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Arbiter 21. Should any difference of opinion arise, either during the construction of the works or subsequent to the completion thereof, regarding any matter connected with the Contract or works which has not been hereinbefore specially precluded, the same shall be submitted to and determined by Mr. Gordon T. Frew, of Messrs. Kyle & Frew, C.E., Glasgow, whom failing an Arbiter to be appointed in terms of the Arbitration (Scotland) Act, 1894, as sole Arbiter, and the decree or decrees, decisions, valuations, and awards of the above-named Arbiter shall be final and binding on all parties, and shall not be subject to review in any court of law.

Schedule of Rates 22. The Rates in the Schedule shall be the total charge for the completion and maintenance of the work, and shall include all risks of every kind, and the providing of all necessary materials, plant, and workmanship, and setting all tobies to proper levels and camber.

The Rates in the Schedulo for removing existing concrete foundation and compressed rock asphalte, and providing and laying concrete foundation, shall include all necessary excavation, and the free maintenance of the whole work for a period of *

.. years.

* To be filled in by Contractor.

If the period of free maintenance be less than ten years, the offerers shall state a rate per square yard per annum for the after maintenance of the entire area for such number of years as shall make the total period of maintenance ten years.

The Rates in the Schedule for the restoration of openings, where disturbed or opened by Corporation Departments, proprietors, or others, shall include everything necessary to make a satisfactory restoration, and particularly all necessary excavation, cutting and trimming edges of asphalte and concrete, providing and laying new concrete and asphalte.

Corporation to Lift Asphalte Paving 23. The present asphalte paving shall be lifted and removed by the Corporation Statute Labor Department.

Excavation 24. When the asphalte paving has been removed the Contractor shall excavate and cart away the existing concrete foundation, and remove all rubbish and surplus material carefully, and prepare the bed to the required levels and camber.

Extra Excavation When the average depth of excavation exceeds the combined depth of asphalte and concrete foundation, the extra quantity will be paid for at Schedule rate for "Extra Excavation."

Foundation 25. The concrete foundation shall be composed of one part Portland cement, one and one-half parts of clean, sharp sand, and four parts of broken whinstone. The parts shall be measured separately, and by bulk, in boxes 3 feet square by 1 foot deep. Only clean, haid stones shall be used for concrete, and they shall be broken to pass through a ring 14 inches diameter, and screened with a 34-inch mesh screen. All the materials which pass through the screen shall be rejected, unless specially permitted by the Master of Works or any person appointed by him.. All the stones shall be made up in heaps, and shall not be used until approved of by the Master of Works or any person appointed by him.

All concrete shall be thoroughly mixed in a close-jointed wooden platform by turning it over twice in a dry state, and twice in a wet, only as much water being used in mixing as to bring the mass to a proper consistency.

All concrete shall be used immediately after mixing, and the Contractor must protect the same until it has properly set. The surface of the concrete, when placed in position, must be perfectly smoo and to required levels and ca

Sand
All the sand used shall be clean, sharp river or pit sand.

26.

Cement 27. The cement shall be of the best quality of British Portland Cement, manufactured on the Thames or Medway, and shall conform in every respect to the British Standard Specification for Portland cement as drawn up by the Engi. neering Standards Committee, as revised and published in August, 1910. A copy of this Specification can be seen at the Office of Public Works, City Chambers.

The Contractor shall state in the Tender the brand of cement to be used on the work, and maker's name, and all cement supplied shall be of the brand stated, and shall be delivered on the work in sealed bags, having the maker's name stamped thereon. The cement, when brought on the ground, shall be properly protected.

Rock Asphalte 28. The rock asphalte shall be new, pure, natural, bituminous rock, of uniform texture, finely ground, and free from all impurities, and shall contain not less than 9 per cent. or more than 13 per cent. of natural bitumen. A sample of the rock asphalte powder shall accompany the Tender, in a sealed bag, having the name of the Contractor and the name of the mine which the sample is taken from stamped thereon, and all powder supplied shall conform to sample submitted.

Laying Rock Asphalte 29. The powder shall be heated in mechanically-driven revolving cylindrical roasters, and when brought on the ground shall be at a temperature of not less than 220 degrees Fahrenheit.

It shall then be spread on the concrete foundation to the proper thickness, and thoroughly and uniformly beaten down and compressed with heated flat-iron beaters to a smooth and uniform surface, and to the proper levels and camber, and, if necessary, rolled with a heavy hand-roller, particular care being taken in laying the powder round tobies, manhole frames, etc., to see that the powder is well rammed and kept flush with the top of such toby, etc. The work shall be carried out by thoroughly experienced workmen under the supervision of a responsible foreman, properly qualified in the laying of compressed rock asphalte.

