00745cam a2200229 4500 377777640 TxAuBib 20170331120000.0 170612s2017||||||||||||||||||||||||eng|u 54897 Project Gutenberg PGUSA eng TxAuBib Herschel, John F. W, 1792-1871, (John Frederick William.) Preliminary Discourse on the Study of Natural Philosophy [Gutenberg] / John F. W. Herschel. Project Gutenberg, 2017. Public domain in the USA. Text. Science -- Philosophy. Astronomy -- History. Physics -- History. Science -- History. http://www.gutenberg.org/ebooks/54897 TXTLL