"What, however is abundantly clear on all the authorities is that the answer to the relevant question is pre-eminently an issue of fact for the Industrial Tribunal and it is seldom that an appeal from its decision will lie. Dependent on the circumstances of the particular case, an Industrial Tribunal may wish to consider the manner in which and reason for which the employee was dismissed, including the extent to which, if at all, the employer's conciliatory appeals machinery has been used. It will no doubt investigate what was the substantial cause of the employee's failure to comply with the statutory time limit; whether he had been physically prevented from complying with the limitation period, for instance by illness or a postal strike, or something similar. It may be relevant for the Industrial Tribunal to investigate whether at the time when he was dismissed, and if not then when thereafter, he knew that he had the right to complain that he had been unfairly dismissed; in some cases the Tribunal may have to consider whether there has been any misrepresentation about any relevant matter by the employer to the employee. It will frequently be necessary for it to know whether the employee was being advised at any material time and, if so, by whom; of the extent of the adviser's knowledge of the facts of the employee's case; and of the nature of any advice which they may have given to him. In any event it will probably be relevant in most cases for the Industrial Tribunal to ask itself whether there has been any substantial fault on the part of the employee or his adviser which has led to the failure to comply with the statutory time limit. Any list of possible relevant considerations, however, cannot be exhaustive and, as we have stressed, at the end of the day the matter is one of fact for the industrial tribunal, taking all the circumstances of the given case into account."