It starts from a fact and it often explicitly appeals to facts.
Pliny explicitly speaks of a mineral Katiµ€ia or cadmic as serving for the conversion of copper into aurichalcum, and says further that the deposit (of zinc oxide) formed in the brass furnaces could be used instead of the mineral.
Introits were provided for use on every Sunday and Holy-Day; after the offertory intending communicants were directed to " tarry still in the quire or in some convenient place nigh the quire "; in the prayer " for the whole state of Christ's church," the blessed Virgin Mary was commemorated by name among departed saints; prayer for the departed was explicitly retained; also an invocation of the Holy Spirit before the words of institution, the prayer of oblation immediately following them.
Denis in 1837 says explicitly that Barbarossa was the name applied by Christians to Khair-ed-Din.
The question was explicitly suggested by the report that the Egyptian priest in the Oasis had hailed him in the god's name as the son of Ammon.