My brain asks a fairly simple question that I had not previously contemplated. Today it was the history of the kilogram. I knew that a kilogram was approximately the weight of 1 litre of water (which, funnily enough, was at one time defined as being dependent on the kilo), but beyond that I was ignorant. So today’s mini-history lesson is the origin of the kilogram.

Read it here and you’ll be glad you did :)