The views of Halley and Blagdon on the anomalous sounds from bolides were constrained by the limits of eighteenth-century scientific knowledge. After the discovery of radio waves at the end of the nineteenth century, a physical explanation became possible. Even so, the solution remained far from obvious and the majority of meteor scientists clung to the false psychological theory that the noises were all in the mind. The theory failed to explain how some observers had their attention drawn to a bolide by its strange sounds before it was seen.
This fact, together with the patent honesty of many witnesses and sometimes their impressions of the source of the sounds, often led interviewers to believe that the sounds must be real, although none arrived at a viable explanation. Thus the controversy continued. In the USA Engineering Professor J A Udden interviewed many witnesses of a huge bolide seen from almost the entire State of Texas in 1917. One observer thought the sounds came from "objects attached to the ground" prompting Udden to conclude that the cause may "perhaps be sought in ether waves that, on meeting the earth, or objects attached to the earth, such as plants or artificial structures, are in part dissipated by being transformed into waves of sound in the air." He was close to the truth.
On the other hand Iowa Mathematics and Astronomy Professor C C Wylie, a notable meteor scientist, wrote an article on the subject in which he asserted that "the explanation is without doubt psychological." He claimed that persons knowing that a meteor must be fifty or more miles away never report hearing such sounds. His view was bolstered by cases of such bolides being heard by some and not by others whom he considered to be more favourably located.
Another prominent American meteor expert, H H Nininger, was one of the few to "regard the matter as a problem in physics rather than psychology" and in the last of his papers on the subject he revealed "In 1934, Mr Elmer R Weaver of the US Bureau of Standards suggested to me in conversation that possibly ether waves are transformed into sound upon striking objects in the environment of the observer." Again, very close.
In other countries the controversy raged on. In England another meteor expert, W F Denning upheld the psychological theory on the grounds that the anomalous sounds were sometimes heard by only one or two members of a group of eye-witnesses in close proximity to one another. In the Soviet Union there was the same division of opinion by meteor scientists. Omsk University Professor Peter Dravert believed that the effect must have a physical explanation and coined the term electrophonics to describe it. The great meteor expert I S Astapovich devoted much of his life to a study of electrophonic bolides and found empirically a number of their important characteristics. On the other hand other prominent meteor authorities such as Academician B Yu Levin strongly held to the fallacious psychological theory.
When the Cold War intensified in the late 1950's the tempting prospect of light-speed communications by some as yet undiscovered means spurred the Pentagon to investigate the matter. A contract was awarded to the RAND Corporation. In 1963 their inconclusive report, authored by Mary Romig and Donald Lamar, was released and widely taken to be the last word on the subject. Because no physical means of transfer and conversion of energy to produce the sounds was identified in the RAND report, the psychological misconception continued to hold sway in the minds of the majority of meteor scientists, although some felt uneasy about it.
It is noteworthy that through all the years when this alleged psychological effect was invoked it appears to have been totally ignored by the world's psychologists. Any study, whatever the discipline of the investigator, faced many daunting difficulties. A successful theory of the effect had to explain or overcome several difficult observational problems.