6.0 S xx I e vel Ashlar 2' 0" 19" " Cross Section 16. 12 イグオ ​of 15" x 4 17" x 9 " 12 × 12 18′ 9″ R a i l s 19 Ashlar D Pl. 12. JR Jobbins · · ❤ 19½ botts #1 4 x 4" " } Τι пе 1 Details 6 Q O 1. 20 at A . of I '5″. 77 LO ·1.2 - - - - - 6 1 1 6 ! 1 4″ × 4″ Rails 1 Scale ½ an Inch to one Foot. Published by Atchley & C° 106 Gt Russell Street, London April 1857 1.0 -1.2-. 7/ 4 X 4" K-- 12″. 10" 12" × 12" 42 --1.2. Pl.13. · J.R.Jobbins. 1 12" × 12" 4'x4' Details I i ne -XO, IX W 10- If bolts- 12 0 171 "/ at B 2 5 f= # 5 1 کا چاه 1.0. q Y "1 6 O Q O 4"x 4" Παντς " ↓ H Z ine D B 17700 4.4″ Elevation 50 feet Scale 12 Feet - 1 Inch. - -5′3″ J 1 Raits. ~Let F Half Transverse Section QUUUUUL If½ bolts Ꮮ Z 6 ó 12″ × 12 "/ ވ 1 at C.D. n е For details - Scale 1/2 TRUSS FOR A 50 FEET SPAN. an Inch - 1 Foot Published by Atchley & C°106 Gt Russell Street, London April 1857 1 1 о f 1 250 4 8 Half Transverse Section at E.F R 8″ x 8″ a z " =∞0×80 14' Z 1 ½ ----16 10 1 1.2. ហ 14 3 6 -1 1 - 12″ 6" { 1 1 1 1 40. 6 br اور Ht 12 Batter in 30 JR Jobbins PI 132 1 " # पद 1276 12×12 16×8 16×8″ 6 × 4 Level 12×12 " × Co カメヤ ​16×8 }} 16x8 tal ם ㅁ ​#1 12 X 11 12 O O 14×8″ # 1 I #4+4 е Half ν е N° 3. Transverse Section Z 14 × 4/2 12 × 2 12 × 6 12 × 6 12* × 6 0 14 × 8″ X 8' x 5 No 2. f 12 × 6 Elevation of Inner Rib of K 14 X 0 4 Scale 4 Feet - 1 Inch = •x .::5 --ribe R 5 × 3 11 a - O A }} 12 X 11 12 [O 14" x 8 z z // 7 x 4 Published by Atchley & C° 106 Gt Russell Street, London April 1857 || イメーズ ​16x 8″ S 11 6 x 4 1 1 Ra v l s 12×2 Fi. 14 d JR Jobbins. C Stone Step W по O N Akan mulan Mudge TIMBER FOOT BRIDGE WITH CORRUGATED IRON SCREEN. " Note. Wrought Iron Straps 2½ x 1/4" and 3/4″ Bolts. X n 3′0″ THE TWO TRUSSES ARE 8 FT APART. Cor wg Elevation. z e d I ever of I ron 15 t 12"x 8 × 4 r e e n Ra v l s Published by Atchley & C° 106 Gt Russell Street, London April 1857 พ S › by man Z JURNA ↑ Scale 10 Feet es 1 Inch. 7" Pl lb. J.R Jobbins N ↓ ax 8. 12 X 1236 1 2 × 1 2 Cast Iron Boxes for receiving the ends of the principal Rafters. 4X4 1 }} 16×8 16x8 1846 12×12 12 X 161 TRUSS FOR A 50 FEET SPAN 1 Elevati on Scale 1 Foot -1 Inch for Nos ja 2ª & 3 a Scale 10 Feet - 1 Inch. 50 Feet Sect 1 on 6 x 4" N° la No 2a Plan I ► N° 1 Enlarged Half Elevation of Outer Ribs 14 × 7 е 乙 ​14 x 8' =20 diam! 12½ 25′ 8. Scale 4 Feet - 1 Inch 0 f 14 ገባ 5x Published by Atchley & Co 106 Gt Russell Street, London April 1857 7*4 12″ × 7 6x4 V "} "1 16×8 No 3 a Enlargement at A し ​S | | 12 × 2 TR b } 1 } + 6 x 6 3/20x ** 9 Two 1/2 bolts st one -3′ 18¾½ - } +4/2x4/2 1 Rise 1 in 5 472 472 36 0 $7/2 X Half Elevation. 