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ROOSEVELT AND GOVERNMENT CAMP, TO BE SUBMERGED WHEN DAM IS COMPLETED.

information is disclosed that immediately at the proposed dam site occurs excellent material, in unlimited quantities, for the construction of first-class cement, so that the government held a card up its sleeve. In fact, the estimates of the engineers placing the cost of the project at three million dollars was based on the calculation of $3 a barrel for cement, or a difference of $1,200,000. Mr. Davis told me last winter that the cement could likely be made by the government for $2.50 a barrel or less. If the trust had won its fight, the dam and project would have been increased in cost to $4,200,000. There was considerable scurrying about at Washington when the cement people found out where the government stood. They realized that if the government built a cement mill and manufactured its own cement they would not only lose a large order, but that it would be, in a way, establishing a precedent. The government was interfering with private enterprise. The various cement men saw their Representatives and Senators, and had it been simply a question of a saving of government money, the outcome might have been uncertain. But when it became generally known that any increased profit, which went to the cement manufacturers, must be paid by the people and farmers of Arizona, it put a different phase on the subject and the fight was soon over. Under the irrigation act the settlers or water users under any project must pay back every cent expended by the government on the irrigation works.

The Reclamation Service of the Ge

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to make government irrigation not only a success, but to protect the interests of the irrigators, even to a point of raising controversial questions and incurring the hostility of interested parties.

A very recent development wherein the government showed its anxiety to make the irrigation scheme a success and construct works at the cheapest rate possible came to light when Comptroller Tracewell of the Treasury Department disallowed what he termed a railroad rebate, in favor of material transported for irrigation construction. Secretary Hitchcock held that the reduction of the rate was not, as a matter of fact, a rebate, but that the government was entitled to secure the lowest possible rates from the railroad companies, moreover the saving to the government meant, in reality, a saving to the pioneers and settlers, who would take up their little tracts of land under the irrigation projects, since they would have to pay back to the government the cost of the construction, and the cheaper it could be made, the less burden would fall upon them. This difference or so-called rebate will amount, in the transportation of irrigation materials to complete the projects now under way, to

at least a million, if not a million and a half dollars, and it is a matter for congratulation that the Attorney-General upheld the position of Secretary Hitchcock.

This cement venture of Uncle Sam's in Arizona is apparently working out satisfactorily. The work is well under way on the Roosevelt dam, and the government has been busy with preliminary work for over a year-building an expensive rock road from Phoenix to the dam site at a cost of about $100,000, building this cement mill at a cost of $120,000, constructing an expensive

diversion canal and tunnel above the dam site, and generating, at that point, 10,000 horse-power, to be used in running the mill and in furnishing light and power for drilling operations in the tunnels, hoisting materials-in other words, building the dam. So the Salt River will forge its own fetters and construct a gigantic wedge 230 feet high, to create the greatest artificial reservoir in the United States, a lake with a capacity of 1,100,000 acre feet, or the inconceivable number of nearly 350,000,000,000 gallons.

The fuel used in burning cement in the kilns is crude petroleum from the Cali

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fornia oil fields. Some 400 tons of machinery and sixty tons of structural iron were required in building the cement mill, the ball mills weighing about twelve tons each and the tube mills when ready for grinding about twenty tons. The crusher weighs fifteen tons and the rotary kilns for burning the cement are seventy feet long and weigh forty tons each. Attached to the mill is a well-equipped laboratory under the charge of two chemists, who will devote all their time to standardizing the cement materials and testing the products of the mill.

It may be stated that before the cement manufacturers gave up the fight last winter, they dropped down from $9 to $4.81 a barrel. The cement used in the pre

liminary work at the Roosevelt dam site cost $5.35 a barrel delivered at that point. This was reasonable, compared with $9, but Uncle Sam had the bit in his teeth and he proposed to go the limit. The present figures of the government men are only $1.60 a barrel for the cement making, and if the cost of the plant, $120,000, be added to the cost of the 200,000 barrels of cement required, the total cost of the government cement will be only $2.20 a barrel. This means a saving of $2.61 a barrel, even against the low bid of $4.81, or $522,000.

After the dam and canals have been completed, the cement plant will still be capable of further use and considerable salvage can doubtless be realized.

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THE QUARRY, SHOWING NATURAL STRUCTURE OF THE GRANITE AND THE ROUGH

MONOLITHS IN THE FOREGROUND.

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THE practicable limit, in size, of one-piece, granite columns, seems to have been decided by recent experiences in the construction of the new Cathedral of St. John the Divine in New York. This is now rising slowly from its foundations, which consumed so much money and so many years in the laying, over on Morningside Heights. The structure is noteworthy, in that it will be one of the grandest churches in the world when finished. Moreover, there have just been placed in it, eight immense granite columns, which tell a story of pluck, patience, and persistence rarely equalled in granite cutting.

These eight pillars, which are the largest in existence, excepting those of the Cathedral of St. Isaac in St. Petersburg, are six feet in diameter and fifty-four feet high, standing on fifteen-foot pedestals. They are each in two parts, respectively thirty-six and eighteen feet in length. The discovery of the necessity of dividing them in this manner, instead of mak

ing each in one piece, as was originally intended, followed operations which taxed the resources of mechanical science and caused the loss of thousands of dollars.

The pillars were quarried at Vinalhaven, Maine, by the Bodweil Granite Co., being taken from the Wharff quarry, the only one in New England where such immense blocks could be obtained. They weighed three hundred and twenty-five tons when first got out and were eight and a half feet square and sixty-seven feet long.

Granite lies in great natural sheets, the horizontal divisions of which are as plainly visible as the layers of a Washington pie, which they somewhat resemble. These sheets are usually thin near the surface of the ground, but increase in thickness with the depth, so that in opening a quarry it is generally necessary to blast out and remove the superincumbent, shallow strata. In quarrying, there must be a front and two ends clear, and

face

the

the two

feet drilled

free from "salt cracks," faults, and other imperfections. A line of "foot holes," as far back from the of the ledge as the thickness of block desired, is first drilled, holes being eighteen inches to feet deep and three or four apart. In line with these are other holes only three inches deep, called "plugged and feathering" holes. In a plugged and feathering hole are placed two pieces of steel, joined into a spreading socket at the bottom. A wedge is then driven into this socket, all the holes being wedged and driven at once so that a break may be started the line. The foot holes ilarly wedged. If this cleavage were placed too edge it would "run off" along the upper front the block; but when it is placed far enough inward the resistance of the mass of the rock holds back lateral shove of the wedges, thus the ledge's inertia helps split it.

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all along

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line of

near

or

edge

the

split

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and

to

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rollers are dispensed with and the stone is rolled over and over on a bed of cordwood sticks, called "dunnage," which is reduced to splinters by the enormous pressure. Whichever method is adopted requires the use of complicated tackle, often with double and triple purchases, or "luff on luff," as the sailors say.

In getting out the mammoth blocks for the cathedral columns these processes were followed in much the same way they would have been had the piece not been of unusual proportions. It was in the later stages of the work that the greatest difficulty was encountered. The magnitude of the undertaking will be better understood when it is known that these immense masses of stone were to be put in a lathe and turned down to dimensions, exactly the same as if they had been

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THE GREAT PILLAR READY FOR THE TURNING LATHE.

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