A Treatise on Mine-surveying |
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Results 1-5 of 68
Page xii
... ground , 226 · Holing from one excavation to another , 228 Sinking shafts from several levels , 232 The cubical content of a mine - reservoir , 233 Determination of the strike and dip of the line of intersection of two veins , 234 The ...
... ground , 226 · Holing from one excavation to another , 228 Sinking shafts from several levels , 232 The cubical content of a mine - reservoir , 233 Determination of the strike and dip of the line of intersection of two veins , 234 The ...
Page 13
... ground is so hard that an arrow cannot be driven in , the leader marks the ground and lays the arrow down . Eleven arrows are usually pre- ferred . The eleventh is used to mark the end of the eleventh chain ; another being substituted ...
... ground is so hard that an arrow cannot be driven in , the leader marks the ground and lays the arrow down . Eleven arrows are usually pre- ferred . The eleventh is used to mark the end of the eleventh chain ; another being substituted ...
Page 15
... ground , may be carried on by half - chains , or even shorter distances . A more accurate method is to measure the angle of the declivity . The cosine of this angle , multiplied by the measured hypothenuse , gives the length of the ...
... ground , may be carried on by half - chains , or even shorter distances . A more accurate method is to measure the angle of the declivity . The cosine of this angle , multiplied by the measured hypothenuse , gives the length of the ...
Page 19
... ground will allow , and as nearly equilateral as possible . The sides of these triangles are first measured , and a straight line is measured from one of the angles to a point in the middle of the opposite side . This fourth line is ...
... ground will allow , and as nearly equilateral as possible . The sides of these triangles are first measured , and a straight line is measured from one of the angles to a point in the middle of the opposite side . This fourth line is ...
Page 20
... ground . The following example shows the manner in which the field- notes may be entered in the survey of a triangular piece of ground : - From B 687 to D , tie - line $ 62 to A From D 956 to D From C 1265 to C 800 to B , point for tie ...
... ground . The following example shows the manner in which the field- notes may be entered in the survey of a triangular piece of ground : - From B 687 to D , tie - line $ 62 to A From D 956 to D From C 1265 to C 800 to B , point for tie ...
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Common terms and phrases
accuracy accurate adjusted back-sight base-line bearing bore-hole brass calculated centre chain City Guilds clamped clinometer coal colliery collimation colour compass compass-box contour lines cord corner cosec cotan cross-wires curve determined direction distance employed equal error fathoms feet fixed fore-sight glass graduated ground height hole horizontal circle inches inches in diameter inclination instrument intersection latitude length lode magnetic bearing magnetic meridian magnetic-needle marked means measured method metres mine-surveying miner's dial mines needle observations obtained offsets Ordnance Survey parallel parallel ruler perpendicular placed plane plate plotting plumb-bob plumb-line plummet position protractor represented right angles safety-lamp scale seam shaft side Silver King spirit-level square staff station station-line strike and dip surface surface-surveys survey tacheometer tacheometry taken tangent screw telescope theodolite transit-theodolite traverse triangle tripod tube underground vernier vernier-plate vertical angles wire yards zero