12″ × 6″ 6. Ő TIMBER FOOT BRIDGE 68 Scale 4 Feet - 1 Inch. 6 x 41/2 Q * Four/%" bolts Ú is 34¾½-- ! C 1 12′ Ő t VA } -- 6.0. Published by Atchley & Co 106 Gt Russell Street, London. April 1857 I e 1 V e v 6.0 18.Ő D 16.34 of B a l a n c e C 6.0 R a i l s I i n e 15 0 " ·4 ő- S t o n Ø - JR.Jobbins. Pl. 16 3.6 Towin 33.0 26′. Ő t 1 1 1 } I ! 1 1 Į Cross Section of Bridge Surface P w d of G 1 1 } } 1 1 1 | 1 I ! 44.0 I I 1 Present Surface of Ground Į Water d i e Path Scale 10 Feet 1 Inch Published by Atchley & Co 106 Gt Russell Street, London. April 1857. /// I Mattel M ¡ i ! IKE Half Elevation. 12.0 AQUEDUCT BRIDGE I o ! w i n g I 1 1 ( 1 1 1 59′. Ő C e Pa n + Sadaka pa v kad ga v s m J Mad Maga Pla TITI z h tr 1.6 L То 33.0 li W 11 59'. Ն ļ I N 9 2 f 0:9 F ↑ 1 I I 1 1 Po a I ¡ ! Ե i a h N Ő 153 773) Surface of Rails a l 32′.0" JR Jobbins. Pl.17. 33 33 Surface atat 09 of Rails Half החזות 7 Surface of Longitudinal P C o n c rete C e W d 32 Ő Water TV t r Ե 33 ő ď Z е @ 9 ና 40 & I I } 11 Ő I I Section All the Fe AQUEDUCT BRIDGE. Fekk == q + + F F F A++ #++ = = x + Haq x <- 10.0. Plan o f 32' Ö Scale 10 Feet - 1 Inch 26 Published by Atchley & C° 106 Gt Russell Street, London April 1857 < с Section at A.B. 1 I I 33′ 0″ 1 1 1 ! I 1 I 1 # ! I I a 5'0 59' 0" TV 4'6 ου Z B A 59' 0" Pl.17. A 187 JR Jobbins * } Level of Towong Path Slope of Embankment Foot of Slope 02 看看 ​19-- 5.7% -23.. 1 1 I I 16 Ő 1 1 I I I I I • I 1 1 0 1 ! 1 1 I t 1 I I J 7 | ..b 2 co Half Elevation 53 e_ Į ! 1 CAST IRON AQUEDUCT BRIDGE. 10 41 T o w v n g e...... 1 P r c po s e d 3 Path 56 v r d er > 10 |||||||||| [m] I o w i n P- Gur der To V e ve l I Section at gh Pat h for Scale 4 Feet = 1 Inch. K Ro a d Published by Atchley & Co 106 Gt Russell Street, London April 1857 1 { ļ " Half Section. 36. //////// / / / / / / / // 6 6. /////////// / / / / // ///////, //////// Towing Path / / / / / / / // //////// Pl 18 JR Jobbins pal, legat dan vande de alta cara prin allega dad de la p dar village had to add to t Gurder a W 27 I 8 I =m I } I 1 1 1 1 } 1 | I 1 1 1 # 16′ Ó 1 1 1 1 I · 1 1 1 Water 1 } Section at ef < 14/16 F www. Bottom 0,2 L e ve l - Nac Plates Top of Counterforts 7 Section at ef TÓ P u d d l e Present H of O { Surface Level of Water Canal in A q u e d u c t P Abutment Plate at x. } 1 I I I 5′ 6″ ✰ 14″ Ο 4 O I TH 1 12 1 [ Firefor tore forest Level Plan of underside of Bottom Plates of Aqueduct. Scale 4 Feet 1 Inch Scale to Enlarged Parts 2 Feet 1 Inch Section at ab O of 5 Published by Atchley & C° 106 Gt Russell Street, London April 1857 Cover u n gi∞ 6' 8 I o w v n g 9 10 ! 