{"version":"1.0","type":"rich","provider_name":"EbookNetworking","provider_url":"https://www.ebooknetworking.net","title":"A Treatise On Mathematical Instruments: Including Most of the Instruments Employed in Drawing, for Assisting the Vision, in Surveying and Levelling, ... : In Which Their Construction, and the Me","author_name":"John Fry Heather","thumbnail_url":"https://www.ebooknetworking.net/books/114/179/big1141797496.jpg","thumbnail_width":330,"thumbnail_height":500,"html":"<a href=\"https://www.ebooknetworking.net/books_detail-1141797496.html\">A Treatise On Mathematical Instruments: Including Most of the Instruments Employed in Drawing, for Assisting the Vision, in Surveying and Levelling, ... : In Which Their Construction, and the Me</a>","width":400,"height":300}