{"version":"1.0","type":"rich","provider_name":"EbookNetworking","provider_url":"https://www.ebooknetworking.net","title":"A Treatise on the Principal Mathematical Instruments Employed in Surveying, Levelling, and Astronomy","author_name":"Frederick Walter Simms","thumbnail_url":"https://www.ebooknetworking.net/books/111/008/big1110089953.jpg","thumbnail_width":330,"thumbnail_height":500,"html":"<a href=\"https://www.ebooknetworking.net/books_detail-1110089953.html\">A Treatise on the Principal Mathematical Instruments Employed in Surveying, Levelling, and Astronomy</a>","width":400,"height":300}