1 P l a b e Section at c d 6' ő Towing Path. །། Path 12 X Level of Water 1 I Bottom of Canal Section at c d Level of Towing Path < 0 + I - K [ 1/2 10″ 12 < 2½ > JR Jobbins 6 09 1 I C t 19. 721/20 -→ I 1 ľ 4' ő 80 3 ő g ✨ 2 ő 2 Ő × 1 Iine of Foot of Towong Path Wall Iine of Towing Path Wall(Coping) 4'. 9 I o w v n g 4' 9 = X. .-5′-6″-- OC Path A q w 1 Dobbet Wo LE e dz c t A q w e d w cz 5' 6 -5-6- h Centre Plat 33 9 Plate 1 e s I Plan. I v ne S I t t Covering Plates 0 1 I 1 31 of of Towung Canal A 15 0° 31.1 d Path G i r der G v r d e r i Scale 4 Feet 35′ 9″ 1 Inch X 4′ 3/4- X 4 34 Gurder G v r der } G r r d er Published by Atchley & C° 106 Gt Russell Street, London April 1857 Fo \\\\\\\\\\\\\ \……………\………. 2.0″ f 1 +4 < - 20 L A F Pl 18 b HHHHHH JR.Jobbins M ↓ Vegetable Soil Turf Moor Sand Gault } 1 Sood 1 I ! .. 30 0´..... F } 凹 ​30'0 FF lowing 1 6'0.. THE Path KIM O 16 . 口 ​O 口 ​♫ D O a Half Plan of Bridge Complete V ♫ TO Le ve l ሩ 1 يام 10′0″ a. 12'. É of Elevation 30 Բ W a te p +40 • DKI DK Scale of Feet O D པ 51 • • DIKI KILL ▸ 33 BRIDGE OVER THE RIVER OUSE AT HILGAY, DESIGNED BY J S VALENTINE CE 1847. Q DK CRICK • Published by Atchley & C° 106 Gt Russell Street Londor Apri 185 • MIM Half Plan of Tumbers A p XK DAK KILIKI 2 15 O K O Ill → Q ミ ​Two thicknesses of 4% Fir Planking O GO > O Q DE NE • 13 O 미 ​ե C 1 30′ 0″ • Peet Gault 13 O } • ...... .30.0 ་ { I I HT → • Pl 19 Section of Capping on Bow Section shewing Abutment Plates to Struts and Plate to suspending Rod co. 36 " 2 BRIDGE OVER THE RIVER OUSE AT HIL GAY I S Valentine Engineer 5 Ó 12'× 9* K 1--- I 12inch 5 14/17 O 4/2 6 K-- O O 7 Scarf to Beams of Bridge" full Size + Cross Section. Scale 4 Feet = I Inch 10 1 26 ő 1 910 Suspending U O 5 t I I 1 t ↓ I Scale of Inches and Feet Q O + 1 f J [ 1 Rod O O ↓ T D L=d 5 0 12 × 9" X Published by Atchley & C° 106 Gt Russell Street, London April 1857 , о оч O O 1 I ¦ 1_ 5 Feet -X- 20. 36 PARVAN ļ Pl 19a JR Jobbins 12 Plan of Abutment Plate for Struts 6 O 2 2* 1 ช่ 2. CONS Elevation of D° - 14/2 3% ड 8 Double End view of Abutment Plate with Struts fixed =10 -- 2/17/1 Plate on Bow for Suspendmg Rods " 2 2 End view of Shoe 12 Scale 1/2 Inch to 1 Foot 2 ? º 24 ♡ 个 ​2 2 Suspending Rods - イイ ​51 22 Plate under Tie Beams for Susponding Rods . # 2 2 6 1+ Abutment 6 Fb 160 24/4A 2 ng for Outer Bow BRIDGE OVER THE RIVER OUSE AT HIL GAY DETAILS OF IRON WORK. I S Valentne Engineer Elevation 6 1 Xó ģ .. for Inner Bow O -- ' A= 2.2 Plan of Covering Plates. 