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 50
Page 4
... given line , the shorter ones will be opened to the half of that line . By their means , then , all the lines of a drawing may be reduced to one - half , or enlarged to double their length . These com- passes are also useful for ...
... given line , the shorter ones will be opened to the half of that line . By their means , then , all the lines of a drawing may be reduced to one - half , or enlarged to double their length . These com- passes are also useful for ...
Page 6
... given by the distance of the points D and E when the line is set to 3 , the respective distances of the points will give the like sides of solids , the contents of which will be in the proportion of 3 to 1 ; and so on . The Cube Root of ...
... given by the distance of the points D and E when the line is set to 3 , the respective distances of the points will give the like sides of solids , the contents of which will be in the proportion of 3 to 1 ; and so on . The Cube Root of ...
Page 17
... given meridian and parallel of latitude . The plane upon which the circles are to be delineated is called the primitive , and the circumference of a circle , de- scribed with a radius , representing , upon the reduced scale of the ...
... given meridian and parallel of latitude . The plane upon which the circles are to be delineated is called the primitive , and the circumference of a circle , de- scribed with a radius , representing , upon the reduced scale of the ...
Page 21
... given lati- tude , take the difference of the complement of the given lati- tude and of the colatitude of the place from the line of semi- tangents , and , having reduced it to the radius of the primitive , set it off at r from c ...
... given lati- tude , take the difference of the complement of the given lati- tude and of the colatitude of the place from the line of semi- tangents , and , having reduced it to the radius of the primitive , set it off at r from c ...
Page 28
... given to be multiplied by 250 , extend the compasses from 1 at the left hand to midway between the second and third sub- division , in the first primary division from 1 to 2 , for the 125. This extent is really the logarithm of 1.25 ...
... given to be multiplied by 250 , extend the compasses from 1 at the left hand to midway between the second and third sub- division , in the first primary division from 1 to 2 , for the 125. This extent is really the logarithm of 1.25 ...
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*.