2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/209535A method of measuring time intervals by a single observer proposed by Crowell is extended to the more general case when the events separated by the time interval take place at two points characterized by the same y=y' space coordinates. We show that time dilation and time contraction can take place or even an inversion in the time succession can be detectedGeneral Physicstext