Letter from Geo Fras [George Francis] Fitzgerald, Trinity College, Dublin, to [Joseph] Larmor Fitzgerald has been busy with glacier flow and flying machines, but he thinks that Larmor's equation considered the inside of matter moving past fixed electrons, applied with matter moving with electrons. Moving electrons do not have the same distribution of displacement as fixed ones, and Fitzgerald gives an example of how this would affect Larmor's case. He thinks it may be a hole in the investigation, but he is not sure. The question of mass and effective inertia is an interesting one, he thinks, and Larmor has not considered how far inertia would be changed by two electrons close to one another. He discusses this, wondering what force keeps them apart. He notes Karl Pearson's publication on gravity theory, thinking it 'most improbable' and giving his reasoning. 4 April 1895