Horus and Ladders, Osiris and Steps (Freemasonry)

I've often seen the ladder symbolism used in Masonry referred to as "Jacob's Ladder." Like many things involving the occult, I find it more productive to go to sources that are not speculative or misleading; sources outside the realm and yet related i.e. ancient sources, sources about ancient symbolism and the like. For an understanding of the ladder and the staircase, I quote two excerpts from the 1923 work by Brian Brown called The Wisdom of the Ancient Egyptians.

The Ladder is a symbol of Horus, and was worn [as an amulet in ancient Egypt] to secure his assistance in overcoming and surmounting difficulties in the material world, as well as to form a connection with the heaven world, or land of light. The earliest traditions place this heaven world above the earth, its floor being the sky, and to reach this a ladder was deemed necessary. From the pyramid texts it seems there were two stages of ascent to the upper paradise, represented by two ladders, one being the ladder of Sut, forming the ladder of ascent from the land of darkness, and the other the ladder of Horus reaching the land of light.

The Steps are a symbol of Osiris, who is described as the god of the staircase, through whom it was hoped the deceased might reach the heaven world and attain everlasting bliss.

Very simple and straightforward.