Cumulus Studies -46- 



originate , rather than in a region which, like the Schenectady area, is 

 traversed by storms. Chairman Stine of the Operations Committee had 

 had experience as a forecaster in New Mexico, and he strongly recommended 

 that that region be used as a base for experiments with cumulus clouds. This 

 recommendation was seconded by Schaefer, who knew of the work being done 

 in this field by Dr. E. J. Workman's group at the New Mexico School of Mines 

 and who had obtained a promise of co-operation from Workman. 



Accordingly, it was decided to attempt a flight to Albuquerque, New 

 Mexico, to determine whether the radar and other facilities of Dr. Workman's 

 group would be of assistance in this respect. In view of the waning cumulus 

 season even at that location, preparations were made to carry out full-scale 

 tests if proper clouds were formed. 



As a result, members of the project spent three days at Albuquerque 

 during mid-October of 1948. A working arrangement was quickly made with 

 Dr. Workman and his staff for radar tracking and photography of the tests 

 to be made. Two seeding flights were made, one on October 12 and the 

 other on October 14. The second of these two flights was performed under 

 such satisfactory conditions that the results obtained were considered partic- 

 ularly significant.' 20) 



For example, an exceptionally complete aerial photographic record was 

 made of the conditions of the cloud that was seeded from one of the planes, 

 including 176 photographs 4" x 5", plus pictures taken every 45 seconds of a 

 group of instruments giving time, altitude, air speed, heading of the plane, and 

 other pertinent information. Every time a photograph was taken of the cloud, 

 another picture would be taken of a clock and other instruments, thus recording 

 when the photograph was taken ani other significant data. In this way an in- 

 valuable flight record was made of the test. 



Further data were collected on the ground. Lapse -time movies were 

 made of the clouds as seen from the station, as well as a series of still 

 pictures, and radar was used to detect any rain that might fall. Although 

 some excellent supporting data were thus obtained, unfortunately it was not 

 as complete as it might be because of a failure of the radio communication 

 between the airplane and the radar station. But significant radar observa- 

 tions were made, and photographs were taken of the radar scope, giving a 

 complete set of records of radar observations for a considerable period 

 of time. 



Four seeding operations were conducted on the October 14 flight. The 

 details of these seedings and the results obtained were discussed at consid- 

 erable length by Langmuir in an occasional report. (20) But a summary of 

 his findings is to the effect that rainfall was produced over an area of more 



