tions, and experience would lead to the conviction that with an art subject to such varying development a specific price for specific performance would always be better. In this instance Mr. W. W. Freeman, vice-president of the company, said: "It is true that there is a difference of opinion as to the reasonable interpretation of the franchise provisions as they apply to new lighting developments not contemplated or even imagined at the time the franchise was granted. The maximum amount of such free lighting under the most extreme interpretation favorable to the city would amount, at the present time, to approximately $12,000 annually. Whereas, under the interpretation that the Edison company believes to be reasonable, which it believes the courts will sustain, the amount would not exceed $3,600 at present and would be less for each previous year. The amount of free lighting that has been furnished to date under previous designations approximates $2,000 annually.

"It is doubtful, furthermore, whether the failure of the city to designate additional free lights has involved any actual loss to the city, inasmuch as it is claimed that all amounts paid as franchise taxes or assessments are proper deductions from the amount of tax paid under the assessments of the company's franchise by the State Board of Tax Assessors, which for the year 1906 exceeds $7,000,000. If this view is sustained, as the company believes it will be, the net payment to the city would not be altered by the amount of free lighting, as the value of whatever the company supplies in free lighting would be deducted from what it would otherwise pay in the form of its franchise tax.

"While on the subject of taxation, it may not be amiss to remark that for every dollar paid by the company in dividends to its stockholders during the past seven years, the sum of 60 cents has been paid by the company to the city in taxes, which means that without investing a dollar the city has stood in the relation of a stockholder owning 37.5 per cent of the stock of the company and receiving dividends thereon. The appreciation of this is all that is necessary to acquit the Edison company of any possible charge of failure to pay its full burden of taxation or a fair and full return for its franchise rights."

The views here set forth have broadly sustained judicial approval and acceptance.

A further aspect of the rate and regulation problem was afforded during the year by the Colorado Springs case, which embodied many points of general importance. The historical facts are briefly these. In 1898 the city was being lighted by the Colorado Springs Electric Lighting Company, the lamps being the regular 9.6-ampere arcs. But a franchise was at that time granted for the use of the city water system for power purposes, the considerations including certain hydraulic work for the water system and "lights of standard 2000 candlepower." After 25 years the plant was to revert to the city. But action under this franchise being delayed, the Colorado Springs Electric Company continued to give service as ad interim contractor. In 1901 this company changed its system to the 6.6-ampere alternating-current enclosed arc with a substantial reduction in price to about $80 per year. Meantime the Jackson franchise came into the possession of the Pike's Peak Hydro-Electric Company, but, instead of building a system as was expected, that company built its plant and put in its 6600-volt line entirely off city property and then made a contract with the Colorado Springs Electric Company to take over its output at about 0.6 cent per kilowatt-hour and to assume the work of lighting the city in fact, although in law the work was being performed by, and the bills were paid to, the Pike's Peak company. A suit followed, the city alleging that the Pike's Peak company was avoiding its obligations regarding establishing a system, which suit the electric company won on the ground that it was free to employ an agent. Service was continued on city lamps as before, and a series of disputes followed, partly with respect to the use of the water and later as regards the quality of the lights. These particular lamps had not been formally accepted by the city, which in all documents reserved to itself its rights under the Jackson franchise, but service had gone on and had been increased with the existing 6.6-ampere alternating arcs. Meanwhile the Pike's Peak company and the Colorado Springs company had fallen under virtually the same ownership.

Finally, the city demanded that the lights required by the Jackson franchise be furnished and damages for the deficit in light be paid. After long discussion, an agreement of arbitration was signed, which in terms specified that any deficit of the

service given should be measured in candle-power. Under the Colorado statutes, a board of arbitration has large power, is judge of both the law and the facts, and, on the issues stipulated, its decision is practically final. Such a board was constituted and began its hearings early this year.

The one technical point on which all the experts in their testimony fully agreed was that the regular 6.6-ampere alternating arc taking about 400 watts at the arc and about 427 at the lamp terminals was not a proper substitute for the lamp of the franchise under any definition. The contention of the city was that the standard 2000-cp lamp of 1898 was the 9.6-ampere open arc consuming about 48 volts or 450 mean watts, the enclosed series systems being then only in tentative use and not customarily rated in candle-power at all, but specified as what they were. The defence, without denying that this was the usual lamp of the period, took the attitude that under the National Electric Light Association resolutions of 1894, any lamp, whatever the amount or kind of current, which consumed at the arc 450 watts, was a 2000-cp arc within the meaning of the Jackson franchise. The experts for the city denied this purport of the resolution considering the date of its making, and its validity in establishing standard nomenclature in face of the facts in any case. Obviously the watt rating if it were established would lead first to the conclusion that the service since August last met the terms of the franchise, and second, that for failure of previous service the Pike's Peak company could be liable only for the deficit in watts in a comparatively small sum. The experts for the city held that, under the agreement of arbitration, any failure of service should be reckoned on the deficit of effective light, on the basis of maximum mean spherical or other candle-power as the board should determine, but in no case in watts, candlepower not being proportional to watts save in a narrow range and in one kind of lamp. This led to a difference over arc photometry in which the two groups of experts failed to come to any substantial agreement. The experts for the Pike's Peak company insisted that a 7-ampere lamp at 450 watts was the full equivalent of the lamp of the franchise, while those for the city held that it was not.

