Arizona republican., 1911-01-28

rounding mountains. With a full res ervoir these may still increase, but eventually as the years pass by and in the degree that the water carries silt they may be expected to gradually fill up. The quantity of water lost is in finitesimal and they betoken no inse- curity in the construction. The floods will never be big enough to wash away a range of mountains, even if little water does percolate thro~gh. Such phenomena is nearly always noted be- low big dam.
 Another thing may happen, said MT. Davis, that might cause some timid person alarm, but in which there is no danger The Roosevelt dam is now ap- parently is sound as d dollar, not a crack being visible in it. But it will crack some day or remain forever in a class by itself in dam construction. All big dams crack. The CrotOn dam in New York, which is bigger than this one, has cracked in numerous places, but not in a way to cause alarm. This is no reflection on the material used nor on the construction. It is due sole ly to conditions perfectly understood
  have all to be compensated for by added strength in volume of yardage and in numerous other ways, he eX plained, which only an engineer could fully describe. The cracking will probably come sometime as the result of expansion and contraction. The structure is bound to contract in the cold of winter and expand with the heat of summer. The cracks however will not be dangerous, or material or sufficiently large to impair the strength of the dam, so if some tourist should see a little crack some day he need not take fright and flee to the sur rounding hills. A unique method has been devised for lessening the pOssi bility of this expected condition. It is planned if deemed desirable to run a small perforated pipe or similar device across the lower face of the dam through which very small amount of water may be allowed to trickle over the wall during the extreme hot wealth CT, just enough to keep it damp, and the evaporation will aid materially in keeping the dam at a cooler tempera- ture. That is only one of a hundred little engineering details that an ordinary hired man would not think of if he were going to build big dam.
 Mir Davis said there was consider able rain between here and Roosevelt on Wednesday and the roads between Mesa and Sacaton were quite muddy in places yesterday. He rather expected to find Phoenix knee deep in mud but probably did not know that it never gets muddy here since Phoenix resolved to have paved streets.
 The trip to Sacaton was 10 inspect the pumping plant for which the gov ernment is supplying power from Roosevelt. It was not in operation yes terday as everything is now well wet up on the reservation and the water was not needed. It is working all right. however when 1t Is needed. Seven wells are now equipped for iTrigating purposes. There is lots of water in the San Tan canal also.
 On the Roosevelt trip the party made i detour to Granite Reef and found working finely. It was rath- sr a pleasing sight to see a foot of water dropping over the big thousand loot long dam, due to another little rise In the Verde. The hills between Mesa and Roosevelt, says MT. Davis, look yreener just now than he Q. CT saw .hem before.
 MT. Davis was asked if he would be lere on the occasion of the formal dedication of the dam in March by Theodore Roosevelt. He said he could lot tell at this time. He may be here put he has made no plans to that end ret.