Treatise on Mathematical Instruments: Their Construction, Adjustment, Testing and Use Concisely ExplainedVirtue Bros. & Company, 1866 - 185 pages |
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Page 7
... less open by means of a mill- headed screw , so as to draw lines of any required fineness or thick- ness . One of the blades is framed with a joint , so that by taking out the screw the blades may be completely opened , and the points ...
... less open by means of a mill- headed screw , so as to draw lines of any required fineness or thick- ness . One of the blades is framed with a joint , so that by taking out the screw the blades may be completely opened , and the points ...
Page 9
... less difficult in their use , and more perfect in the performance of their respec tive operations . " * ON SCALES . Scales of equal parts are used for measuring straight lines , and laying down distances , each part answering for one ...
... less difficult in their use , and more perfect in the performance of their respec tive operations . " * ON SCALES . Scales of equal parts are used for measuring straight lines , and laying down distances , each part answering for one ...
Page 10
... less than tenths of a pri- mary division cannot be accurately taken off from them ; but , by means of a diagonal scale , the parts of any distance which are the hundredths of the primary divisions are correctly in- dicated , as will ...
... less than tenths of a pri- mary division cannot be accurately taken off from them ; but , by means of a diagonal scale , the parts of any distance which are the hundredths of the primary divisions are correctly in- dicated , as will ...
Page 12
... the vernier scale were placed to the left of the zero point , a distance less than one primary division could not always be found upon the scale . cessary , and extend the compasses from the division upon 12 MATHEMATICAL INSTRUMENTS .
... the vernier scale were placed to the left of the zero point , a distance less than one primary division could not always be found upon the scale . cessary , and extend the compasses from the division upon 12 MATHEMATICAL INSTRUMENTS .
Page 19
... less than 45 ° the paral- lels will fall without the primitive , the radii of their projec- tions increasing as the latitude decreases , until the radius for projecting the equator becomes infinite These semi - ellipses may be thus de ...
... less than 45 ° the paral- lels will fall without the primitive , the radii of their projec- tions increasing as the latitude decreases , until the radius for projecting the equator becomes infinite These semi - ellipses may be thus de ...
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Treatise on Mathematical Instruments: Their Construction, Adjustment ... John Fry Heather No preview available - 2016 |
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
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