| Jabez Hogg - 1867 - 1456 pages
...if opaque. Remove A, and open the slit by means of the milled-head, not shown in cut, but which is at right angles to D D. When the slit is sufficiently...gradually close the slit till a good spectrum is obtained. The spectrum will be much improved by throwing the object a little out of focus. Every part of the... | |
| Henry E. Roscoe - 1869 - 372 pages
...bull's eye, &c. Eemove a, and open the slit by means of the milled head, not shown in cut, but which is at right angles to d d. "When the slit is sufficiently...gradually close the slit till a good spectrum is obtained. The spectrum will be much improved by throwing the object a little out of focus. Every part of the... | |
| Henry Enfield Roscoe - 1870 - 514 pages
...bull's-eye, &c. Remove a, and open the slit by means of the milled head, not shown in cut, but which is at right angles to d d. When the slit is sufficiently...gradually close the slit till a good spectrum is obtained. The spectrum will be much improved by throwing the object a little out of focus. Every part of the... | |
| sir Henry Enfield Roscoe - 1869 - 396 pages
...and open the slit by means of the milled head, not shown in cut, but which is at right angles to dd. When the slit is sufficiently open, the rest of the...gradually close the slit till a good spectrum is obtained. The spectrum will be much improved by throwing the object a little out of focus. Every part of the... | |
| John Henry Pepper - 1869 - 722 pages
...and open the slit by means of the milled head, not shown in cut, but which is at right angles to I' D. When the slit is sufficiently open, the rest of...like an ordinary eye-piece, and any object can be focused in the usual way. Having focused the object, replace A, and gradually close the slit till a... | |
| sir Henry Enfield Roscoe - 1870 - 452 pages
...bull-s-eye, &c. Remove a, and open the slit by means of the milled head, not shown in cut, but which is at right angles to d d. When the slit is sufficiently...acts like an ordinary eyepiece, and any object can lie focussed in the usual way. Having focussed the object, replace a, and gradually close the slit... | |
| sir Henry Enfield Roscoe - 1873 - 550 pages
...bull's-eye, &c. Remove a, and open the slit by means of the milled head, not shown in cut, but which is at right angles to d d. When the slit is sufficiently...gradually close the slit till a good spectrum is obtained. The spectrum will be much improved by throwing the object a little out of focus. out by accurately... | |
| Henry Enfield Roscoe - 1873 - 542 pages
...and open the slit by means of the milled head, not shown in cut, but which is at right angles to dd. When the slit is sufficiently open, the rest of the...gradually close the slit till a good spectrum is obtained. The spectrum will be much improved by throwing the object a little out of focus. Every part of the... | |
| John Henry Pepper - 1877 - 764 pages
...bull's-eye, &c. Remove A, and open the slit by means of the milled head, not shown in cut, but which is at right angles to D D. When the slit is sufficiently...like an ordinary eye-piece, and any object can be focused in the usual way. Having focused the object, replace A, and gradually close the slit till a... | |
| John Browning (F.R.A.S.) - 1878 - 80 pages
...opaque, or by side reflector, bull's-eye, &c. Remove A, and open the slit by means of the milled head, H, at right angles to D D. When the slit is sufficiently...gradually close the slit till a good spectrum is obtained. The spectrum will be much improved by throwing the object a little out of focus. Every part of the... | |
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