{"product_id":"2940149222605","title":"The Invention of the Railroad Track Circuit","description":"PREFACE \u003cbr\u003eBelieving that no more fitting memorial can be prepared in honor of Dr. William Robinson than to reproduce the salient points relating to his great achievement as written and published by himself in 1906 under the title of \"History of Automatic Electric and Electrically Controlled Fluid Pressure Signal Systems for Railroads,\" the committee has accordingly drawn largely from this pamphlet for the material contained in Part I. \u003cbr\u003ePart II is devoted to W. A. Baldwin, formerly General Superintendent of the Pennsylvania Railroad, who was responsible for the first installations of automatic block signals controlled by track circuits. \u003cbr\u003eAs this memorial would not be complete without a description of the track circuit, its principle and operation under present day signaling practices, Part III is accordingly devoted to this subject. \u003cbr\u003e","brand":"Bronson Tweed Publishing","offers":[{"title":"Default Title","offer_id":47072983941360,"sku":"2940149222605","price":0.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0737\/7593\/9824\/files\/2940149222605_p0.jpg?v=1763714044","url":"https:\/\/shop-qa.barnesandnoble.com\/products\/2940149222605","provider":"Barnes \u0026 Noble (DEV)","version":"1.0","type":"link"}