424 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1960 



airplane. However, there are still many facets which challenge both 

 the experimentalist and the theorist in this field of natural flight. 

 It is my hope that some of these challenges will be accepted by biol- 

 ogists, physicists, engineers, and mathematicians. 



REFERENCES AND NOTES 



1. LiLiENTHAL, O. Der Vogelflug als Gruudlage der Fliegekunst. Oldeubourg, 



Germany. 1893. New ed., 1943. 



2. Rayleigh, Loed. Nature, vol. 27, letter, 1883. 



3. Feldmann, F. Schweiz. Aero-Rev., vol. 19, p. 219, 1944. 



4. Newman, B. G. Joum. Exp. Biol., vol. 35, p. 280, 1958. 



5. Geaham, R. R. Journ. Roy. Aeron. Soc, vol. 38, p. 837, 1939. 



6. Raspet, A. Aeron. Eng. Rev., voL 9, p. 14, 1950. 



6a. Bird-flight research based on this concept is being conducted by F. D. 

 Farrar, Jr., and C. E. Farrell, of Vanderbilt University, under National 

 Science Foundation sponsorship. 



7. Raspet, A. Aeron. Eng. Rev., vol. 11, p. 52, 1952. 



8. Keamee, M. O. Journ. Aero/Space Sci., vol. 26, p. 69, 1960. 



9. Hankin, E. H. Animal flight. Ulife, London. 1913. 



10. HuFFAKEE, E. C. On soaring flight. Ann. Rep. Smithsonian Inst, for 1897. 



1898. 



11. Raspet, A. Soaring, Jan.-Feb. 1944, pp. 1, 10. 



12. Woodcock, A. H. Sci. Monthly, vol. 55, p. 226, 1942. 



13. Lanqley, S. p. Internal work of the wind. Smithsonian Contr. KnowL, 



vol. 27, No. 2, 1893. 



14. Klempeeee, W. B. Theorie des Segelfluges, Heft 5, 1926. English transl.. 



Soaring, 1943-45. 



15. Bazin, a., in P. Idrac, Etudes exp^rimentales sur le vol il voile. Vivien, Paris. 



1931. 



16. Lanchestee, F. W. Aerodonetics. Constable, London. 1917. 



17. Idbac, p. fitudes exp^rimentales sur le vol a voile. Vivien, Paris. 1931. 



18. Maeey, E. J. Vol des oiseaux. Mason, Paris. 1890. 



19. KiJOHEMANN, D., and Webee, J. Aerodynamics of propulsion. McGraw- 



Hill, New York. 1953. 



20. FiSHEB, H. L. Amer. Midland Nat, vol. 35, p. 545, 1946. 



21. Naylee, J. L., and Simmons, L. F. G. A note relating to experiments in a 



wind channel with an Alsatian swift. Aeron. Res. Counc. Reps, and 

 Mem. No. 708, pp. 915-16, 1920. 



22. LePage, W. L. Journ. Aeron. Soc, vol. 27, p. 114, 1923. 



