49) The first shiploads of immigrants bound for the territory which is now the United States crossed the Atlantic more than a hundred years after the 15th- and 16th-century explorations of North America. In the meantime, thriving Spanish colonies had been established in Mexico, the West Indies, and South America. These travelers to North America came in small, unmercifully overcrowded craft. During their six- to twelve-week voyage, they subsisted on barely enough food allotted to them. Many of the ship were lost in storms, many passengers died of disease, and infants rarely survived the journey. Sometimes storms blew the vessels far off their course, and often calm brought unbearably long delay.