2-8-4 lines. The JNR rebuilt a total of 104 locomotives to the 2-8-4 wheel arrangement from its older 2-8-2 Mikado classes, the Class D50, Class D51 and Class D52. Some of these locomotives survived in service up to the end of steam traction on the JNR in 1974. In 1951, Mexico’s "Ferrocarriles Nacionales de México" (N de M) bought five 2-8-4 locomotives, built by Baldwin Locomotive Works in 1940, from Norfolk Southern Railway in the United States of America (USA), where they had become redundant due to dieselisation. Before their arrival in Mexico, all five went through a complete major overhaul
Minim (unit) size of a drop can vary considerably depending upon the viscosity and specific gravity of the liquid. (At the time, the phenomenon of surface tension was not well understood.) The minim, on the other hand, was measured with a graduated glass tube known as a "minimometer", later known as the minim-tube. The minim-tube was a type of graduated pipette, a device invented in 1791 by François-Antoine-Henri Descroizilles. Apothecaries' measures are fully defined in the United Kingdom's Weights and Measures Act of 1878, but the UK's 1963 Weights and Measures Act provided for the abolition of the minim, fluid scruple, and