 | Thomas Keith - 1810 - 478 pages
...these equals take the /»p£,then /cf-/*sA— ZEP£=/»ZSP + /£FS the sum of the two refractions; that is, subtract the depression from the sum of the contained arc and elevation, and half the remainder is the mean refraction. Perhaps it may be necessary to remark, that... | |
 | Thomas Keith - 1826 - 504 pages
...the L BP¿, then ¿_ e -f- L esA — L BPÜ>= Z. msp + L OPS the sum of the two refractions ; that is, subtract the depression from the sum of the contained arc and elevation, and half the remainder is the mean refraction. Perhaps it may be accessary to remark, that... | |
 | Thomas Keith - 1839 - 498 pages
...equals take the L BP&, then the sum of the two refractions L msp + L SPS= L c + L esA — L BP£ ; that is, subtract the depression from the sum of the contained arc and elevation, and half the remainder is the mean refraction. Perhaps it may be necessary to remark, that... | |
 | Edward Charles Frome - 1840 - 232 pages
...365,110 feet, or 69.15 miles— and one second=101.42 feet. the sum of the two angles, eAB and EBA, will be greater than EAB + EBA (the angle C, or the...station on Allington Knoll, known to be 329 feet above low-water, f the top of the staff on Tenterden steeple was depressed by observation 3' 51", and the... | |
 | John Gregory - 1843 - 350 pages
...refraction. If one of the points, B, be elevated to the point g, instead of being depressed, then the rule is, subtract the depression from the sum of the contained...and half the remainder is the mean refraction. The angles should be taken simultaneously by means of signals, or by watches previously regulated for the... | |
 | P. O'Shaughnessy (Civil engineer) - 1848 - 110 pages
...if the point B, be elevated to the point X, instead of being depressed, then the rule is, substract the depression from the sum of the contained arc,...and half the remainder is the mean refraction. The angles should be taken at the same time. The amount of refraction found by these rules must be substracted... | |
 | Anthony Nesbit - 1859 - 482 pages
...these equals take the Z BPi, then the sum of the two refractions /_m$P+ /_bPS= ZC+ZeSA— ZBP6; that is, subtract the depression from the sum of the contained arc and elevation, and half the remainder is the mean refraction. Perhaps it may be necessary to remark, that... | |
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BA, the sum of the two refractions ; the rule for the mean refraction then in this case is, subtract the depression from the sum of the contained arc and the elevation, and half the remainder is the mean refraction -. The... 