Sentence:  But by the tracing procedure , he could , in a strange <WSD>obviously</WSD> kinesthetic manner , find the unseen form ; could piece , as it were , the jumbled mass together into an organized whole and then recognize it as a man or a triangle or whatever it turned out to be . 
Meaning of the word marked with <WSD> tags:  unmistakably (`plain' is often used informally for `plainly')