5 22 12 30 In Ө O 1/4 130U 5 * 9 10 62 " ข Section at a b Publihed by Atchley & C° 106 Gt Russell Street, London April 1857 Will of Shoe O O 1 Į Plate - 3 - - A 2 2 22 Plan of Shoe о 20 19 2 • I t 督 ​10 10 End view of Shoe with Section of The Beam Pl 19b JR Jobbins 2 FEET CULVERT 9 Section Gravel Elevation 16. 1'6' 2 ő on edge 16 FOUR Longitudmal Section " 8′ 0″ -- 16 in Cement Section 1½ B ← FEET B 3131/18 40 3.0- I 1 + 1 29. York B -17/2-- 2 É - V B / # 16 BAR > CULVERT B 17/2 Plan B 1½ } 1 1 } I 1 Į I Cross Section 4.0 0,2 7%B Longitudinal Section 1% B 16 d 1 8 0 H Scale 4 Feet Plan со 1 Inch FRAMHER Bala 5 3 B- FEET of Entrance ź 6. 3' 6'---- Published by Atchley & C° 106 Gt Russell Street, London April 1857 1 ? 1 CULVERT on edge vn 1 ..2 6 Elevation vn Cement A Cross Section Elevation 104 on edge in Cement 3 ö Batter i'th per Foot 2 6 13 Pl 20 JR Jobbins f 28 3. B * 12.0" Q Plan. 12.0. Slope 1½ bo 1 6 } 2.3. <-- FEET 1/2 B H 3 B E m b a n k m e n t Cement # 65. Ő 0 128'. Ő I 3:0 I + 1 i į CULVERT.. Elevation. ! on edge την 2. B 1/2 6.6. 6.0 Cement Cross Sections. 6 1 1 D 20 blad 3.0 ސ 12′.0″ BB Scale 4 Feet 1 Inch Published by Atchley & C° 106 Gt Russell Street, London. April 1857. | THERE ARE → 1111 ·8.9. Cọ 2. + I t I | t 1 TV C T e te t 1 1 1 6. Ő. : : *CO ( I Pl. 20.a " J.R.Jobbins. Slope's in 20 10 0 # Surface of Ground Scale 6 Feet = 1 Inch q f птолет похолат 1 Ballas ૨. C 10 ← 10 51 mit ő EX GATE FOR 5 FLD Bålla st i Longitudinal Section 1 LEVEL Fransverse Section 5.4 MĚZAVAZÁVAVAŽNA " { I CROSSING. Pan Y UNS 2/9 x 8 < @beg Ballast 0 이 ​O 5 Ó . . 8 Published by Atchley & C° 106 Gt Russell Street, London April 1857 * allas • 8' Ő 0 0 0 D -- 68 - Road Material | 1 3 4 ģ 20-28 1 ↓ I : 18.6. O 1 O Surface of Roadway 20110 15′ Ö Pl 21 JR Jobbins 10 X 10 #1 у • 30 1 mx O 3.0 • O TALK Strap 2 1 · 1 1 1 I 1 I I 1 1 | j z } + 1 X 9 12′ x 6" J " ^ 12 # 04/2x40 1 Ask-L} 3/16 drameter 6 ő 3″ × 1¼/4 1 3 x 4 × 4″ X 12±6 J 3 x 1/4 :0 }} 94 bolts TURNPIKE AND PUBLIC ROADS. GATES FOR LEVEL CROSSINGS. Elevation 25 6 A 1 F I 1 1 I Cox 00 = I 1 I "4" x 3" [ | I 4 × 3″ រ 1 Rivets Details A and B. Scale 1 Inch - 1 Foot cox O Published by Atchley & C° 106 Gt Russell Street, London April 1857 Plan 25' Ő B 1 I 1 B 1 1 1 1 I I 2" F 1 I I 1 1 t } T 1 1 1 1 1 } Scale 2 Feet = 1 Inch T T 1 TOD O 100 ་་ om O | 2 00 O 1 7 I In M/½ pin: કા Pl.22. JR Jobbins A الا وصال ↓ 3′. Ő ott & 1 JR Jabbins 12 Xx∞ 12 "1 12 12 12 Pin 7/2 × *** XSD 4.6 O 4 x 3 3 × 1/4 O Iron 2½ × 3/8″ B 3×17/4 X 3 × 11/4 OCCUPATION #7 34 bolts Plan. 11.0″. 4.3. Elevation 15 6.3. • ROADS 10. 