| Thomas Keith - 1810 - 420 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 - 442 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 - 500 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 - 200 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
...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... | |
| |