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 49
... carries after ad- justment to position . F is a slow motion screw , by which the point & may be moved any very minute quantity for perfecting the setting of the instrument , after it has been otherwise set as nearly as possible by the ...
... carries after ad- justment to position . F is a slow motion screw , by which the point & may be moved any very minute quantity for perfecting the setting of the instrument , after it has been otherwise set as nearly as possible by the ...
Page 97
... , resting upon two supporters , which in shape resemble the letter Y , and are consequently called the Ys . The lower ends of these supporters are let perpendicu- F larly into a strong bar , which carries a compass THE Y LEVEL . 97 Y Level.
... , resting upon two supporters , which in shape resemble the letter Y , and are consequently called the Ys . The lower ends of these supporters are let perpendicu- F larly into a strong bar , which carries a compass THE Y LEVEL . 97 Y Level.
Page 98
... carries a compass box c . This compass box is convenient for taking bearings , and has E B a contrivance for throwing the needle off its cen- ter , when not in use . One of the Y supporters is fitted into a socket , and can be raised or ...
... carries a compass box c . This compass box is convenient for taking bearings , and has E B a contrivance for throwing the needle off its cen- ter , when not in use . One of the Y supporters is fitted into a socket , and can be raised or ...
Page 102
... carries the diaphragm with the cross wires . If this perfection in the construction of the in- strument does not exist , the line of collimation will vary , as the tube carrying the object - glass is thrust out , and drawn in , to ...
... carries the diaphragm with the cross wires . If this perfection in the construction of the in- strument does not exist , the line of collimation will vary , as the tube carrying the object - glass is thrust out , and drawn in , to ...
Page 124
... carries two Ys for supporting the telescope , which is of the same construction as that before described for the Y spirit level , and under- neath the telescope is a spirit level , s s , attached to it at one end by a joint , and at the ...
... carries two Ys for supporting the telescope , which is of the same construction as that before described for the Y spirit level , and under- neath the telescope is a spirit level , s s , attached to it at one end by a joint , and at the ...
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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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