3x3 3 xQ Published by Atchley & C° 106 Gt Russell Street, Lordon April 1857 9° 9 Level of Ravi s Scale 2 Feet = 1 Inch. W Pl. 22 a + + 96 ! 1 1 1 + 1 } 1 O O Rails Scale 10 Feet = 1 Inch Elevation. O O 10' 0 4'6 f O Scale 2 Feet - 1 Inch. Plan. 10 × 10 O A pin 174 1 Ο 4 GATES FOR LEVEL CROSSING O } } 1 1 1 1 Q O O Q XRT FIELD 5.4 4.8 9,1 2. Ő ROAD. 3/2½ x 1/2 Slope 2 to 4/12 X Published by Atchley & C° 106 Gt Russell Street, London. April 1857 The width of the Top of the Embank must in all cases be 6 Feet more than the width of the Bridge within the Parapets of Road wa Metallumq min Faggots от 1 1 1 t 董 ​Section of an approach to a Bridge Scale 1/4 Inch = 1 Foot } 3/2 × 1 3 1/2 x 1 Scale 5 Feet 1 Inch 3/2 × 1 X O =α0 Brushwood N J I 3 × 3 3 Slope 2 to Pl. 23 JR Jobbus ! Ե по о A O 00 P C E D B D U L O A о Fig. 8. O O V Fig. 9. D ΟΙ O Ꮴ о O G O O O P Ο Q O ☺ Q Q P Fig. 5 Q O 1 TO ! 0. } } Fig. 4. 1 A ig. 1. O O Ο A o O } I F P P P B 103 P O B WROUGHT IRON GATE ए Fig. 2. F G Fig. 16. O O R Q: ᏚᎴ Q OS Q Fig. 15. ¥ O 01 O 00 ↓ N K P Fig 12. L Pubnshed by Atchley & C° 106 Gt Russell Street, London April 1857 { I T 5 C 串 ​1 算 ​盏 ​! a O O Ο Fig 14. I H Ο H Q O Fig 13. O Q: Q Fig 11. H @ 10 of Vio O O G O • 0 F W D Ca 2 B2 [ Fig 10 Oak Pos t A2 "/ A2 O "1 O I "// A ga Fig 6. B 2 • 0 1 1 ! | E2 F1 g. 18. Fig. 17. Scale for Fig. 1.2 17 & 18. – 5 Feet - Fig. 7. 1Q C C F2 " 1 } 1 Q .P O Θ ΟΙ O O To d O O 0 Q 0/0 1 Inch 4 5 6.7 8 9 10 11 12 13 14.15 & 16 A FC = j Inch O O O O O PI 2. о о Fig 20 to о 1 XXX Fig 21 [ADDOOOL O Scale 4 Feet · 1 Inch Fig 22 ……………… O [ Published by Atchley & C° 106 Gt Russell Street London April 1857 JR Jobbir небритые мон A.. 4 Tive Drain Porch .. 2.10 I 5 11½ } 4. 9/2 4. 3.3 4 Tile Drain 2.1 1.8/2. 1 N N 2.3 1.2 Inch proper ledged Door with rounded linings both sides, Thumb Latch 316 7.4 3.3 Living 12′.8" 4.0 9" Quarry Paving in beaten Mortar. ♡ ROADSIDE STATION. Booking 12.6 12′. Ó 4 Quarter Partition 2.6 RooI Counter Ground Plan. ģ m Office gő 11/4 Yellow Deal Floor 128. 上し​ap 2.3 5.8 Bay Window 1 2.12. 4.6 York Paving 1 3.Ö 4.0%-- Inch proper ledgedi Door with and rounded lining next Closet Architraves next living Room 3.Ő 4.Ö t } + 1 1.6 I 1 1 1 Cast Iron Oven 1.6 4.4. ·3" York Step 1.1ő¼‰ Copper 1.2.1.6 42 Quarter filled in with 4 Tile Drain 3.3 3. 2¾½ -- Inch proper ledged Door rounded linings both sides 6 Fron Lock 8.0 Washhouse Brick on Edge Paving Sink 2′. 