Changes

'''Inertia''' is a property of matter that causes it to resist changes in [[velocity]]; or, in other words, the resistance against being set in [[motion]], and resistance to being stopped when in motion.<ref name="KelvinTides">{{cite web |title=August 25, 1882 |author=W. Thomson (Lord Kelvin) |publisher= The British Association, The Glasgow Science Lectures Association |year=August 25, 1882 |Chapter= Appendix A |url=http://zapatopi.net/kelvin/papers/the_tides.html |aaccessdate=June 13, 2015}}</ref>

'''Inertia''' is a property of matter that causes it to resist changes in [[velocity]]; or, in other words, the resistance against being set in [[motion]], and resistance to being stopped when in motion.<ref name="KelvinTides">{{cite web |title=August 25, 1882 |author=W. Thomson (Lord Kelvin) |publisher= The British Association, The Glasgow Science Lectures Association |year=August 25, 1882 |Chapter= Appendix A |url=http://zapatopi.net/kelvin/papers/the_tides.html |aaccessdate=June 13, 2015}}</ref>

[[Newton]] [[scientific discovery|discovered]] that bodies which have equal [[heaviness]] have equal ''inertia'', i.e. that if the property of inertia is possed to an equal degree by two different [[substance]]s, the have equal heaviness. One of his [[proof]]s was founded on the celebrated guinea and feather [[experiment]], showing that the guinea and feather fall at the same rate when the resistance of the [[air]] is removed. Another was founded upon making pendulums of different substances—[[lead]], [[iron]], and [[wood]] to vibrate, and [[scientific observation|observing]] their times of [[vibration]].<ref name="KelvinTides"/>   

[[Newton]] [[scientific discovery|discovered]] that bodies which have equal [[heaviness]] have equal ''inertia'', i.e. that if the property of inertia is possed to an equal degree by two different [[substance]]s, the have equal heaviness. One of his [[proof]]s was founded on the celebrated guinea and feather [[experiment]], showing that the guinea and feather fall at the same rate when the resistance of the [[air]] is removed. Another was founded upon making pendulums of different substances—[[lead]], [[iron]], and [[wood]] to vibrate, and [[scientific observation|observing]] their times of [[vibration]]. This discovery is the very essence of the Newton's 'first great point' pertaining to the law of [[gravitation]]. The other is that the force between any two bodies diminishes as the distance increases, according to the law of inverse square of the distance.<ref name="KelvinTides"/>   

==References==

==References==