Twin Ariels

My 98 disco 300tdi Safari has two ariels on the roof, one is obviously for the radio, but whats the other one for, did it leave the factory like this ?

Could it be for a cb radio.

If its the one shown in your avatar, its either a 2 way or CB radio. If you can find the aerial lead and see what type of connector is on it. CB is usually an ordinary continual screw on fitting whereas 2 way might have a "twist" on type of connection. Is there any signs of a power lead in and around the dashboard area and any holes where a mic mount could have been fitted to the dash?

No its not the one in my avatar, and its not a cb ariel its only about 18 inches tall

Aw right, I couldnt see it on the picture. The only other aerial that i can think of would be an old mobile phone aerial. They would be about 12-14 inches long. Do you know much about the history of the car?
Reason i ask is that i used to fit mobile phone systems to customer cars but the cars were mainly owned by businesses as opposed to privately owned. Also, i tended to fit the glass mounted aerial as it was one less hole to have in the bodywork.

yes it must be an old mobile fone ariel