The Foothills Trail in Pierce County Washington is 24.1 km long. Here is signage to mark distance along the trail. I am waiting on permission from the governing body of the trail to post these signs. Has anyone else done something similar? by: lpsweers@comcast.net

120 year old cylinder that defines the world standard for one kilogram to be replaced by sphere of silicon 28

The 120 year old International Prototype that defines the world's standard for the mass of one kilogram, held at the International Bureau of Weights and Measurement in Paris (BIPM), is set to be replaced by a perfect silicon crystal sphere developed by scientists at Australia's CSIRO.