The first and greatest problem attempted by the United States was to make the Canal Zone healthful. This strip of land from ocean to ocean abounded in disease-breeding swamps and filthy habitations unfit for human beings. The death-rate was appalling and the labor conditions terrible. During the first two and a half years, therefore, all energies were devoted to ridding the Isthmus of disease by sanitation, to recruiting and organizing a working force and providing for it suitable houses, hotels, messes, kitchens and an adequate food supply. This work included clearing lands, draining and filling pools and swamps for the extermination of the mosquito, the establishment of hospitals for the care of the sick and injured and the building of suitable quarantine quarters. Municipal improvements were undertaken in Panama and Colon and the various settlements in the Canal Zone, such as the construction of reservoirs, pavements and a system of modern roads. Over 2,000 buildings were constructed besides the remodeling of 1,500 buildings turned over by the French company. [Illustration: LOCK GATE OPERATING MACHINERY _Photograph, Underwood & Underwood, N. Y._ The great gear wheel, known as a “bull wheel,” is connected with one leaf of the gate on the right by means of a strut so that revolving the bull wheel by means of an electric motor through a train of gears results in opening or closing the gate.] [Illustration: PANAMA, PAST AND PRESENT Scene showing the repaving of one of Panama’s old muddy streets with vitrified brick. Sewers and water pipes were laid throughout the city, resulting in a great reduction of disease.] It was only after all this preliminary sanitation was accomplished that the real work of digging the canal could go forward with any hope of success. These hygienic conditions had the result of making the Canal Zone one of the most healthful spots in the world, and work on the canal became so popular that it was no longer necessary to enlist recruits from the West Indies, the good pay, fair treatment and excellent living conditions bringing thousands of laborers from Spain and Italy. The greatest number employed at any one time was 45,000, of which 5,000 were American. A Battle Won. The completion of this herculean task marked an epoch in the history of the world. A gigantic battle against floods and torrents, pestilence and swamps, tropical rivers, jungles and rock-ribbed mountains had been fought--and won! Well worthy a place in the halls of immortal fame are the names of the thousands of sturdy sons who, with ingenuity, pluck and perseverance never before equaled, succeeded in making a pathway for the nations of the world from ocean to ocean.