The decision of the arbitrators, Messrs. H. Floy, E. L. Elliott and Professor L. G. Carpenter, handed down in April, was to the effect that the 6.6-ampere series alternating lamp did not meet the requirements and definition by 20 per cent, in dollars and cents valuation; and a verdict was so rendered, for a portion of the time. For an earlier period of service, when the city had tacitly accepted lighting on the same basis, thus dividing responsibility, the arbitrators halved the alleged damages.

This decision may go far toward settling the question of the rating of the 6.6-ampere alternating-current series arc as a street illuminant. This arc has been, and still is, rated variously in nominal candle-power. It has been called 1200-cp, and sometimes 2000-cp, when substituted for both "half arcs" and "full arcs" of the older type, and more commonly has not been rated in candle-power at all, but sold for just what it is. The decision. implies that even at 450 watts at the terminals the alternatingcurrent lamp fails of being a "full arc" by something like 20 per cent. This corresponds in a general way with the impression among station managers that if alternating-current arcs are to be substituted on even terms for the old "full arcs," the 7.5-ampere alternating-current lamp should be used to retain anything like equivalent lighting. Questions of equivalency in street lighting are very puzzling and will become more so as the luminous arc passes into general use.

VARIATION OF STREET-LIGHTING METHODS

In general, street-lighting methods have remained the same during the year, although the combination of the series luminous arc with the mercury rectifier, noted in last year's report, appears to have ceased to be a novelty by finding its way into ordinary practice. The maintenance of such lamp is said to be quite small. The upper electrode, consisting of a bar of hard-drawn copper supported by iron wings, burns at a comparatively low temperature, resulting in an average life of about 4500 hours. The lower electrode, of special compound, in a tube of iron, has a burning life of 150 to 175 hours; so that one man can do much more trimming than is possible with the usual open or enclosed-arc lamp. The renewal of only one electrode also involves greater economy.

Progressive Denver affords one or two examples of interesting advance. The new lighting on Sixteenth street, one of the

business thoroughfares, has involved the displacement of the old arcs and the substitution of 98 new posts of simple and solid design at a cost of about $16,000. The interesting feature is that on these are placed also the trolley wires, so that as both trolley and telephone poles have disappeared the street has a remarkably improved look. Other thoroughfares are being treated in similar fashion.

Denver has, moreover, set an excellent example with its "Welcome" arch. The arch is made after a design chosen from a number entered in a competition, and is that of a Denver resident. It is entirely a home product in construction, and the ironworks that obtained the contract found it necessary to make extensive additions to its plant in order to carry out the scheme. The arch is of cast iron, and is anchored deep in a bed of concrete. All the ironwork is duplex plated, giving it an antique appearance. Including the word "Welcome," which is permanent, there are 1325 4-cp lamps. A changeable electric sign, on which will be placed the name or initials of any organization that may be holding a convention, requires a varying number of lamps. Only incandescent lamps are used, with special colored lamps for particular occasions.

Both sides of the arch are completely outlined, including the scrollwork. All feed-wires are in conduits, and wherever possible the wiring is concealed in holes left in the ironwork in casting. On the leaves and other ornamental portions lead cable is used for the wiring, practically concealing it.

The "Welcome Arch," which stands at the Union Depot in Denver, was dedicated before 10,000 people on July 4. The mayor accepted the arch on behalf of the city in a speech that emphasized the value of light as a welcome to strangers. The arch weighs 70 tons, is 60 feet high, and the driveway is 34 feet wide. The cost of the arch was $22,000, which was raised by public subscription. It will be noted that a small unit lamp is found sufficiently effective, and, indeed, best for the purpose, so that the consumption of electrical energy is kept down to a very economical point.

The arch idea, whether embodied temporarily or permanently, would seem to lend itself admirably to the educational work of a central-station company in exemplifying the value and