Uses of Hg:
Often used in Lab work for making thermometers, barometers, diffusion pumps,and other instruments.
Mercury-Vapor lamps and advertising signs
Mercury switches and other electrical apparatus
making some pesticides
making mercury cells
caustic soda and chlorine production
making dental amalgams and preparations
making anti-fouling paint
making batteries
making catalysts
amalgams
Takne from:
http://senior.billings.k12.mt.us/students/mattf/uses.html