| http://www.w3.org/ns/prov#value | - r. ??? ??? ??? John Stevens The first chief engineer in charge of the Panama Canal construction project. ??? ??? ??? oil A thin coat of this over standing water killed emerging mosquitoes. ??? ??? ??? Yellow Fever This disease, along with smallpox and malaria, was a major problem in constructing the Panama Canal. ??? ??? ??? Chagres The river that was dammed to form the re
|
