BORE-HOLE INVESTIGATIONS 1117 



2,221,951 Issued Nov. 19, 1940. W. D. Mounce and W. M. Rust, Jr. "Making Elec- 

 trical Measurements." 



2,222,149 Issued Nov. 19, 1940. E. Lipson. "Method and Apparatus for Logging 

 Wells." 



2,222,182 Issued Nov. 19, 1940. W. D. Mounce and W. M. Rust, Jr. "Earth Imped- 

 ance Measuring Device." 



2,222,608 Issued Nov. 26, 1940. R. D. Elliott. "Electrical Surveying in Drill Holes." 



2,224,635 Issued Dec. 10, 1940. E. Lipson. "Alternating Current Method and Appa- 

 ratus for Logging Wells." 



2,225,668 Issued Dec. 24, 1940. P. Subkow and L. Dillon. "Method and Apparatus 

 for Logging Drill Holes." 



2,229,604 Issued Jan. 21, 1941. D. Silverman. "Electrical Logging." 



2,230,502 Issued Feb. 4, 1941. J. M. Pearson. "Electrical Prospecting Method and 

 Apparatus." 



2,230,999 Issued Feb. 11, 1941. H. G. Doll. "Methods of Indicating Spontaneous 

 Potentials in Shallow Wells." 



2,233,420 Issued March 4, 1941. E. G. Leonardon. "Method and Apparatus for 

 Exploring Drill Holes." 



2,236,668 Issued April 1, 1941. L. W. Blau and R. R. Thompson. "Method and Appa- 

 ratus for Logging Wells." 



2,239,466 Issued April 22, 1941. J. Neufeld. "Method and Apparatus for Electrical 

 Investigation of Drill Holes." 



2,242,161 Issued May 13, 1941. L. F. Athy and H. R. Prescott. "Method of Logging 

 Drill Holes." 



2,242,612 Issued May 20, 1941. E. G. Leonardon. "Method for Determining the Beds 

 Traversed by Drill Holes." 



2,245,700 Issued June 17, 1941. W. D. Mounce. "Resistance Thermometer." 



2,246,460 Issued June 17, 1941. C. B. Bazzoni and J. M. Pearson. "Electrical Pros- 

 pecting Apparatus." 



2,247.417 Issued July 1, 1941. D. Silverman and R. W. Stuart. "Electrical Logging." 



2,248,101 Issued July 8, 1941. R. W. Lohman. "Method and Apparatus for Investigat- 

 ing Subterranean Strata." 



2,249,769 Issued July 22, 1941. E. G. Leonardon. "Electrical System for Exploring 

 Drill Holes." 



2,251,900 Issued Aug. 5, 1941. B. S. Smith. "Well Surveying." 



2,253,485 Issued Aug. 19, 1941. C. B. Bazzoni and J. Razek. "Electrical Prospecting 

 Method and Apparatus." 



2,255,754 Issued Sept. 16, 1941. L. C. Beers. "Multiple Record Electrologging of 

 Wells." 



2,259,904 Issued Oct. 21, 1941. B. F. McNamee and F. Rieber. "Method and Appa- 

 ratus for Logging Boreholes." 



2,264,318 Issued Dec. 2, 1941. F. W. Lee. "Geophysical Surveying.'* 



2,261,563 Issued Nov. 4, 1941. F. Rieber. "System for Measuring Earth Conductivity." 



2,262,419 Issued Nov. 11, 1941. L. F. Athy and H. R. Prescott. "Method of Electro- 

 magnetic Logging." 



2,264,318 Issued Dec. 2, 1941. F. W. Lee. "Geophysical Surveying." 



2,265,978 Issued Dec. 16, 1941. D. E. Batchelder. "Alternating Current Electro- 

 Logging of Well Bores." 



2,266,071 Issued Dec. 16, 1941. R. G. Piety. "Well Surveying Device." 



2,268,137-8 Issued Dec. 30, 1941. H. M. Evjen. "Electrical Well Logging System." 



2,269,269 Issued Jan. 6, 1942. F. W. Jessen. "Well Logging." 



2,271,951 Issued Feb. 3, 1942. J. M. Pearson and G. A. Smith. "Electrical Prospect- 

 ing Alethod and Apparatus." 



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



2,273,363 Issued Feb. 17, 1942. E. Lipson. "Method for Electrical Investigation of 

 Cased Drill Holes." 



2,274,248 Issued Feb. 24, 1942. S. A. Scherbatskoy and J. Neufeld. "Well Surveying 

 Method." 



2,281,766 Issued Alay 5, 1942. P. F. Hawley. "Logging of Permeable Formations 

 Traversed by Wells." 



2,281,960 Issued May 5, 1942. V. V. Vacquier. "Apparatus for Logging Bores." 



2,288,876 Issued July 7, 1942. J. C. Arnold. "Magnetic Logging." 



