The first day is called Day One, not the First Day. There are other words for 'first'. This is interesting because the other days are called 'second', 'third', 'fourth', etc. 'One <ref>{{:t|אחד}}</ref> means 'known ח mist אד', so it could be called the Day of the 'known ח mist א()ד'. <ref group="q">Where is the mist mentioned next?</ref><ref group="a">{{bgw| Ge 2:6 }}