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sions of the two end sections. The fol- two in this case gives 1116.5 cubic yards, lowing example will serve to illustrate which agrees almost exactly with that the different methods mentioned.
obtained by the prismoidal formulaThe easiest way to calculate the area this merely accidental, owing, perhaps, of a cross section, whose dimensions are to the similarity of the sections. On given, as in Figs. 4, 5 and 6, Plate I., is uneven ground cross sections ought not to add together twice the center depth to be taken far enough apart to make
and the depth at each side of the road the area of one more than double that
to the quotient the area first found. By' tion book, cross-section sheets and reso doing there will result in this case, turn sheets. On the profile the final A=479 sq. ft, B=147 sq. ft., and M= gradients should be drawn in red and the 291.5 sq. ft. (from diagram). By the surface of the ground in black. It rule first given, M would equal 295.4 sq. should be completed by drawing black ft., which shows how closely the two vertical lines at every 100 feet, on which methods agree.
should be written in black figures the
height of the surface of the ground By mcan depth,. V=1072 cubic yards.
above datum, as ascertained by the By end areas, V=1159 By prismoidal for
levels taken on the plugs; immediately mula, Ist case.... V=1116
above these should be placed the formaBy prismoidal for
tion level in red figures; the height of mula, 2d case.... V-1106
fills should be placed below the surface The method of end areas always gives heights, and the depth of cuts above foran excess, and the method of mean mation level. Cuts and fills should be depths a deficiency. An average of the written in black figures having been as
certained by subtracting surface and according to what is to be written in formation levels, the one from the other. them, should contain the following quanAt each change of gradient, the vertical tities (with others if need be), though lines should be in red and the height of not necessarily in the exact order here formation level written in the same given: Stations from and to, clearing, color, but with larger figures than at close cutting, grubbing, line cutting, side the intermediate stations. Where side ditches, borrow pits, off-takes, catchditches occur they should be indicated water drains, rip-raps, masonry, stone by blue lines at the level of their bot- drains, pole drains, piles, lumber, ties, toms, and the center depth of cutting timber and totals. The divisions, line should be marked in blue figures on the cutting, side ditches, and off-takes should black vertical lines. At the bottom of each be subdivided into three columns the profile should be shown, in blue, the for earth, loose rock, and solid rock, borcurves in the line, with the stations row pits and catch-water drains into two where they begin and end, as well as each, for earth and loose rock; piles into their degrees of curvature; and at the two, for amount delivered and amount top should be indicated the quality of driven, and the timber into as many as the timber and ground, stream and road there are different sizes used on the crossings, culverts, etc. In preparing work. Grubbing, close cutting and plans, all existing objects, as roads, build- clearing are measured by the acre; earth, ings, fences, etc., should be drawn in loose rock, solid rock, rip-raps and mablack lines; water should be indicated sonry by the cubic yard; stone drains, by a blue tint; and works to be construc- pole drains, piles and timber by the ted, as deviations of roads and streams, linear foot; ties by number, and lumber also the center line of the railway and by board measure. Before making out the limits of land required for railway the first return sheet, the line should be purposes should be shown in red lines.
divided into groups so that the cuts and The section book should be filled up fills will come in separate divisions. For so that it will form a complete and accu- instance, if the chainage of one end of rate record of all the longitudinal and a cutting were 1628 +43 and the begin. transverse measurements and levels. In ning of the next were 1640 +64, the di. the upper portion of each page should vision, which would be for a fill, would be entered, in the proper place, the be made from the first mentioned chainchainage to every station and intermedi- age to the last, and the quantities reate point on the center line, each change corded would appear in the columns of gradient, with its rate of inclination, marked side ditches, off-takes and perthe height of surface as well as forma- haps borrow pits. If the chainage at tion level at each station and intermedi- the end of second cutting were 1648+ ate point, and the corresponding depth 20, the division would include all beof cutting or filling. The lower part of tween station 1640 +64 and that station, the
