Genesis 8:4

the seventh month, &c. The Flood had begun on the 17th day of the 2nd month (see Genesis 7:11): the highest point of the Flood is reached on the 17th day of the 7th month. Five months have elapsed. Probably the 150 days were reckoned as five months of 30 days each.

the mountains of Ararat Ararat is not a mountain, but a district mentioned in Isaiah 37:38; Jeremiah 51:27. It is the country which appears in the Assyrian inscriptions as "Urartu." It lies between the river Araxes and Lake Van. It comprises a large portion of Armenia. There were high mountains in Ararat; and the loftiest among them, called in the present day Mount Ararat, is over 16,000 ft. high.

Assuming that the tradition referred to this mountain as the highest known, and that the water was said to have covered it by 15 cubits (Genesis 7:20), the very existence of mountains of the altitude of Mount Everest (31,000 ft. high) was not contemplated. It is more probable that a well-known name like Ararat was accepted, in the Hebrew version of the story, for some similarly-sounding, but less familiar, name of hills in the neighbourhood of the Tigris.