1120 EXPLORATION GEOPHYSICS 



2,302,247 Issued Nov. 17, 1942. J. Neufeld. "Well Surveying Method and Apparatus." 



2,303,688 Issued Dec. 1, 1942. R. E. Fearon. "Well Surveying Method and Appa- 

 ratus." 



2,303,709 Issued Dec. 1, 1942. A. J. F. Siegert. "Subsurface Prospecting." 



2,308,361 Issued Jan. 12, 1943. R. E. Fearon. "Well Logging Method and Device." 



2,316,329 Issued April 13, 1943. D. G. C. Hare. "Subsurface Prospecting." 



2,334,262 Issued Nov. 16, 1943. D. G. C. Hare. "Sursurface Prospecting." 



2,345,119 D. G. C.Hare. 



2,349,712 R. E. Fearon. 



2,390,433 Issued Dec. 4, 1945. R. E. Fearon. "Well Survey Method and Apparatus." 



2,398,324 Issued April 9, 1946. B. Pontecorvo. "Well Surveying." 



2,408,230 Issued Sept. 24, 1946. W. E. Shoupp. "Measuring Apparatus." 



RADIOACTIVITY LOGGING 



2,197,453 Issued April 16, 1940. G. L. Hassler. "Method of Underground Explora- 

 tion." 



2.219.273 Issued Oct. 22, 1940. S. A. Scherbatskoy. "Well Logging by Measurements 

 of Radioactivity." 



2.219.274 Issued Oct. 22, 1940. S. A. Scherbatskoy. "Well Survey Method and 

 Apparatus." 



2,220,205 Issued Nov. 5, 1940. S. E. Buckley. "Method of Locating Detectable Ce- 

 ment in a Bore Hole." 



2,273,215 Issued Feb. 17, 1942. J. Neufeld. "Well Surveying Method and Apparatus." 



2,289,926 Issued July 14, 1942. J. Neufeld. "Well Survey Method and Apparatus." 



2,308,176 Issued Jan. 12, 1943. L. G. Howell. "Operations in Boreholes." 



2,313,310 Issued March 9, 1943. J. C. Arnold. "Well Bore Radiation Logging Appa- 

 ratus." 



2,315,355 Issued March 30, 1943. S. A. Scherbatskoy. "Well Surveying Method and 

 Apparatus." 



2,316,576 Issued April 13, 1943. R. E. Fearon. "Well Surveying Method and Appa- 

 ratus." 



2,320,643 Issued June 1, 1943. J. Neufeld. "Well Surveying Method and Apparatus." 



2,320,890 Issued June 1, 1943. W. L. Russell. "Method of Geophysical Prospecting." 



2,320,892 Issued June 1, 1943. S. A. Scherbatskoy, and R. E. Fearon. "Method of 

 Geophysical Prospecting." 



2,321,295 Issued June 8, 1943. L. G. Howell. "Apparatus for Logging Boreholes." 



2,322,634 Issued June 22, 1943. L. B. Howell and L. W. Blau. "Method and Appa- 

 ratus for Logging Boreholes." 



2,332,873 Issued Oct. 26, 1943. D. Silverman. "Differential Radioactivity Logging." 



2,337,269 Issued Dec. 21, 1943. R. G. Piety. "Marking Device." 



2,339,129 Issued Jan. 11, 1944. M. M. Albertson. "Radiological Method of Surveying 

 Wells." 



2,346,789 Issued April 18, 1944. E. E. Roper. "Well Logging." 



2,349,366 Issued May 23, 1944. C. A. Moon. "Method for Geophysical Prospecting." 



2,352,433 Issued June 27, 1944. G. Herzog. "Well Logging." 



2,352,993 Issued July 4, 1944. M. M. Albertson. "Radiological Method of Logging 

 Wells." 



2,353,619 Issued July 11, 1944. B. Pontecorvo and G. Swift. "Geophysical Pros- 

 pecting." 



2,358,945 Issued Sept. 26, 1944. C. F. Teichmann. "Method of Determining the 

 Porosity and Location of Permeable Formations in Oil Wells." 



2,361,274 Issued Oct. 24, 1944. A. M. Cravath and G. L. Hassler. "Radiological 

 Exploration System." 



2,361,389 Issued Oct. 31, 1944. R. E. Fearon. "Well Survey Method and Apparatus." 



2,362,164 Issued Nov. 7, 1944. D. Silverman. "Radioactivity Logging." 



2,364,975 Issued Dec. 12, 1944. J. J. Heigl and L. R. Hodell. "Determining Permea- 

 bility of Geological Structure." 



2,368,486 Issued Jan. 30, 1945. J. J. Mullane. "Well Logging." 



2,368,532 Issued Jan. 30, 1945. R. E. Fearon. "Well Surveying Method and Appa- 

 ratus." 



2,369,672 Issued Feb. 20, 1945. D. G. C. Hare. "Method and Apparatus for Logging 

 Boreholes." 



