Nanoscale fluid dynamics, or nanofluidics, is an rising area of analysis the place the continuum of hydrodynamics meets the atomic nature of matter1. Understanding the legal guidelines that govern liquid flows at such molecular scales is of key sensible significance: they decide the efficiency of seawater desalination membranes, and the way in which ions permeate via the pores in our cells. For electron flows in solids, it’s now historical past that scale discount yields qualitatively new behaviour, which is on the foundation of the entire nanoelectronics business. But, for water flows and ion transport therein, the legal guidelines established on the macroscopic scale maintain surprisingly effectively on the molecular scale. A water molecule is about 0.3 nm in diameter; but the Navier–Stokes equation — the fundamental equation of hydrodynamics — nonetheless holds in 1-nm-wide channels2. Now, writing in Nature Nanotechnology, Noy, Blanckschtein and coworkers3 reveal that the Nernst–Einstein relation — a elementary regulation that governs ion dynamics in resolution — breaks down in extraordinarily slender carbon channels that confine water and ions to a single one-dimensional chain.