sanitation and organization the greatest factors Though the actual work in diguing the canal was wonderful, far surpassing anything the sortthat had ever been accomplished before, the work of the United States Government in making the isthmus healthful and in taking care of it's army of laborers was an even greater feat. When the work began, both Panama and Colon were subject to yellow fever, which at times almost paralyzed activities in the region. Since it had been discovered that yellow fever is caused by the bite of a particular kind of mosquito, The Government engineers had a basis upon which to work. The sanitary force, under Dr. W. C.Gorges, installed a system of sewerage in the two cities, caused the streets to be paved and prevented the collection of heaps garbage and stagnant water in which mosquitoes mirth breed. They kept the undergrowth