Sentence:  Carried somehow, somewhither, for some reason, on these surging floods, were these travelers, of errand not wholly obvious to their fellows, yet of such sort as to call into query alike the nature of their errand and their own relations. It is easily earned repetition to state that Josephine St. Auban's was a <WSD>presence</WSD> not to be concealed. 
Meaning of the word marked with <WSD> tags:  The fact or condition of being present, or of being within sight or call, or at hand.