 | Frederick Walter Simms - 1834 - 124 pages
...parallel to each other when the index division of the vernier is at 0° on the arc, and the optical axis of the telescope must be parallel to the plane of the instrument. We shall speak separately of eaeh of these adjustments. To examine Ike. Adjustment, of... | |
 | Basil Jackson - 1847 - 410 pages
...parallel to each other, when the index division of the vernier is at 0° on the arc ; and the optical axis of the telescope must be parallel to the plane of the instrument. We shall speak separately of each of these adjustments. TO EXAMINE THE ADJUSTMENT OF THE... | |
 | Benjamin Pike (Jr.) - 1848 - 482 pages
...parallel to each other when the index division of the vernier is at 0° on the arc, and the optical axis of the telescope must be parallel to the plane of the instrument. We shall speak separately of each of these adjustments. To examine the adjustment of the... | |
 | Benjamin Pike - 1848 - 356 pages
...parallel to each other when the index division of the vernier is at 0° on the arc, and the optical axis of the telescope must be parallel to the plane of the instrument. We shall speak separately of each of these adjustments. To examine the adjustment of the... | |
 | Sir Henry Edward Landor Thuillier - 1851 - 826 pages
...parallel to each other when the index division of the vernier is at 0° on the arc, and the optical axis of the telescope must be parallel to the plane of the instrument. We shall speak separately of each of these adjustments. "*" To examine the Adjustment of... | |
 | W. Davis Haskoll - 1858 - 422 pages
...must be parallel to each other when the zero of the vernier is set to zero on the limb. The optical axis of the telescope must be parallel to the plane of the instrument. To test the perpendicularity of the index glass. Slide the index to about 40° or 45°... | |
 | Thomas Liddell Ainsley - 1864 - 360 pages
...the same straight line. Then will the horizon-glass be truly parallel to the index-glass. 4¿A. The axis of the telescope must be parallel to the plane of the instrument. Turn the eye-piece of the telescope till two of the parallel wires in its focus appear... | |
 | Thomas Liddell Ainsley - 1875 - 416 pages
...itself, which can be turned by placing a capstan-pin into the hole in the head of the screw. yd. The axis of the telescope must be parallel to the plane of the instrument.* — Turn the eye-piece of the telescope till two of the parallel wires in its focus appear... | |
 | 1880 - 880 pages
...telescope parallel to the plane of the sextant. In measuring angular distances, the line of sight, or axis of the telescope, must be parallel to the plane of the instrument, as a deviation in that respect, ¡u measuring large angles, will occasion a considerable... | |
 | Charles Leander Doolittle - 1885 - 666 pages
...necessary correction to the angles measured, as will be explained hereafter. 108. Third Adjustment. The axis of the telescope must be parallel to the plane of the instrument. Two parallel threads are placed in the eye-piece to mark approximately the middle of the... | |
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THE requisite adjustments are the following : the index and horizon-glasses must be perpendicular to the plane of the instrument, and their planes parallel to each other when the index division of the vernier is at 0° on the arc, and the optical axis... 
