Saffron City.
You have to go to Silph Co in Pokemon LeafGreen. You have to go there to get the Silph scope, which you need to advance.
On the 5th floor of silph co.
7th floor.
you get it in silph co which is in saffron city. after the boss fight, the leader of silph co gives you one.
Get the silph scope at silph co in Saffron city. Then you'll be able to fight the ghosts.
Save Silph Co., Just like in Blue.
In Silph Co. in Saffron city. After you get to the top of the building.
Somebody will give it to you at the Silph Co. in Saffron city.
saffron citysilf is actually spelled silph co.
You can only get one masterball.the owner of silph co gives it to you.
Help silph co then talk to the president he gives the masterball to you.
You get it form the owner of the Silph Co building after you save him.