Steam-liners had masts for mainly four reasons (although they did serve other purposes, this varied ship to ship)
Steamships (APEX)
masts are sails on yachts.
there was 3 masts on the mayflower
Masts are the poles that hold sail up.
Battle of the Masts happened in 655.
Masts of Manhatta was created in 2010.
A decrease use of steamships (apex)
It was a steam ship, so no masts for sails.
The masts were probably made out of wood.
You might be thinking about the sailing vessel known as a "clipper", a very fast sailing ship of the 19th century that had three or more masts and a square rig.
metal and stone
Schooners and clippers have three or more masts...