Spectroscope, 1872. Instrument of the type developed by Robert Bunsen (1811-1899) and Robert Kirchhoff (1824-1887) during the 1850s. Their work provided a precise tool to make use of Joseph von Fraunhofer's (1787-1826) observatians of dark lines in the solar spectrum (1814). The technique of chemical analysis through spectroscopy has become essential in both terrestrial and astronomical studies. From Spectrum Analysis by H. Schellen. (London, 1872).

Photo website with Rights Managed and Royalty Free stock photos, images, illustrations and footage available for download immediately for commercial and editorial uses. Aflo is a leading independent supplier and producer of stock pictures and visual content. Search and find high quality images and video for design, print, web-use and publishing. Buy photos from our extensive collection of model released and property released sports images. Search some of the most beautiful travel and landscape pictures from our own photographers and license from our large collection of content, modern and archive, focusing on Japan. We provide free research. Register for personal account management and for full use of our Stock Photography website and start to download images now.