Immediately after being laid the surface shall be dusted with dry Portland cément.

Fires 30. The fires on the work, used for heating tools in connection with the laying of the asp Ite, shall be fired with coke, and shall be placed in such positions as may from time to time be ordered by the Master of Works or any person appointed by him.

Water 31. The water used shall be pure, and free from all vegetable or putrid matter.

Tobies 32. All tobies shall be set to suit levels and camber, and be built up with brick and cement mortar composed of one part sand to one part cement.

Standing Orders and Instructions to Be Complied with. 33. The Contractor shall comply with all the Standing Orders and Instruc. tions of the Corporation relating to Contracts, particularly those annexed hereto:

CORPORATION STANDING ORDERS AND INSTRUCTIONS RE CONTRACTS

Firms Eligible to Tender (a) Only persons or firms paying the standard rate of wages or piece prices to all competent workers for all classes of work, whether under Contractor otherwise, and recognizing Trades Union conditions, or in districts or places where no standard rate of wages or piece prices or Trades Union conditions exist, paying such wages or piece prices, and recognizing such conditions of labor, as are generally recognized as fair for all classes of work in such districts or places, shall be eligible to offer for and receive Corporation Contracts.

Foreign Manufacturers (b) Any foreign manufacturers, or the agents of foreign manufacturers or merchants, offering to supply any goods or materials to which such Specifications and Schedules refer, shall be bound to send to the Corporation, along with their offers, a written and duly authenticated guarantee, to the effect that the manufactories or works in which goods or materials have been, or will be, made, are carried on in conformity with the provisions of Clause (a) hereof, both as regards payment of wages or piece prices and other conditions of labor.

Wages (c) The Contractor shall pay to all competent work people employed by him not less than the standard rate of wages or piece prices in each branch of the trade, or, where no such standard rate or piece prices exist, such wages or piece prices as are generally recognized as fair in the trade; and in districts or places where the Glasgow scale of wages or piece prices do not apply, shall pay not less than the standard rate of wages or piece prices paid in such districts or places, or, where no such standard rate of wages or piece prices exist, such wages or piece prices as are generally recognized as fair in the trade in such districts or places.

Extras (d) The Contractor shall not receive any payment or consideration for any extra work over the estimated or contract price, unless the extra work has been formally sanctioned by the Committee interested before any part of the extra work is executed.

Offering Gratuity (e) If the Contractor shall be found to have offered or given any gratuity, bonus, discount, or bribe of any sort to any Corporation officer or employee, it shall be competent for the Corporation forthwith to cancel his Contract, and to hold him liable for any loss and damage which the Corporation may thereby sustain.

Wages Paid to Be Entered in Proper Books (f) The Contractor shall, to the satisfaction of the Corporation, provide and keep proper books, in which shall be correctly and promptly entered, from time to time, the names of, the wages paid to, and the hours of labor observed by all work people employed by him in or about the execution of this Contract, and shall, from time to time, when required by notice, in writing, under the hand of the Town-Clerk, produce the said books, or any of them, to him, or any person appointed by him, who shall be at liberty to inspect the said books and take copies thereof or extracts therefrom.

Sub-letting Contract (g) The Contractor shall not assign this Contract or sub-let the same, or make any Sub-Contract with any person or persons for the execution of any portion of the contract (except such works as are in the Specification provided

to be executed by particular tradesmen), without the consent in writing of the Committee interested being first obtained.

Use of Fire-plugs (h) The Contractor shall not for the purpose of this Contract make use of any fire-plug, valve hydrant, or other appliance belonging to the Corporation and under the control of the Glasgow Fire Brigade for the extinction of fires, without the consent, in writing, previously had and obtained of the Chief Officer of the Fire Brigade, and he shall be liable for all loss and damage occasioned, or which may be occasioned, to any such appliances by or consequent on such use thereof.

Insurance of Workmen (i) The Contractor shall insure, until the completion of the work, with a responsible Insurance Company against all claims under the Workmen's Com. pensation Act, 1906, and shall obtain from the Insurance Company an indemnity in favor of the Corporation. He shall produce his policy and indemnity to the Town-Clerk. Should he fail to produce such policy and indemnity or receipt for renewal premium within five days after being called upon to do so, the Corporation may themselves insure against said claims, and charge the premium against the Contractor. Until the policy has been issued, the production of a satisfactory cover note will, in the interim, be accepted for the period of its currency pending the issuing and production of the policy.

Cartage (j) In all Contracts for cartage work entered into by the Corporation the Contractor shall be bound to employ competent workmen only for the work to be performed under his Contract, and shall pay to such workmen a minimum wage of 248. a week.

