// Each hour between 6 October 2014, 12:00 and 6 October 2014, 15:00
var result = eachHourOfInterval({
start: new Date(2014, 9, 6, 12),
end: new Date(2014, 9, 6, 15)
})
//=> [
// Mon Oct 06 2014 12:00:00,
// Mon Oct 06 2014 13:00:00,
// Mon Oct 06 2014 14:00:00,
// Mon Oct 06 2014 15:00:00
// ]