As No. 4 approached the interlocking tower at Shops Junction, tower operator J. S. Johnson showed a clear signal from the tower's train order signals, indicating all was clear. As he stopped to record the train in his logs, he noticed that there was no entry showing that the opposing train No. 1 had passed. Johnson reported to the dispatcher who telegraphed back, "He meets No. 1 there, can you stop him?" Johnson sounded the emergency whistle, but there was no one at the rear of No. 4 to hear it. The train passed on the assumption that the clear train order board indicated that the line ahead was clear. Also, the engineman and conductor failed to visually inspect the train register at Shops Junction to ascertain as to whether No. 1 had yet arrived. That was required by operating instructions issued by the railroad's management prior to the wreck.