ASPHALT WORK IN BERLIN

BY INGENIEUR HANS STILLER From the Bulletin of the Permanent International Association of Road Congresses

March, 1914 For the laying of compressed asphalt, Berlin and its suburbs may rightly be regarded as worthy of imitation. The introduction of asphalt has been particularly favored by the level character of the streets, so that, in 1911, in Berlin alone 2,953,718 square yards or 43.8 per cent. of the existing area of carriageways were laid with asphalt. Attention has, in this journal, been repeatedly directed to the fact that the letting out of the asphalt work is a pure matter of confidence, and that only contractors of proved trustworthiness are allowed to compete for it. In Berlin this principle is adhered to in the strictest possible manner.

The City of Berlin has concluded an agreement with nine of the best known asphalt firms, according to which all asphaltings within its precincts, in the meantime till 1917, are made over to them, and by which in all constructions of asphalt roads by private contractors the latter are also required to have the asphalt work done by one of the firms on the list. As a set-off to this, Berlin obtains the asphalt at the low price of $2.50 per square yard when it is laid on an 8-inch foundation of concrete, $0.70 of the rate going to the latter. The price per inch of thickness of the concrete is set down at $0.09. Gravel is used in the manufacture of the concrete, but the use of old concrete crushed to pieces of 2-inch size is allowed up to one-third of the gravel percentage. The mixture is in the proportion of 1 to 8, any required higher percentage of cement being reckoned chiefly in relation to the number of tons of cement used. Internal fittings occupying less than 1 square yard of the pavement are not deducted. When tramway rails are built in, the following allowances are made:

For making the compressed asphalt border against the rails, per yard length of side of rail....

$0.11 For the cast asphalt under the rail (breadth of base 64 inches) { inch in thickness. .44 For each additional | inch of cast material under the rail, per yard of the latter., .11 For filling the cavities at the side of the rail web with cement concrete, per yard of each side of rail...

.04 For filling the cavities between the lower side of the rail-head and the top of the concrete with cast asphalt, per yard of side of rail-head...

.22 New of their kind are the rules relating to the work of the contracting firms in the suburbs. There are 27 suburbs, mentioned by name, in which the contracting firms are not allowed to work more cheaply than in Berlin. In case a firm nevertheless quotes a cheaper price for work in a suburb, it must allow this to rule in Berlin also during the year in question. The same holds good for the maintenance; should a firm agree to a longer term of gratis maintenance than that of the Berlin agreements, this holds for Berlin also, and when the price for the gratis maintenance, which is graded down, per year and square yard from $0.10 to $0.04, is diminished, the same reduction comes into force for Berlin also. This last named provision is of considerable significance, since the maintenance for payment embraces the term of 15 years, whereby it is to be observed that only such streets come in question for this as have been constructed in the same year as the suburban roads in question.

The distribution of the asphalt stretches to be undertaken is made according to the free judgment of the hydraulic engineering administration; special agreements are made for the individual asphaltings, in which the prices for subsidiary operations are laid down and the technical conditions for the paving are contained.

The asphalt firms have to maintain the pavement for four years free of charge, and for the next following 15 years for payment. In connection with an agreement for such a considerable length of time, the provisions of the maintenance agreement are of considerable importance. Since lines of rails are laid in many of the streets, the agreements also extend to the pavement bordering against the rails. In the separate agreements referred to, the maintenance of the permanent way, which, in Berlin, has to be undertaken by the tramway companies, is accordingly made over to the asphalt firms at the same time. The contracting firm, then, enters into agreement not only with the City of Berlin, but also with the tramway company; with the latter, however, only so long as payment of the remuneration agreed upon is regularly and punctually made by them.

The annual rate of payment up till the 19th year is $0.10 per square yard. The tramway company has to pay $0.15 per square yard for the surface within, between, and for 26 inches at each side of the tracks, or for the 18-26 inch strip outside the tracks in case the spaces between rails and tracks are surfaced with a different material and are not laid by the asphalt firm in question. As this is very seldom the case in Berlin, and the permanent way is in most cases laid with asphalt as well, the deciding provision is generally that by which the asphalt firm receives $0.15 per square yard per annum from the tramway company for the pavement of the track. To this has to be added $0.44 per yard per line of rails per annum for the maintenance of the rail bordering. It is stipulated in the agreement that the asphalt carpeting must not show any defective places, cracks, or holes, and that it must everywhere lie closely against the rails, etc., that are imbedded in the pavement, provided these structural parts be firmly fixed. This point has to be decided by the administration.

It is obvious that a clear demarcation of the obligations of the contractor is here hardly possible. For, try as one will, it is often impossible to decide, whether a rail is loose or not. For the municipality, the question is one of minor importance, because the tramway company is, in the first line, bound to attend to the maintenance of the pavement.

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