9" Published by Atchley & Co 106 Gt Russell Street, London. April 1857. partition Brick nogging Pantry Brick on Edge Paving D I 3'.9 1 =00 -4/4/ 2.3 ! ..B 4" Tove Drain Scale 4 Feet = 1 Inch. 4" Tile Drain T TR Jobbins. Rainwater pipe Pla i n Tiling 6.6 # I t Chamber 3.2% Inch deal Folding Floor Quarter partition Sill 4 × 4 x Quarter partition Sill 9 × 4 ? : molded Į. Plan Inch deal Folding Floor 3.2/2.. Zinc Gutter 2.5 NV 1.619 1.2 SW. Lead Hips flashing to ridge • N.S g ROADSIDE STATION. Coping Bricks in Cement 5.5½. Y Rain water pipe } 6 Cou • P l a i 1 I i l i n g 22 Courses р Door Frame 5 × 4 Scale 4 Feet Sof 22 Cast Iron Rainwater pipe Gutter 4½ Cast Iron Eaves X Posts 4/2 × 4 Purlin 5×4 Z Rafters 4x 1 Inch. Head 4% × 6 leiting Torst 5 Head 4/2×4 Brick on Edge :00 18 Courses *13 Courses. Wall Plate 6x51 returned all round the Walls 2.3 Published by Atchley & Co 106 Gt Russell Street, London.. April 1857. I 1 ! u?? Veiling 9 Section at A. B. z ž Wal plate 4x3 returned all round the Walls Common Rafters 4/½, -Ridge 9″ × 1½ Collar है x 3 Ter Ceiling Jousts 3 × 2 X 8.0 Posts 4×4 Quarter 4 × 2 Principal Kink Head of Partition 6 × 4 Spiked to principal Rafters FoÿSV-7332" -Strwbted -7332″- Rafters Q ua Sill 9 × 4/2 Zdr 1 4 x Postis Purlin 6x4 + a v in g 39 Courses 12 Courses 40 Courses I Pl. 25 a J.R: Jobbins. } # 1 5.0 Cesspool 2 Fork Stone 1 1 1 I ! f 7.6 1 1 ↑ 7 C A. 群 ​2 3 2 1 in Brick ! Note The Walls and Ceiling of the Kitchen Staircase Living Room and two Bed Rooms to be plastered three Coats the Walls to be twice colored the Ceiling to be bwice Lime washed. 5'. 1 9'Barrel Drain Iron Grating 3'. 6 Wood .2.0.. 3.3 Inch Deal Floor Inch Deal Shelkon proper bearers House Brick on Edge panng in Mortar Small Cesspool GATE 2.10 ….. Oak Sill Inch proper ledged Door thumb Latch 3 and small Bolt 7'. 3 7. 6 1 I I I } Pantry in 9° Quarry Paving 1.2 1. 17/4 × 1.37/2 Ground KEEPER S 4 Tile Drain 1.6 " 17 Gatton Copper 1.6 Cast Iron Oven 1.1½- Tooled Hearth 3'. Ő ME § 3.9° York Paving 1.2 Plan. LODGE. 4" File Drain .3.5% Sunk Stone Sink Inch proper leadged Door with Architrave. mouldings inside 8 stock Lock's and 2 Barrel bolts ornamental latch Kitche 1 9" Quarry Paving in beaten Mortar Cement Skirting, Living 12.0° 1 3.0 Deal rounded handrail turned newel and square bar Bannisters inch partition to enclose Stairs K : 9' Quarry Paving in beaten Mortar Inch Deal Square Skirting 9 Inches high Room 3.22..... Ledged Door with Closet 4.9 прот 1 · 12.Ő : f : : 17 ! : Bay Window 3 tooled Door Step Published by Atchley & Co 106 Gt Russell Street, London. April 1857. 3.3 | t 1 W`6 5.11 4 Tile Drain B Scale 4 Feet 1 Inch. Pl. 26. 2/½ Cast Iron Rain water Pipe Coping Bricks in Cement I i ṛ v n g Pla i n Coping Bricks in Cement 不 ​2.3 4. 