Analysis of information sources in references of the Wikipedia article "Julian (emperor)" in English language version.
In A.D. 363, the Emperor Julian undertook to rebuild the temple, but after considerable preparations and much expense he was compelled to desist by flames which burst forth from the foundations. Repeated attempts have been made to account for these igneous explosions by natural causes; for instance, by the ignition of gases which had long been pent up in the subterraneous vaults.