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 9
... division on the left hand . The first of these primary divisions is sub- divided into ten equal parts , and from these last divisions the scale is named . Thus it is called a scale of 30 , when 30 of these small parts are equal to one ...
... division on the left hand . The first of these primary divisions is sub- divided into ten equal parts , and from these last divisions the scale is named . Thus it is called a scale of 30 , when 30 of these small parts are equal to one ...
Page 10
... primary division numbered 6 , to the 7th upper subdivision , reckoning back- wards , as before . Diagonal Scales . - In the simply - divided scales one of the primary divisions is subdivided only into ten equal parts , and the parts of ...
... primary division numbered 6 , to the 7th upper subdivision , reckoning back- wards , as before . Diagonal Scales . - In the simply - divided scales one of the primary divisions is subdivided only into ten equal parts , and the parts of ...
Page 11
... primary divisions are each half an inch , and in the other a quarter of an inch . The parallel next to the figures numbering these divisions must be considered the highest or first parallel in each of these scales to accord with the ...
... primary divisions are each half an inch , and in the other a quarter of an inch . The parallel next to the figures numbering these divisions must be considered the highest or first parallel in each of these scales to accord with the ...
Page 12
... primary division , and it will reach beyond the beginning of this division , or zero point , a distance equal to one of the sub- divisions . Now divide the extent thus set off into ten equal parts , marking the divisions on the opposite ...
... primary division , and it will reach beyond the beginning of this division , or zero point , a distance equal to one of the sub- divisions . Now divide the extent thus set off into ten equal parts , marking the divisions on the opposite ...
Page 13
... primary division , unless these divisions be themselves very small . We are not aware that a scale of this kind has been put upon the plain scales sold by any of the instrument makers ; but , during the time occupied in plotting an ...
... primary division , unless these divisions be themselves very small . We are not aware that a scale of this kind has been put upon the plain scales sold by any of the instrument makers ; but , during the time occupied in plotting an ...
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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