After understanding the behaviour of air under different pressure and temperature conditions and their application areas, we have been exploring ways to make a barometric pressure sensor ourselves. We decided on the aneroid barometer and made one successfully. But a design is never complete without understanding the possible sources of error that can occur in any measurement due to unavoidable design limitations. That is when a child recalled the story we had learnt about the Mercury barometers that were first used in the 17th century, and pop came the question!
Of course, the reasons for not using Mercury due to its poisonous nature was accepted. But, along with this came a new set of questions that now need to be explored – why is Mercury poisonous, how is it poisonous and what can it be replaced with in applications that need Mercury?
