{"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; Explaining Their Construction, Adjustments, and Use","author_name":"Frederick W. Simms","thumbnail_url":"https://www.ebooknetworking.net/books/B01/96I/bigB0196IC0UO.jpg","thumbnail_width":330,"thumbnail_height":500,"html":"<a href=\"https://www.ebooknetworking.net/books_detail-B0196IC0UO.html\">A Treatise on the Principal Mathematical Instruments Employed in Surveying, Levelling, and Astronomy; Explaining Their Construction, Adjustments, and Use</a>","width":400,"height":300}