CHICORA METEORITE — PRESTON, HENDERSON, RANDOLPH 397 



Having obtained these bearings of the smoke trail, reconstructed 

 from memory alter a lapse of some weeks, we have plotted them on the 

 United States topographical survey, 1/62,500 scale (roughly 1 inch to 

 the mile), by means of strings stretched in the air above the maps, and 

 in this way have tried to locate the correct trajectory (pi. 56). It is to 

 be assumed that the trajectory will be nearly a straight line, and quite 

 straight as seen in plain view. 



The first sound of the "explosion" reaches a given spot on the 

 ground, from the nearest point of the trajectory, or very nearly, since 

 the meteor is traveling many times as fast as the velocity of sound. 

 The succeeding sustained roar is due to the expansion of the air in 

 both earlier and later parts of the trajectory. If the time interval 

 were known with precision in any case, the length of the radius vector 

 to the nearest point on the trajectory would be known with fair 

 accuracy. 



Ai'ound Chicora the time delay is reported as very slight. At 

 Butler it was reported as about 8 seconds after the track was seen to 

 expand {17), but that is probably an underestimation. At Station 

 KDKA (Saxonburg), where the radio operators are extremely "time- 

 conscious" and know exactly at what stage the signing-off of the 

 program stood, the delay was at least 31 seconds. At Cooperstown 

 one observer {11) saw the flash, and then the trail, and immediately 

 called wildly for another {35) to come and look. The latter young lady 

 was in the locker room, getting dressed for swimming, and ran out 

 as soon as she could. She arrived ahead of the thunder peal by at 

 least several seconds. I had her reenact the scene from the same 

 degree of dishabille in the locker room, and she was out in 24 seconds. 

 This sets a minimum limit, but the general belief of the four persons 

 present was that the explosion was delayed a good many seconds 

 beyond the 24. This places the trajectory at least 5 or 6 miles away. 

 Beyond agreeing with the KDKA reports, these observations are of 

 httle help. 



PROBABLE TRAJECTORY 



Plate 56 shows a map of the central part of the terrain in which 

 the phenomenon was observed, and the thin black lines are black 

 threads representing observations, with a "transit" (theodolite) from 

 various places on the ground, of the line of sight to some point on the 

 smoke trail. Each thread arises from a thumbtack representing the 

 position of the eyewitness, who was then asked to set the instrument 

 on the highest point of the smoke trail and on the lowest point, as 

 nearly as he could remember. 



If every observer had been accurate, or if each could have had a 

 transit all set up and ready to take the observations when the meteorite 



