strap over the forehead. One American contractor who was new to construction work in Mexico shipped in a carload of wheelbarrows and the peons obligingly tried to use them by carrying them on their heads, but that is another tale. The wheelbarrows went back to the States and the thousands of tons of dirt and rock shifted about in the Necaxa work have been moved in baskets. This is an improvement over some parts of the Republic where peons in similar work carry the dirt in gunny sack aprons.

In the accomplishment of this work it is to be doubted if the famed engineers of Panama have been called upon to solve any more perplexing problems. The project would not be an easy one with a level piece of ground on which to construct a power house and with railway lines and machine shops located conveniently. Here they had none of these advantages and the impossible has been accomplished so often in the course of the work that you cease to marvel at it before you have spent an hour at the plant.

In the first place it was necessary to construct a railway

line from Carmen, the terminus of the Hidalgo road. This narrow gauge road, by pursuing a devious course through valleys marked by this frowning Sierra Madre Mountains managed to reach Carmen, but at that point it was thought further construction was impossible and the problem of transportation was turned over to the burros. Obviously it was impossible to transport huge dynamos, lathes and mile after mile of seven foot water pipe over the mountains on the backs of burros, despite the skill with which these animals are packed and the remarkable weights their sagging backs endure.

The construction of the Necaxa railway was begun and completed over twenty-eight kilometers of roadbed so crooked that coupling bars eight feet long are necessary to allow the cars to turn the sharp corners. On this line they will tell you of the careless fireman

THE POWER HOUSE.

who while shoveling coal into the engine one day was startled at the sound of falling glass and looked to see that he had thrown a shovel full of coal into the headlight of the engine. I do not know that the story is true but after a trip on the cowcatcher of the engine-and we really caught a calf that day -I can testify to the fact that the average summer park scenic railway looks like a Harlem streetcar line in comparison. People from all over the world who want to build a crooked railroad come to look at this one, and then go home satisfied that their own job is an easy one. The road wanders along the edges of cliffs and over the spinal columns of razor back mountains so lean that a cigarette tossed to the right or the left would fall in a

reservoir of the system located. Promontories of two huge mountains approach each other here, enclosing a valley which some believe was once a huge natural lake. If it was, it existed many centuries ago for in it were many farms which the promoters of the Necaxa enterprise were compelled to buy from Indian owners who traced their titles back to the time they bought it from the Spanish conguistadores who had previously stolen it from their ancestors.

The town of Necaxa was bought and moved to higher ground and now all that remains to be seen of it is the tower of what is said to be a picturesque old Spanish church, replaced by one of modern concrete construction high on the hill. When the dam is finally completed this too will disappear under the higher level of the water.

The big dam forms the Necaxa reser

two years of continued drought. Tunnels through the mountains connect all of these reservoirs which lie in parallel valleys.

The Necaxa dam is 194 feet high, about 1300 feet wide at the river bed and contains almost two million cubic yards of material. The dam is built of stone and concrete as to both upper and lower toes and the center is composed of stone and clay sluiced in from the hills which rise high on each side. Two giant monitors, working night and day, fed by water from auxiliary reservoirs high up on the plateau, filled the center of the dam, and the water from the sluices drained back into the reservoir.

At this point the railway ends, for, resourceful as we are, no American engineer has as yet been able to construct a railway which will make a descent of 1400 feet in one mile. A quarter of a.

mile below the big dam is the first Necaxa fall, or rather the precipice over which the water formerly fell, for so well have the engineers secured every possible drop of water that only a little stream trickles over and disappears into the vapor before it reaches the old river bed 460 feet below. A short distance from the first fall is the second fall, 740 feet high and below it is the power house, 1400 feet lower than the water level in the reservoir. Over the edge of these two falls all the machinery used in the power house has been lowered by means of a pair of elevators, strong enough to lower a locomotive engine without straining the machinery. Visitors to the. power house are now taken down on these elevators and nearsighted ones are unable, when near the bottom, to see the upper end of the cable which appears to vanish into the air, like the magic rope up which the Indian jugglers climb into the sky.

A more rapid means of locomotion has been provided by means of a tunnel,

which penetrates the mountain at an angle of about forty-five degrees and through which a passenger car thirty inches shallow is pulled on the end of a cable. By lying on your stomach at the bottom of the car the trip can be made in safety and comparative comfort, though care should be taken that the man who is piled on top of you disposes of his angies in a manner best suited to your own comfort.

Over the old bed of the river the power house has been constructed with as much care to detail and appearance as if it were a New York showplace instead of an enterprise located so far from the track of tourists that the names of the visitors of a year can be recorded in a very thin book. The power units, I am told, are the largest ever made and new records are being set in the construction of additional machinery. Water is carried to the turbines by means of pipes which pierce the mountain, bringing to each turbine a stream of water six feet in diameter and carrying all the force of

a drop of 1,400 feet. The power is developed at a voltage of 4,000

which is raised to the line pressure of 60.000 volts by means of five banks of 2,000 kilowatt single phase transformers. This current with the voltage of a playful bolt of lightning is carried to the Valley of Mexico over wires strung on steel towers. Inside the valley of Nonoalco the voltage is reduced to 20,000 and again to 3,000 for distribution around the city in underground conduits.

As has been true of many other large power projects, the demand for power from this plant has grown as fast as the plant could be enlarged. The construction has occupied seven very busy years and is not yet completed, though enough power is now being developed to supply all the needs of a population of more than half a million. At first it was planned to develop 50,000 horse-power but it was soon seen that this would be inadequate. Before the original powerhouse was completed it was necessary to

change the plans and provide for one much larger than was originally intended. Now it provides for 250,000 horse-power, and crafty engineers have a plan whereby the capacity may be duplicated by the establishment of another power plant down the mountain side where water which has once turned the turbine will be made to do so again.

As an economic achievement for Mexico the project has accomplished wonderful results. It has cut the price of power in two several times until now electric lights are no longer a luxury in Mexico but an every night convenience. Electric power there is now so low that it competes with human power in the land where human labor is cheaper than any other place in the world. It has made possible the establishment of many manufacturing enterprises and developed a spirit of home industry in a city which has been accustomed to buying all of its manufactured goods from Europe and America. Without it these factories would be an impossibility, for coal in