1. “The Provo Meeting House,” Millennial Star 29, October 19, 1867, 661.

2. J. Milsom, Field Geophysics, 3d ed. (Chichester, West Sussex, England: Wiley, 2003), 169.

3. Once a relatively shallow target, such as a buried stone foundation, is located on a GPR image, it is common practice to dig a small test pit exposing the target in order to compare its depth with its measured travel time to and from the antenna. This allows the geophysicist to readily compute the velocity of electromagnetic radiation, as well as the “dielectric constant” (an electrical property related to reflectivity) for the ground medium between the top of the target and the ground surface. For the test pit dug over the southwestern corner of the first tabernacle foundation, a depth below ground surface of 16 in. (40.6 cm) was observed. When we compare this depth with an observed travel time of 8–10 ns, we can obtain the velocity of radiation in the medium by dividing depth by time (remembering to divide the “round-trip” travel time by two) and then obtain the dielectric constant from the simple formula: V_m = c/√ε, where V_m is the speed of the radiation in the medium, c is the speed of light in a vacuum, and ε is the dielectric constant. This exercise provides a V_m ≈ 0.3 ft./ns (0.09 m/ns) and ε ≈ 11, values typical for moist silty soils. Assuming that the ground conditions do not vary significantly across the survey area, we can now convert all GPR travel time observations to depth below ground surface. For further background information on GPR fundamentals, see A. P. Annan, “Electromagnetic Principles of Ground-Penetrating Radar,” in Ground Penetrating Radar Theory and Applications, ed. H. M. Jol (Amsterdam: Elsevier Science, 2009), 4–40.

4. Lawrence B. Conyers, Ground-Penetrating Radar for Archaeology, Geophysical Methods for Archaeology Series (Walnut Creek, Calif.: AltaMira Press, 2004), 149–59.

5. D. W. Parry, D. V. Arnold, D. G. Long, and S. R. Woodward, “New Technological Advances: DNA, Electronic Databases, and Imaging Radar,” in The Dead Sea Scrolls after Fifty Years, vol. 1, ed. P. W. Flint and J. C. Vanderkam (Leiden: Brill, 1998), 496–516; J. H. McBride, R. W. Keach III, R. T. Macfarlane, G. F. De Simone, C. Scarpati, D. J. Johnson, J. R. Yaede, G. S. Macfarlane, and R. W. R. Weight, “Subsurface Visualization Using Ground-Penetrating Radar for Archaeological Site Preparation on the Northern Slope of Somma-Vesuvius: A Roman Site, Pollena Trocchia, Italy,” Il Quaternario (Italian Journal of Quaternary Science) 22, no. 1 (2009): 39–52; K. M. Stuart and D. G. Long, “Tracking Large Tabular Icebergs Using the SeaWinds Ku-band Microwave Scatterometer,” Deep-Sea Research Part II 58 (2011): 1285–1300, doi:10.1016/j.dsr2.2010.11.004; F. Saïd and D. G. Long, “Effectiveness of QuikSCAT’s Ultra-High Resolution Images in Determining Tropical Cyclone Eye Location,” Proceedings of the International Geoscience and Remote Sensing Symposium 1 (2008): 351–54; J. H. McBride, S. B. Rupper, S. M. Ritter, D. G. Tingey, A. M. Quick, A. P. McKean, and N. B. Jones, “Results of an Experimental Radar Survey on the Gornergletscher Glacier System (Zwillingsgletscher), Valais, Switzerland,” Proceedings of 2010 13th International Conference on Ground Penetrating Radar (2010): 1–6, doi:10.1109/ICGPR.2010.5550157; and J. H. McBride, W. S. Guthrie, D. L. Faust, and S. T. Nelson, “A Structural Study of Thermal Tufas Using Ground-Penetrating Radar,” Journal of Applied Geophysics (2012): doi:10.1016/j.jappgeo.2011.09.011.

6. C. L. Richard, B. C. Pykles, and J. H. McBride, “Applicability of Ground Penetrating Radar and Geographic Information Systems for Documenting and Visualizing Historic Mormon Nauvoo, Illinois,” paper presented at Annual Meeting of the Society for Historical Archaeology, 2010, Amelia Island, Florida.

7. 1888, sheet 4, Western Americana Division, Special Collections, J. Willard Marriott Library, University of Utah, Salt Lake City. Online documentation on the Sanborn Fire Insurance maps for Provo and other cities in Utah can be found at http://www.lib.utah.edu/digital/sanborn/.

8. Digital maps and original data files will be housed at the Church History Library, The Church of Jesus Christ of Latter-day Saints, Salt Lake City.

John H. McBride

BYU Studies Publications