SEISMIC METHODS 933 



2,160,224 Issued May 30, 1939. J. P. Minton. "Seismic Survey." 



2,161,764 Issued June 6, 1939. J. P. Minton. "Apparatus for Recording Seismic 



Waves." 

 2,161,764 Issued June 6, 1939. J. P. Minton. "Method and Means for Recording 



Seismic Waves." 

 2,164,196 Issued June 27, 1939. K. C. Woodyard, C. A. Putnam and H. R. Prescott. 



"Means and Method of Making Geophysical Explorations." 

 2,167,124 Issued July 25, 1939. J. P. Minton. "Apparatus for Recording Seismic 



Waves." 

 2,180,949 Issued Nov. 21, 1939. L. W. Blau, W. D. Mounce and W. M. Rust, Jr. 



"Feedover Device." 

 2,184,313 Issued Dec. 26, 1939. J. E. Owen. "Seismic Surveying." 

 2,184,953 Issued Dec. 26, 1939. A. B. Bryan. "Time Lines Recording Apparatus." 

 2,192,972 Issued March 12, 1940. A. I. Innes. "Seismic Surveying." 

 2,193,620 Issued March 12, 1940. R. T. Cloud. "Attenuator." 

 2,193,769 Issued March 12, 1940. J. P. Minton. "Frequency Multiplication System 



for Seismic Recording." 

 2,203,140 Issued June 4, 1940. W. G. Green. "Seismic Prospecting." 

 2,203,272 Issued June 4, 1940. N. R. Sparks. "Apparatus for Determining Seismic 



Velocities." 

 2,207,398 Issued July 9, 1940. F. M. Floyd. "Seismic Surveying." 

 2,209,100 Issued July 23, 1940. J. P. Minton. "Electrical Seismograph." 

 2,215,297 Issued Sept. 17, 1940. J. E. Owen. "Seismic Surveying." 

 2,216,452 Issued Oct. 1, 1940. J. E. Owen. "Seismic Surveying." 

 2,217,720 Issued Oct. 15, 1940. J. F. Anderson. "Apparatus for Solving Seismo- 



graphic Problems." 

 2,217,806 Issued Oct. 15, 1940. G. Muffly. "Seismograph Prospecting." 

 2,217,828 Issued Oct. 15, 1940. R. D. Wyckoflf. "Seismograph Prospecting Apparatus." 

 2,219,508 Issued Oct. 29, 1940. L. F. Athy and E. V. McCollum. "Method and 



Apparatus for Seismic Surveying." 

 2,229,191 Issued Jan. 21, 1941. H. C. Schaeffer and R. A. Peterson. "Method of 



Making Weathering Corrections." 

 2,230,002 Issued Jan. 28, 1941. J. P. Minton. "Method of Calibrating Field Timing 



Systems." 

 2,231,243 Issued Feb. 11, 1941. R. F. Beers. "Method of and Means for Analyzing 



and Determining the Geologic Strata below the Surface of the Earth." 

 2,231,575 Issued Feb. 11, 1941. L. W. Gardner. "Seismograph Prospecting." 

 2,232,613 Issued Feb. 18, 1941. P. W. Klipsch. "Seismic Prospecting." 

 2,238,023 Issued April 8, 1941. P. W. Klipsch. "Equalizer." 

 2,241,428 Issued May 13, 1941. D. Silverman. "Apparatus for Underwater Seismic 



Surveying." 



2.243.729 Issued May 27, 1941. L. G. Ellis. "Method for Analysis of Seismographic 

 Records." 



2.243.730 Issued May 27, 1941. L. G. Ellis. "Apparatus for Analysis of Seismo- 

 graphic Records." 



2,253,358 Issued Aug. 19, 1941. P. S. Williams. "Seismic Exploration Method." 



RE 22535 E. J. Schimek. 



2,257,187 Issued Sept. 30, 1941. J. E. Owen. "Seismic Surveying." 



2,257,423 Issued Sept. 30, 1941. J. D. Malmqvist. "Determining the Velocity of 



Elastic Waves in the Ground." 

 2,257,859 Issued Oct. 7, 1941. E. E. Rosaire and F. M. Kannenstine. "Method and 



Apparatus for Recording Waves." 

 2,259,478 Issued Oct. 21, 1941. C. G. Morgan. "Geophysical Exploration System." 

 2,260,217 Issued Oct. 21, 1941. E. A. Eckhardt and G. Muffly. "Method of and 



Apparatus for Seismograph Prospecting." 

 2,261,321 Issued Nov. 4, 1941. P. S. Williams. "Seismic Exploration Method." 

 2,263,519 Issued Nov. 18, 1941. O. F. Ritzmann. "Seismograph Prospecting 



Apparatus." 

 2,264,098 Issued Nov. 25, 1941. L. C. Paslay. "Deflection Limiter for Galvanometers." 

 2,265,513 Issued Dec. 9, 1941. K. E. Burg. "Prospecting Method and Apparatus." 

 2,265,538 Issued Dec. 9, 1941. J. P. Minton. "Gain Control for Seismograph 



Amplifiers." 



