Sentence:  At Christmas, 1890, or <WSD>Newtonmas</WSD>, 248, for the first time, the members of the "Newtonkai", or Newton Association, met in the Physical Laboratory of the Imperial University, to hear each other talk, to distribute appropriate gifts, and to lengthen out the small hours with laughter and good cheer. 
Meaning of the word marked with <WSD> tags:  December 25, Sir Isaac Newton's birthday (in the Julian calendar).