If Robert Bruce didn't talk about them, then you might as well forget it, 'cause they don't exist. Unless he left them out for some mysterious reason, like we're not prepared to know about them, yet.
Mirador
As far as I am aware there are 3 types of elementals.
First are the 'Classical' elementals of fire, air, water and earth. The belief in these elementals goes back to ancient Greece and they are still used in magickal ceremony today.
Second are the elemental nature spirits. Nature elementals were revered by many pagan religions including the Celts and druids.
The third category are thought elementals which are basically creations of thought (psi) energy.
BTW personally my encounters with elementals has been limited to one negative encounter. I believe that it was an encounter with some form of thought elementals.
That was an ignorant thing to say Mirador. There are things that NO human knows about.
They are spirits that belong the the 4 elements, having a similar hierarchy as angelic spirits. It's been said that they are composed of only one element, have no soul, or free-will for that matter.
They are called:
Sylphs: Air
Undines: Water
Gnomes: Earth
Salamanders: Fire
Robert Bruce didn't talk about them that much in self defence book.
Can anyone share their experience, what do you know about them?