Worth its weight

The redefinition of kilogram is timely

The “Travels of Marco Polo” is an eternal bestseller due to its (rather fanciful) descriptions of life in 13th-century China. But Polo conceptualised it as a handbook of weights and measures, making it invaluable for merchants hampered by the lack of uniformity in measurements. It was the “Metre Convention” of 1875 that established the International Bureau of Weights and Measures and led to universal measurement standards being set for the first time. On November 16, 2018, however, the member-nations of the Bureau unanimously agreed to change the definition of a kilogram (kg). This is the last of seven standard Systeme