| Basil Jackson - 1847 - 410 sider
...stations, turn the milled-head, A, until the smallest graduations on the staff can be seen with clearness:* that these two adjustments be very carefully and completely...of more consequence than is generally supposed, for upon them depends the existence or non-existence of instrumental parallax. Having made the above adjustments... | |
| Thomas Baker - 1850 - 244 sider
...cross wires perfectly well defined ; then, directing it to the staff, he must turn the milled headed screw, on the side of the telescope, till he can likewise...depends the existence or non-existence of parallax." " The adjustment of the eye-piece to obtain distinct vision, when once properly made, is not likely... | |
| Sir Henry Edward Landor Thuillier - 1851 - 826 sider
...of the Telescope, till the smallest graduations on the staff are likewise clearly distinguishable, that these two adjustments be very carefully and completely...of more consequence than is generally supposed, for upon them depends the existence or non-existence of parallax to remove which has already been explained... | |
| Frederick Walter Simms - 1856 - 258 sider
...observation in the following order : — First, he must draw out the eye-piece of the telescope till he sees the cross wires perfectly well defined ; then, directing...of more consequence than is generally supposed, for upon them depends the existence or nonexistence of parallax. If any parallax is detected, it must be... | |
| Thomas Baker (Civil engineer) - 1865 - 278 sider
...simple, require great care, otherwise, in extensive works of this kind, errors creep in imperceptibly, to check which the agreement of the differences in...distinguish, with the utmost possible clearness, the smallest gradations on the staff: that these two adjustments be very carefully and completely performed, is... | |
| Frederick Walter Simms - 1870 - 220 sider
...observation in the following order : — First, he must draw out the eye-piece of the telescope till he sees the cross wires perfectly well defined ; then, directing...of more consequence than is generally supposed, for upon them depends the existence or nonexistence of parallax. If any parallax is detected, it must be... | |
| FREDERICK W. SIMMS - 1870 - 174 sider
...observation in the following order :— First, he must draw out the eye-piece of the telescope till he sees the cross wires perfectly well defined ; then, directing...distinguish with the utmost possible clearness the * It must be borne in mind, when we thus minutely detail what may appear to the practical man as naturally... | |
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