page should have every cross section and the quantities recorded would apregularly entered, giving the distances pear in the columns of line cutting and on each side of the center line, and the catch-water drains. When some of the height above or depth below formation divisions would thus be rendered too level; the slope stakes should also be long for convenience in keeping the acdesignated. Tables of bench marks and counts, it will be necessary to subdivide reference hubs should be made at the them, taking, if practicable, the chainbeginning of the section book, Cross age of some natural or artificial feature sections are plotted on paper ruled for of the ground, such as a stream, or a culthe purpose into squares, each square vert opening as the point of division. representing one foot; their dimensions The column for totals should be divided and areas should be marked thereon. into three parts, for earth, loose rock, The return sheets, which are large, and solid rock. It is filled by adding up should be ruled horizontally and verti- the quantities of each kind of material cally, and on them should be kept an in each horizontal line, and entering the account up to date of all material moved sum on that line in its proper place. Afor used on the section. The vertical ter all the columns are filled, add them columns, which are of varying width! up vertically and place the sums so ob
tained on a horizontal line below the col- should be placed on the road bed but
you may sometime go into contracting, I
labor, etc. The usual form of tender After the grading has been completed indicates the probable amount of each and the ties have been distributed, the kind of material, and the bids are based engineer re-locates the line on the grade on these quantities. Now, if the person very exactly, using a thin picket and driv- bidding feels positive that any of these ing thin stakes (lathes turned edgeways quantities are in excess, and any others will do) at every hundred feet. He also in reduction, he can, by bidding low on drives very accurately grade plugs near the former and high on the latter, keep the stations to the height of the rails. down the sum total of his tender, and
To ballast the line the ties are laid and yet, if it be accepted, run a good chance the rails spiked to them, so that the train of making a reasonable percentage. On can be run slowly over the road for the large contracts it pays to send an expert purpose of distributing the ballast. In over the line so as to ascertain pretty unloading, the train must be kept work- definitely how to bid. Care should be ing to and fro so as to thoroughly mix taken in purchasing supplies, plant etc., the different qualities of ballast, until a for the work; a great deal of money can sufficient quantity is deposited for the be saved by knowing how and when to first lift. The track must then be raised buy. Attention should be paid to the so that there will be an average depth of transportation of supplies, getting them six inches beneath the sleepers, and the insufficient quantity when the rates are ballast must be well beaten and packed low, so as to tide over the time when under and around them. . As the raising they will have risen. It does not often proceeds the end of the lift should ex- pay to sub-let a cutting, owing to the tend over not less than three rail lengths, expense of working it; if any one can and before trains are allowed to pass make anything out of a cutting the conover the inclined portion of the track, it tractor himself ought to be able to do must be made sufficiently solid to pre- it. But in regard to ditch work it is an vent bending of the rails, or twisting entirely another affair. Men are unwillthe rail joints. A second lift is after- ing, as a general rule, to undertake such wards put on in the same manner. In wet disagreeable employment as ditching, cuttings an increased thickness of ballast unless they see a good chance of earning is often necessary. The surface of balo big wages. A grader will take out last pits should be stripped of soil where nearly twice the quantity of material such exists, and no material whatever per diem when working for himself, as
when he is paid by the day; so it is on those of the engineer as to pay the worth while for a contractor to sub-let workmen by, and to enable you to see swamp work to gangs of four or five, in the cost of all the different portions of which case it is well to make a written work. agreement with the men, binding them It is customary for contractors to keep to do good work and to finish within a a store for the purpose of supplying the certain time. To insure the completion workmen with everything they need for of the job, hoid back ten per cent. of the work. If not carefully watched, they their pay until they finish everything are liable to overrun their account, and, satisfactorily. Never pay by bank as they express it, to "jump the job.” measurement, for the navvies will be When sub-letting a piece of work consure to fill up the bank with logs and taining loose rock, it is better to bargain stumps.
A common trick of theirs, es- for a lump price than to pay so much pecially in winter when there is snow on for one kind of material and so much the ground, is to pile about six inches of more for another, because an ignorant moss along the edges of the ditches so man is never satisfied with his measurethat when the measurements are made ments, in any case, and naturally counts with a tape and rod, the depths will be upon a larger percentage of rock than in excess. In working wet cuttings it is he is likely to get. often necessary to corduroy the road bed, Nɔ matter how scarce workmen may both in the cutting itself and on the be, it is always good policy to discharge dump, to prevent the carts from sinking a mutinous man; it keeps the rest upon axle deep in the clay. If the engineer their good behavior. All the men on is a good-natured fellow, he will allow the work should be cautioned against the ties to be used for the purpose. It removing any stakes, benches, or other does them very little harm, and saves a landmarks of the engineer. great deal of expense.
