Actually his tape measure might be OK... Did you take a look at the rock that has the "benchmark" on it from 1842 that provides a precise datum from which they are extracting 0.75mm changes from? http://www.sciencedaily.com/images/2010/10/101020091855.jpg http://www.sciencedaily.com/releases/2010/10/101020091855.htm? Which part of this badly weathered and smeared "brass datum" do you think that they are using to measure their 0.75mm changes from? 0.75mm is less than 1/32 of an inch. Common sense needs to prevail.