 The inquiry rejected the conclusion of the coroner's jury that the block system was at fault and "had proved ineffective in a case of emergency", riposting ""such a conclusion, natural enough on a superficial view to those who are not thoroughly versed in the subject, really results from a confusion of ideas"".The problem was with signals, and any system of working railways must be ineffective if signals could not be relied upon.The immediate cause was the accumulation of snow on the semaphore arms and/or control wire of several sets of signals.