. Building and repairing railways ... : Forming one of the series of the volumes comprised in the Revised and enlarged edition of The science of railways, . , of course, according to conditions. If the country proposed to be traversed is wellknown and has been settled, accurate maps andsurveys of it can be readily obtained. Accord-ingly, the engineer provides himself with a mapmade preferably on the scale of one inch to amile. Such a map, where a government surveyhas been made, will give the township and sec-tion lines; generally the sub-division of each sec-tion by farm fences enables any des
. Building and repairing railways ... : Forming one of the series of the volumes comprised in the Revised and enlarged edition of The science of railways, . , of course, according to conditions. If the country proposed to be traversed is wellknown and has been settled, accurate maps andsurveys of it can be readily obtained. Accord-ingly, the engineer provides himself with a mapmade preferably on the scale of one inch to amile. Such a map, where a government surveyhas been made, will give the township and sec-tion lines; generally the sub-division of each sec-tion by farm fences enables any desired point tobe accurately located. In cases where the coun- *The dutios and peculiarities of a railway civil engineer arereferred to more fully in the Ijook Railway Organization. THE RECONNOISSANCE. 49 try has not been surveyed by the government, amap or plat will have to be made on a largerscale than that indicated—say two inches to amile, so that the boundaries of farms and otherproperties can be clearly shown. The engineer who makes the reconnoissancewill require the following: an aneroid barome-ter (Figs. 1, 2 and 3), engineers field books and. Fig. 1. Fig. 2. Fig. 3. ANEROID BAROMETER FOR MEASURING ALTITUDES. They indicate the weight or pressure of the atmosphere, from which thealtitude above sea level is determined. note books, drawing paper, a set of pocket in-struments, (Fig. 4); a tin map case or two, a 100ft. steel tape, a prismatic compass (Figs. 5 and6); a hand level (Figs. 7 and 8); a field glass(Fig. 9). Provided with these instruments, theengineer travels the country mostly on foot, lo-cating the controlling points. Upon his map hewill depict not only the location of section lines 4 Vol. 13 50 BUILDING AND REPAIRING RAILWAYS.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectrailroa, bookyear1906
