Philosophical Letters, by Margaret Cavendish 53679 [Full title: Philosophical Letters: or, modest Reflections upon some Opinions in Natural Philosophy] [Link: http://www.gutenberg.org/5/3/6/7/53679 ] [Files: 53679-8.txt; 53679-h.htm] Thanks to Dr. Clare Graham and Marc D'Hooghe at Free Literature (online soon in an extended version, also linking to free sources for education worldwide ... MOOC's, educational materials,...) Images generously made available by the Internet Archive. Regards, Al