348 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1960 



tion nuclei preceding and after storms, observations of their electrical 

 nature, especially during the hail-forming period, and carefully 

 planned aerial seeding carried out with high-output silver iodide 

 generators. 



The prevention of damaging hail will be one of the most useful 

 achievements of experimental meteorology. Satisfactory progress 

 will be made only when an adequate program is formulated and 

 carried out. 



6. ACKNOWLEDGMENTS 



The author wishes to acknowledge with deep appreciation the 

 cooperation received from many sources in assembling data for this 

 study. 



In particular to W. Boynton Beckwith, of United Airlines, who 

 provided copies of manuscript maps and secured the hail-damage 

 photos taken by Frontier Airlines personnel; to Steve Fleharty at 

 the U.S. Weather Bureau Airport Office at Grand Island, Nebr., who 

 supplied the local weather data, as well as many excellent samples 

 of hailstones ; to Don C. House of the Severe Local Storms Center of 

 the Weather Bureau at Kansas City, Mo., who supplied upper wind 

 data as well as temperature and moisture soundings ; and to Lt. Gen. 

 Francis H. Griswold, of Offutt Field in Omaha, Nebr., who supplied 

 important information on radar echoes of the storm during its critical 

 phases. 



REFERENCES 



1. Hendeesou, T. J. Northeast Colorado hail suppression project. Final Rep. 



Weather Modification Co., pp. 30-32. San Jose, Calif., 1959. 



2. Foster, D. S., and Bates, F. L. A hail size forecasting technique. Bull. 



Amer. Meteorol. Soc, vol. 32, p. 135, 1956. 



3. House, D. C. Private communication, Apr. 26, 1960. 



4. Painter, P., and Schaefeui, V. J. Permanent replicas of the crystalline struc- 



ture of hailstones. Zeitschr. Agnew. Math, und Phys. (in press). 



5. Schaef£:r, V. J. An adventure in atmospheric science. Weatherwise, vol. 12, 



pp. 183-187, 212-215, 1952. 



6. List, Roland von. Kennzerchen atmospharischer Eispartikeln I and II. 



Zeitschr. Agnew. Math, und Phys., vol. 9, pp. 180-192, 217-234, 1958. 



7. Easley, Wanda. Northeast Colorado hail suppression project. Final Rep. 



Weather Modification Co., pp. 37-44. San Jose, Calif., 1959. 