It is necessary, on a contract of any The best way to take out loose rock is size, to keep plenty of plant on hand, by means of sledges. They can be made especially such small articles as nails, very cheaply by taking two of the bar iron, horseshoes, picks, shovels, irons spreading roots of a large tree and brac- for carts, etc. On this point I can speak ing them across; no artificial joint, un- from experience; for once, when in temless it were an expensive one, could porary charge of a five mile contract, I stand the stress that comes the had to make a journey of one hundred pointed end of the sledge. It is often and forty miles, half of the distance on the cheapest way to take out the gullet foot through the swamp' in order to of the cut first: in which case it is advis- purchase a few horseshoes, nails and able to allow a slope ratio of one hori- axle irons; and had to have them packed zontal to four vertical, so that if rock be thirty miles over the line. They were struck there will be no difficulty in giv- pretty expensive by the time they ing it the proper slope. Contractors reached their destination. In contractsometimes find it to be economical to ing, as in everything else, it is better to waste the materials from cuttings where do work well in the first place. One the haul is a long one and the allowance loses in reputation more than he saves in for extra haul is insufficient to cover the pocket by doing scrimp work, besides, in extra expense. Loose rock is often hauled the end, he may have to expend far more to the mouth of a cut and there wasted, for repairs than it would have cost in the contractor replacing it at his own the first place to have completed every: expense by an equal amount of earth. thing according to the terms of the conRock cuts should be kept to the full tract. width and depth as the work progresses, for it is very expensive taking up bot MM. Grimaux and Adam have recenttom. Ties should be cut and hauled in ly accomplished the synthesis of citric winter. It is to the mutual interest of acid from glycerine, and Kekulé ancontractor and engineer to keep liquor nounces that he has been working for sellers away from the line.
the same object, but on different lines. In contracting, make your own meas- He cannot tell at present whether he urements, not so much to keep a check has been successful.
SANITARY ADMINISTRATION IN PARIS.
From “The Architect."
A REPORT has been presented to the The municipality pays nothing for water Public Works Committee of Birming- used for public service. ham by Mr. Till, the Borough Surveyor, Gas.- This does not belong to the describing his visit to the principal Con- city. It is the property of a company tinental towns.
says that in Paris known as the “Company for Lighting every possible opportunity was given to and Heating by Gas." The charge for him for the inspection of the municipal public lamps varies with the burner works. The following are Mr. Till's used. Of these there are three sizes, notes on the water supply, gas, paving, consuming respectively 100, 140, and 200 and sewage of Paris:
liters the hour. The charge to the city Water Supply.—Until 1860 all water is, taking these in the same order, and was supplied by the water company per hundred hours, 18. 3d., 18. 8d. and (Compagnie Générale des Eaux). In the 28. 6d. respectively. If supplied by meter year 1860 the City Council bought up the cost is 38. 104d per 1000 cubic feet. all the company's rights and assets for The private consumers may agree for so an annuity, during fifty years, of £46,400, much per hour per burner, or may use payable quarterly. At the same time an approved meter. In this case the the said company was constituted the maximum price permitted by law is 78. administrative agent of the municipality 9d. per 1,000 cubic feet, being double for all matters relating to the future wa
what the city pays. The same applies ter supply. The company receives in to gas for heating or for gas engines. this capacity a commission fixed thus: The illuminating power is fixed thus: On all annual receipts between £144,000 Under a pressure of 3 millimeters, gas and £240,000, 25 per cent.; between burning at the rate of 115 liters per hour £240,000 and £400,000, 20 per cent.; be. shall give a light equal to the light of tween £400,000 and £480,000, 10 per a (arcel lamp burning per hour 42 cent.; on all over £480,000, 5 per cent. grammes of pure colza cil(3 millimeters, A long and careful inquiry by a special 0.12 inch). Where private consumers commission has just been completed, and use meters they pay rent to the company. their report presented. The main recom- The city does not pay rent for meters mendation in the report is that private registering gas used in lighting streets, consumers shall have meters, and pay but it does pay rent for those used in according to the quantity of water used. municipal buildings of all kinds. The The present system of special contracts gas company may demand monthly payaccording to rent of house is found to ment in advance. The company is not be unsatisfactory and exceedingly waste allowed to demand any other guarantee ful. The water supplied to the city is of from the public. Recently a new mode two qualities; the best comes from the of showing house numbers at night has Seine above the city, from the Vanne, been adopted. An upright frame in the the Dhuys, and from the wells, the sup- form of a triangular prism, eight inches ply from the latter being about 30 per long, is fixed against the wall over the cent. of the total daily supply. The door. On each of the two visible sides Seine and other river water is not filtered is a plate of dark-blue glass, having the before being delivered. The tempera- number in white letters. Inside the prism ture of the well water is 39° F. The is a small gas jet. The first cost of this second quality is from the Marnc and the apparatus is £4, including fixing, and the canals. This is used for washing and cost of the gas about 22s. per annum. watering the streets, and for industrial Streets.-Of the whole city street area purposes generally, but not for cooking 73 per cent. is paved, 22 per cent. being or drinking. It is intended to largely macadamised, and 3 per cent. asphalted. increase the supply of this quality of It is intended to pave all streets where the water, mainly for sanitary purposes. Itraffic is heavy. The dimensions of pav