June 18, 1876. I had imagined the Emperor of Brazil [Dom Pedro II] to be a dark swarthy tall man of 45 years; that he would not really have a crown upon his head, but that I should feel it was somewhere around … and that I should know I was in Royal presence. But he turns out to be a large old man, say 65, broad-headed and broad shouldered, with a big white beard and a very pleasant, even chatty manner … . As he entered the Dome, he turned to ask who the photographs of Father and Mother were. Once in the Dome, he seemed to feel at home. To my astonishment he asked me if Alvan Clark made the glass of the Equatorial … I remarked, “you have been in observatories before,” and he said, “Oh yes, Cambridge and Washington.” He seemed much more interested in the observatory than I could possibly expect … .
Maria had the opportunity to show many well-known people through the Vassar College Observatory which was not just her place of work, but her home as well. Throughout her life, Maria met with and maintained friendships with some of the well-know scientists and other luminaries of her time including, Nathaniel Hawthorne, Sir George Airy, Sir John Herschel, Harriet Hosmer, Dorthea Dix, Elizabeth Cady Stanton, John Greenleaf Whittier, and Susan B. Anthony to name just a few.