{"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/B01/145/bigB011450AMM.jpg","thumbnail_width":330,"thumbnail_height":500,"html":"<a href=\"https://www.ebooknetworking.net/books_detail-B011450AMM.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}