A Treatise on Surveying, Volume 2Spon, 1902 |
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Results 1-5 of 68
Page xi
... Circle , Azimuth , and Bearings 87 Computations 88 • Spherical Excess . 89 . Law of Convergence • • 225 92 93 Example in difference of Plane and Spherical Computations Convergence of Meridians discussed 97 Examples in Convergence • 98 ...
... Circle , Azimuth , and Bearings 87 Computations 88 • Spherical Excess . 89 . Law of Convergence • • 225 92 93 Example in difference of Plane and Spherical Computations Convergence of Meridians discussed 97 Examples in Convergence • 98 ...
Page 7
... circle to a given radius . There are two kinds of planimeters in general use . ( 1 ) The fixed planimeter , which works to one scale only , reading in square inches , and is most useful for measuring the area of indicator diagrams . ( 2 ) ...
... circle to a given radius . There are two kinds of planimeters in general use . ( 1 ) The fixed planimeter , which works to one scale only , reading in square inches , and is most useful for measuring the area of indicator diagrams . ( 2 ) ...
Page 15
... circle , index and collimation errors are elimi- nated by reversing the telescope , between each pair of readings , and taking half the readings with circle ( or face ) right ' and half with ' circle ( or face ) left . ' 7. It is not ...
... circle , index and collimation errors are elimi- nated by reversing the telescope , between each pair of readings , and taking half the readings with circle ( or face ) right ' and half with ' circle ( or face ) left . ' 7. It is not ...
Page 16
... circle , and noting the number of seconds on the circle corresponding to a motion ( of the circle and level together ) which carries the bubble over a given number of divisions . Thus , suppose we read the O and E ends of a level thus ...
... circle , and noting the number of seconds on the circle corresponding to a motion ( of the circle and level together ) which carries the bubble over a given number of divisions . Thus , suppose we read the O and E ends of a level thus ...
Page 17
... circle belonging to a separate instrument : - - Direct the telescope on a distant but well - defined object . Clamp the vertical circle , and read both ends of the bubble and the vertical circle . By one of the foot - screws , elevate ...
... circle belonging to a separate instrument : - - Direct the telescope on a distant but well - defined object . Clamp the vertical circle , and read both ends of the bubble and the vertical circle . By one of the foot - screws , elevate ...
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Common terms and phrases
accuracy accurate astronomical azimuth barometer base C₁ calculated celestial celestial pole celestial sphere centre Chron chronometer circle computation convergence Corr correction curve declination deducting determined dial difference earth equal equator error feet fixed stars float formula gauge given Greenwich Greenwich mean height high water horizontal hour angle hypsometer inches instant instrument intersection interval latitude length longitude low water lunar mark mean noon measured meridian altitude method miles moon nautical notch obsn obtained parallel perpendicular place of observation plane plane-table plotted point of Aries position prime vertical projection radius readings refraction right angles right ascension scale sea level sextant side sidereal sin² solar sphere spherical triangle spherical trigonometry staff Star's stations stream subtended sun's surface survey surveyor taken tangent tangential angle telescope theodolite Therm tide tide-gauge transit velocity vide fig wire zenith distance
Popular passages
Page 87 - The longitude of a place is the arc of the equator intercepted between the meridian of that place and some assumed meridian to which all others are referred.
Page 145 - Ocean, the first thing which strikes us is, that, the north-east and south-east monsoons, which are found the one on the north and the other on...
Page 134 - ... the column directs the manner in which it is to be applied to mean time to obtain the apparent time. The equation of time, as given on page II, is the apparent time of mean noon; and is equivalent to the hour-angle of the true sun at the instant of mean noon. The sidereal time of mean noon is also the right ascension of the mean sun at Greenwich mean noon.
Page 59 - In any equiangular polygon, any interior angle is equal to twice as many right angles as the figure has sides, less four right angles, divided by the number of angles.
Page 77 - A, 4 cos 6 = cos c cos a + sin c sin a cos B, > (1) . , "cos c = cos a cos b + sin a sin b cos C. J Whence . cos a — cos b...
Page 14 - ... by moving the telescope vertically, and read the two ends. Read the height of the crosswires on the rod. Bring the bubble near the other end of tube and read both the bubble and rod. Repeat many times. Reduce the work by taking the half-difference of the two end readings in each case, thus giving the distance of the centre of the bubble from the centre of tube for each position. Take the mean of these results for each set of end readings separately. If these mean results were for opposite ends...
Page 42 - Where each day's work left off, a fine plumb-line was suspended to mark it off, the plummet vibrating in a brass cup, sunk in the ground and filled with water.
Page 76 - That is, the sines of the sides of a spherical triangle are proportional to the sines of the opposite angles.
Page 125 - Napier has there given a figure, and indicated a method, by means of which they may be proved directly. The rules are curious and interesting, but of very doubtful utility...
Page 7 - ... the plane of the sextant. The simplest test of its perpendicularity is the following. Set the index near the middle of the arc; then, placing the eye very nearly in the plane of the sextant, and near the index glass, observe whether the arc seen directly and its reflected image in the glass appear to form one continuous arc, which will be the case only when the glass is perpendicular.