Where and when do you get the Dowsing Machine in pokemon B/W?

Question

Going on a big rare candy hunt =D

Answer 1

YOu get it in Nacrene City, from Bianca.

Answer 2

When you beat Lenora, the Gym Leader in Nacrene city, Team Plasma will show up and take the dragon skull, You and Lenora then go outside the museum where Burgh, the Gym Leader in Castelia, shows up, Lenora introduces you and Burgh and then Bianca and Cheren turn up. Lenora decides you should split up, Cheren and Bianca stay at the museum, Lenora heads east and you and Burgh go to Pinwheel Forest. The two Leaders go on ahead and then Bianca gives you the dowsing machine before going inside with Cheren. You must then go west to Pinwheel Forest.

Answer 3

when you beat Lenora(the gym leader)team plasma will show up and take the dragon skull and when you go outside with lenora then Cheren and Binaca will come then she will give you the dowsing MCHN