Thus when they left Everett the express was fairly chasing the accommodation train, and overtaking it with terrible rapidity. Even then no collision ought to have been possible. Unfortunately, however, the road had no system, even the crudest, of interval signals; and the utter irregularity prevailing in the train movement seemed to have demoralized the employés along the line, who, though they noticed the extreme proximity of the two trains to each other as they passed various points, all sluggishly took it for granted that those in charge of them were fully aware of their relative positions and knew what they were about. Thus, as the two trains approached the Revere station, they were so close together as to be on the same piece of straight track at the same time, and a passenger standing at the rear end of the accommodation train distinctly saw the head-light of the express locomotive. The night, however, was not a clear one, for an east wind had prevailed all day, driving a mist in from the sea which lay in banks over the marshes, lifting at times so that distant objects were quite visible, and then obscuring them in its heavy folds. Consequently it did not at all follow, because the powerful reflecting head-light of the locomotive was visible from the accommodation train, that the dim tail-lights of the latter were also visible to those on the locomotive. Here was another mischance. The tail-lights in use by the company were ordinary red lanterns without reflecting power.