the mind is ignorant of a fact, its condition still remains sound; the power of thinking, of judging, of willing, is just as complete before communication of the fact as after; the essence or texture, so to speak, of the mind, is not, as in the case of insanity, affected or impaired. Ignorance of a particular fact consists in this: that the mind, although sound and capable of healthy action, has never acted upon the fact in question, because the subject has never been brought to the notice of the perceptive faculties. Meeker v. Boylan, 28 N. J. Law, 274.