Treatise on Mathematical Instruments: Their Construction, Adjustment, Testing and Use Concisely ExplainedVirtue Bros. & Company, 1866 - 185 pages |
From inside the book
Results 6-10 of 31
Page 45
... exactly equal to the length of a certain number ( n - 1 ) of the divisions upon the limb , and the number ( n ) of divisions upon the vernier being one more than the number upon the same length of the limb . Let , then , L represent the ...
... exactly equal to the length of a certain number ( n - 1 ) of the divisions upon the limb , and the number ( n ) of divisions upon the vernier being one more than the number upon the same length of the limb . Let , then , L represent the ...
Page 46
... exactly coincides with a stroke upon the limb , the reading at this stroke gives the measurement required ; but , if the stroke at the lozenge be a distance . beyond a stroke upon the limb , then will this distance be equal to once , or ...
... exactly coincides with a stroke upon the limb , the reading at this stroke gives the measurement required ; but , if the stroke at the lozenge be a distance . beyond a stroke upon the limb , then will this distance be equal to once , or ...
Page 47
... exactly computed . The instrument having been nearly set by the hand alone , the vernier is fixed in this position by turning a screw , called the clamping screw , which is shown on the top of the vernier in fig . 2 , but is not seen in ...
... exactly computed . The instrument having been nearly set by the hand alone , the vernier is fixed in this position by turning a screw , called the clamping screw , which is shown on the top of the vernier in fig . 2 , but is not seen in ...
Page 49
... exactly coincides with any principal division on the beam , as twelve inches , or six inches , & c . To enable us to do this with extreme accuracy some superior kinds of beam compasses have the box c also furnished with a tangent or ...
... exactly coincides with any principal division on the beam , as twelve inches , or six inches , & c . To enable us to do this with extreme accuracy some superior kinds of beam compasses have the box c also furnished with a tangent or ...
Page 50
... exactly measure that quantity on the detached scale ; then , by loosening the little screws which hold the vernier b in its place , the position of the vernier may be gradually changed , till its zero coincides with the zero on the beam ...
... exactly measure that quantity on the detached scale ; then , by loosening the little screws which hold the vernier b in its place , the position of the vernier may be gradually changed , till its zero coincides with the zero on the beam ...
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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