What is the "Flame of Arnor?"

[Hawkblaze]

I just finished The Silmarillion and I hoped to figure out what the Flame of Arnor is when Gandalf challenges the Balrog on the Bridge, but absolutely nothing appears on the subject. Could it be the Ring of Fire? Any answers would be appreciated.

 

[Ingolmin]

Firstly Secret Fire or the Flame of Anor means The Flame Imperishable which is the source of all creation(light).
Gandalf meant by saying these lines that he was a servant of the Lords of West and his weapon was Light that is creation. Light is more powerful than darkness(destruction) which was the only weapon of the servants of Melkor.
It not at all means that he drew his power from the Ring of Fire.
Ring of Fire was nothing in front of the Flame Imperishable, it is just like comparing a great sword with a pen knife.
Also the Ring of Fire was not a ring of power.