X-6. HEEZEN, B. C, THARP, MARIE, and EWING, MAURICE. The 

 floors of the oceans. Pt. I, The North Atlantic. Geological 

 Society of America. Special Paper No. 65. New York. 122 p. 

 1959. 



X-7. HERSEY, J. B. Tests of the Edgerton Thumper in Vineyard 

 Sound, from ATLANTIS. Woods Hole Oceanographic Institution. 

 Technical Memorandum 1-60. "Woods Hole. 5 p. March I960. 



X-8. - - - and EWING, MAURICE. Seismic reflections from beneath 

 the ocean floor, Transactions , American Geo ph ysical Union , 

 vol. 30, no. 1, p. 5-14, 1949. 



X-9. HOUGH, J. L. Bottom sampling apparatus, p. 631-664. In: Trask, 

 P. D., ed. Recent marine sediments, a symposium. American 

 Association of Petroleum Geologists. Tulsa, Okla. 736 p. 1939. 



X-10. HVORSLEV, M. J. Subsurface exploration and sampling of soils 

 for civil engineering purposes. Report on a research project 

 of the Committee on Sampling and Testing, American Society 

 of Civil Engineers. Vicksburg, Miss: Waterways Experiment 

 Station. 521 p. 1949. 



X-ll. and STETSON, H. C. Free-fall coring tube; anew gravity 



bottom sampler, Bulletin of the Geo g raphical Society of America , 

 vol. 57, p. 935-950, 1946. 



X-12. KNOTT, S. T., and HERSEY, J. B. High- re solution echo- 

 sounding techniques and their use in bathymetry, marine geo- 

 physics, and biology, Deep - Sea Research , vol. 4, p. 36-44, 1956. 



X-13. KULLENBERG, BORGE. The piston core sampler, Svenska 

 H ydro g rafisk-Biolo g iska Kommissionens Skrifter, Tredje Serien: 

 Hydrografi, vol. 1, no. 2, p. 1-46, 1947. 



X-14. LA FOND, E. C, and DIETZ, R. S. New snapper-type sea floor 

 sediment sampler, Journal of Sedimentar y Petrolog y, vol. 18, 

 p. 34-37, 1948. 



X-15. LISICYN, A. P., PETELIN, V. P., and UDINCEV, G. B. Anew 

 achievement of Soviet marine geology; the Sysoyev-Kusinov 

 hydrostatic core- sampler, Priroda, no. 6, p. 63-66, 1954. 

 Translated by E. R. Hope, Directorate of Scientific Information 

 Service, Canada, T206R. (Hydrographic Office Translation 365.) 

 5 p. 



X-7 