6 Chamber Plan. - i Ñ ½ G 1.2.2 1.2 прит ч 2.3 11/2-7 Tooled Hearth Back Bed Room Inch Deal Folding Floor Inch Square Skirting Thigh 2 Inch Rubbed York Hearth 2.67% 4" quarter partition, the heads spiked to Front the principals of Roof and the Sill dovetailed Inch Ledge Door at each end to the Wall Plates Bed Inch Ledge Door Thamblatch __ï.6½- Inch Deal Folding Floor Inch Square Skirting 7" high & Barrel Bolt Room I I 1 + Thumb Latch & Barrel Bolt GATE KEEPERS LODGE. 2 Inch Cast Iron Rain Water Pipe and Rage Plain T i l i n g amu ng Courses→ 1 I 15 Courses 5 lb.milled Lead stepped flashings next Wall Parlin 5x4. Rafters Pe Plate 4x3 Window Bond / × 3 9 Quarry Scale 4 Feet = 1 Inch. * I 1 1 18 Courses Courses Plate 4 x 3 Brick on Edge in Cement Section on Line A.B. lating Joists 3 x Bond 4 × 3 X Paring Published by Atchley & Co 106 Gt Russell Street, London. April 1857. Bracke 2 x 8. ۱۲ 3 York: Step - 26 2 eft x n 1. # -J · Plate 5×4″ 1 I Common Rafters ist Wall plate 4.3 returned all round the Walls 47/2 × 2 Iv ne · " tett 6 x 3 ar ex Ceiling Jousts X Head of Partition 6× 4 spiked to Principal Rafter दिना Ridge 91% Shutt ve Sill 9x7 Yellow Joists Principal Rafters 9x6 Brick Deal 5 × 2 Bench 8×3. Post 4 × 4° Floor Fo o t i n g s Purlins 6x4 x 3 T 29 Courses Coursesx- 39 Courses t Plates 65 to be returned round the Gables bur 4½ Cast Iron Eaves Gutter 40 Courses I PI. 26a [ J.R.Jobbins. 6″ x 6″ 1 1 S t at e 5 ===<# 4 X 2. 6° Plan. 19'. Q." ·2.6^ S la te t J t f I I + 1 Ø ^ 6 U N A L S Elevation R I .2′. 6′ 5' x 4" I 1 Published by Atchley & Co 106 Gt Russell Street, London. April. 1857. = Loxt 5 4 #1 4 x 2 H 11/4 Boarding # 6 X 6 " A+G 4 6′.0" ↓ အများအာ O O Section. Scale 2 Feet 1 Inch 1 + 2'.0" s i a z e "Cox* 5 X 11 4 12" x 4 ก ון =c++ X Pl. 27. C < J.R.Jobbins. Framing of the Arm A B O O Q O O O O O O 10 O O 000000000000 O O 3 O 7 2'. 0 The Zinc Plate is Rivetted to this Framing thaig $ 1 I I ། O! 1 [ 1 1 O O 10 3 O O O O O Onderde O O O O O Elevation. 1 x 27/2 Wear Rod : : Staple ** O Staplę 000000000000 Pin to Stop the Lever 1 dram 8/2 SIGNAL 1/2 2 13¾4 2 12 1½ " 可 ​2 9°¾/4 93/4 Ź 93/4 1/2+ 1 ½ ½ 2 2 × 2 ¾ 4 2 221%2 1 і гипогру Side Elevation C D ㅁ ​¿ Published by Atchley & Co 106 Gt Russell Street, London. April 1857. 1 1 $ Rest Stop Rod #diam? A Section at A H Rod ½ diam 1 1 Section at B. Caution Stop 1 Rod 1/2 diam. Indo ·Danger Stop Ad Post General Drawings Scale 2 feet = 1 Inch Details. Scales full size • -- 7/26 I 0 ! 1 1 Pl. 28. I • 2 I i ¿ Date Due } I 1 Transportation Library TF 200 H37 v.2 Haskoll,W.D. Railway construct- lion 意​! 5 浙 ​1 * 3.1