Despite the Romans' common use of lead pipes, their aqueducts rarely poisoned people. Unlike other parts of the world where lead pipes cause poisoning, the Roman water had so much calcium in it, that a layer of plaque prevented the water contacting the lead itself.
OMB definition, Office of Management and Budget: the division of the Executive Office of the President that prepares and administers the federal budget and improves management in the executive branch. See more.
PTB is an acronym for Power Tab File. Files that contain the .ptb file extension most commonly store music tablatures that are used in the creation of sheet music for stringed instruments such as the bass and guitar. Many of the tablature files that contain the .ptb file suffix are created with the Power Tab Editor tablature authoring software. The Peachtree Corporate Accounting software is also known to use the .ptb file suffix. When a PTB file is associated with the Peachtree software, the file contains backup data files that are used by the application to restore lost or corrupt data.