During the second half of the 19th century, the centimetre–gram–second system of units was becoming widely accepted for scientific work, treating the gram as the fundamental unit of mass and the "kilogram" as a decimal multiple of the base unit formed by using a metric prefix. However, as the century drew to a close, there was widespread dissatisfaction with the state of units for electricity and magnetism in the CGS system. To begin with, there were two obvious choices for absolute units. of electromagnetism: the ‘electrostatic’ (CGS-ESU) system and the ‘electromagnetic’ (CGS-EMU) system. But the main problem was that the sizes of coherent electric and magnetic units were not convenient in "either" of these systems; for example, the ESU unit of electrical resistance, which was later named the statohm, corresponds to about , while the EMU unit, which was later named the abohm, corresponds to .