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 8
... exactly , than a straight or any other line , though even then many difficulties occur , when the circle is required to be of a large radius . " And let no one consider these reflections as the effect of too scrupulous exactness , or as ...
... exactly , than a straight or any other line , though even then many difficulties occur , when the circle is required to be of a large radius . " And let no one consider these reflections as the effect of too scrupulous exactness , or as ...
Page 13
... exactly correspond , unless this scale has been first laid down upon the paper itself , and all the divisions have been taken from the scale so laid down , which is always in the same state of expansion as the plot . For plotting , then ...
... exactly correspond , unless this scale has been first laid down upon the paper itself , and all the divisions have been taken from the scale so laid down , which is always in the same state of expansion as the plot . For plotting , then ...
Page 26
... exactly equal to the length of twenty of the primary divisions of the diagonal or vernier scale , or of the beam compasses ( p . 48 ) , by which it is to be divided , bisect it , and figure it 1 at the commencement on the left hand , 1 ...
... exactly equal to the length of twenty of the primary divisions of the diagonal or vernier scale , or of the beam compasses ( p . 48 ) , by which it is to be divided , bisect it , and figure it 1 at the commencement on the left hand , 1 ...
Page 36
... exactly the same . USES OF THE LINE OF LINES . To find a Fourth Proportional to three given Lines . - Set off from the center a lateral distance equal to the first term , and open the sector till the transverse distance at the division ...
... exactly the same . USES OF THE LINE OF LINES . To find a Fourth Proportional to three given Lines . - Set off from the center a lateral distance equal to the first term , and open the sector till the transverse distance at the division ...
Page 40
... exactly divide 360 ( the number of degrees into which all circles are supposed to be divided ) without a remainder , may likewise be set off upon the circumference of a circle by the line of chords Thus , take the radius of the circle ...
... exactly divide 360 ( the number of degrees into which all circles are supposed to be divided ) without a remainder , may likewise be set off upon the circumference of a circle by the line of chords Thus , take the radius of the circle ...
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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