Treatise on Mathematical Instruments: Their Construction, Adjustment, Testing and Use Concisely ExplainedVirtue Bros. & Company, 1866 - 185 pages |
From inside the book
Results 1-5 of 57
Page 4
... inch radius , and fig . 2 to describe arcs of small radii with exactness by means of the adjusting screw C. For copying and reducing drawings , compasses of a pe- culiar construction are used ; the simplest form of which is that called ...
... inch radius , and fig . 2 to describe arcs of small radii with exactness by means of the adjusting screw C. For copying and reducing drawings , compasses of a pe- culiar construction are used ; the simplest form of which is that called ...
Page 10
... inches , 6 feet 7 inches for instance , extend the compasses from the 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 ...
... inches , 6 feet 7 inches for instance , extend the compasses from the 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 ...
Page 11
... inches in length . In one , the distances between 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 ...
... inches in length . In one , the distances between 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 ...
Page 12
... inch , and , consequently , the distances be- tween the subdivisions are each one - tenth of an ach , and the distances between the divisions of the vernier scale each one - tenth and one - hundredth of an inch . To take off the number ...
... inch , and , consequently , the distances be- tween the subdivisions are each one - tenth of an ach , and the distances between the divisions of the vernier scale each one - tenth and one - hundredth of an inch . To take off the number ...
Page 14
... inches are divided into tenths , as in the scale described in the text , and 100 of these tenths are divided into 100 parts for the vernier scale . * We give the constructions in the text to show the nature of the scales ; but in ...
... inches are divided into tenths , as in the scale described in the text , and 100 of these tenths are divided into 100 parts for the vernier scale . * We give the constructions in the text to show the nature of the scales ; but in ...
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
Page 5 - To which is added, a description of the Principles and Practice of Isometrical Projection. By JF HEATHER, MA -With 14 Plates.
Page 69 - ... that the sine of the angle of refraction bears a constant ratio to the sine of the angle of incidence...
Page 98 - ... of this field of view. We must therefore place some fixed point in the field, of view, and in the focus of the eye-piece, and the point to which the measurement will have reference will be that point of the object viewed, which...
Page 6 - Gd. 131. READY-RECKONER FOR MILLERS, FARMERS, AND MERCHANTS, showing the Value of any Quantity of Corn, with the Approximate Values of Mill-stones & Mill Work.
Page 11 - THE ENTIRE SERIES IS FREELY ILLUSTRATED ON WOOD AND STONE WHERE REQUISITE. The Public are respectfully informed that the whole of the late MB.
Page 5 - Gd. 55. NAVIGATION ; the Sailor's Sea Book : How to Keep the Log and Work it off, &c. ; Law of Storms, and Explanation of Terms, by J. Greenwood. 2s.
Page 24 - From the center at a draw the line ag for the axis of the gnomon agi, and from g let fall the perpendicular gi upon the horizontal meridian line an, and there will be formed a triangle ag i.
Page 143 - ... of them, those which apply to the eye-end of the telescope will answer much better ; the former having their errors magnified by the power of the telescope, will, in proportion to this power, and those errors, be less distinct than the latter. " In taking distances, when the position does not vary from the vertical above thirty or forty degrees, the handles which are attached to the circle are generally most conveniently used ; but in those which incline more to the horizontal, that handle which...
Page 3 - Denison. 3s. 6d. 78. STEAM AND LOCOMOTION, on the Principle of connecting Science with Practice, by J. Sewell. 2s. 78*.