The bulk of this paper consists of a series of graphs and tables linking radiocarbon dates with corrected dates derived from measurements at the University of Pennsylvania Radiocarbon Laboratory. The time span of AD 1849 to 5383 BC (calendric years) is covered by 631 carbon-14 determinations on samples of wood <i>(Sequoia gigantea and <i>Pinus aristata) independently dated by dendrochronology. These data are treated by a 9-cell regression weighted averaging' technique to remove some of the scatter, and to yield both the calibration graphs and tables that give corrected dates corresponding to radiocarbon dates at ten year intervals. Brief sections of text give an introduction, state the methods and definitions used, give examples and discuss the application and the geophysical implications. -- AATA