 Complete the following phrase:  Regarding the intended use of the beehive niches, a number of theories has arisen. The first known thorough researcher of the subject area was Gyula Bartalos, a historian and archaeologist priest from Eger. His theory was that the beehive rocks had been shrines, with ashes of human remains put into the niches. He linked the carving of rock niches to Hun Hungarians first, and to Celts and Scythians later. Gáspár Klein, a chief archivist of Borsod county, suggested that the dummy windows could have served as idol niches, and dated them to the age of the so-called 