Treatise on Mathematical Instruments: Their Construction, Adjustment, Testing and Use Concisely ExplainedVirtue Bros. & Company, 1866 - 185 pages |
From inside the book
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Page
... Sextant 104 105 106 112 113 115 117 Artificial Horizon Theodolite 121 122 Surveying , Remarks on Circular Protractor T Square and Semicircular Protractor Plotting Scale of best Form Computation of the Area of a Plot Station Pointer 126 ...
... Sextant 104 105 106 112 113 115 117 Artificial Horizon Theodolite 121 122 Surveying , Remarks on Circular Protractor T Square and Semicircular Protractor Plotting Scale of best Form Computation of the Area of a Plot Station Pointer 126 ...
Page 46
... sextants are now divided at every 10 minutes , and 59 of these parts are made equal to 60 divisions of their verniers ... sextant are double the angles moved over by the in- aex , the limb of the instrument is graduated , as though it ...
... sextants are now divided at every 10 minutes , and 59 of these parts are made equal to 60 divisions of their verniers ... sextant are double the angles moved over by the in- aex , the limb of the instrument is graduated , as though it ...
Page 75
... Sextant , and Troughton's Reflecting Circle , hereafter to be described . Note . - Plane reflectors are usually made of glass silvered at the back ; and , as reflection takes place at each surface of the glass , there is formed a ...
... Sextant , and Troughton's Reflecting Circle , hereafter to be described . Note . - Plane reflectors are usually made of glass silvered at the back ; and , as reflection takes place at each surface of the glass , there is formed a ...
Page 92
... sextant . 4. The theodolite . And under the third , in addition to the instruments already described in Part I. of this Work , we shall say something of- 1. The large circular protractor . 2. The T square and semicircular protractor . 3 ...
... sextant . 4. The theodolite . And under the third , in addition to the instruments already described in Part I. of this Work , we shall say something of- 1. The large circular protractor . 2. The T square and semicircular protractor . 3 ...
Page 117
... SEXTANT . This instrument , which is equally portable with the prismatic compass , forming , when shut up , a box of about three inches in diameter , and an inch and a half deep , will measure the actual angle ... SEXTANT . 117 Box Sextant.
... SEXTANT . This instrument , which is equally portable with the prismatic compass , forming , when shut up , a box of about three inches in diameter , and an inch and a half deep , will measure the actual angle ... SEXTANT . 117 Box Sextant.
Common terms and phrases
accuracy achromatic adjustment altitude axis azimuth beam compasses bisected breadth bubble called chromatic dispersion clamp coincide colatitude compasses construction correct cross wires described diaphragm distinct vision Ditto ditto divided drawing edge equal error extent will reach eye-piece feet figure fixed focal length given number goniometer graduated half horizontal inches index glass instru instrument intersection IVY LANE latitude lens lenses limb line of collimation line of numbers line of sines logarithmic means measured ment meridian microscope number of degrees object-glass observed paper parallax perpendicular placed plane position primary divisions prism protractor quarter girt radius rays reading reflected image reflector refracting refracting telescopes represent right angles right ascension round secants sector sextant side Slide Rule sliding speculum spherical aberration spirit level square staff station subdivisions tangents telescope theodolite transit transverse distance triangle tube turning vernier scale vertical circle zero
Popular passages
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