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. The railroad and engineering journal . , such as headlands, mountain peaks,etc. Topography on hydrographic charts is generally limitedto as liltle as possible, that part only being topographedwhich will aid the navigator in picking up the land,or in picking out the anchorage. This triangulated shore-line is traced upon chart paper,and we can then proceed with the hydrography of theharbor. Should there be a rise and fall of the tide, then a tidegauge must be established, marked in feet and tenths, andan observer stationed to note and record the height of thewater upon this gauge at different
. The railroad and engineering journal . , such as headlands, mountain peaks,etc. Topography on hydrographic charts is generally limitedto as liltle as possible, that part only being topographedwhich will aid the navigator in picking up the land,or in picking out the anchorage. This triangulated shore-line is traced upon chart paper,and we can then proceed with the hydrography of theharbor. Should there be a rise and fall of the tide, then a tidegauge must be established, marked in feet and tenths, andan observer stationed to note and record the height of thewater upon this gauge at different hours of the day, whilethe sounding parties are at work. The heiglits thus ob-tained enable us to reduce all soundings, taken at variousstages of the tide, to some mean point or common soundings on hydrographic charts are always given,reduced to what they would have been had they all beentaken at mean low water, which signifies the mean/night of all ordinary spring low tides. Vol. LXm, No. 8.] ENGINEERING JOURNAL. 371 I18M1 13.
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectrailroa, bookyear1887