A description of the dipleidoscope, or double-reflecting meridian and altitude instrument : with plain instructions for the method of using it in the correction of time-keepers / by Edward J. Dent.

Edward John Dent

Date:: 1845

Credit: A description of the dipleidoscope, or double-reflecting meridian and altitude instrument : with plain instructions for the method of using it in the correction of time-keepers / by Edward J. Dent. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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$DENT’S TABLE FOR THE _ To accompany his New This Table shows the Time which a Clock or Watch should indicate when the Sun is on the meridian, and the difference is its error. THIS TABLE IS DEDUCED FROM THE NAUTICAL Day of Month January, Fkbruary. March. April. May. • June. H. M. s. H. M. s. H. M. s. H. M. s. H. M. s. H. M. s. 1 12 3 56-9 12 13 55-9 12 12 34.7 12 3 56-2 11 56 56.7 11 57 28.7 1 2 4 25-1 99 14 3-2 99 12 22-4 99 3 38.1 19 56 49.4 99 57 37-9 j 3 4 530 99 14 9-8 99 12 9.7 99 3 20.1 99 56 42.7 99 57 47.5 1 4 5 20-4 99 14 15-6 99 11 56.6 99 3 2-3 99 56 366 99 57 o/.o I 5 5 47-5 99 14 20-5 99 11 43.0 99 2 44.7 99 56 311 >9 58 7.8 i 6 6 14.1 >9 14 24-6 99 11 28.9 99 2 27.2 99 56 26-1 99 58 18.4 7 6 40-2 99 14 280 99 11. 14.5 99 2 10.0 99 56 21.6 99 58 29.4 8 7 5-9 J> 14 30-5 99 10 59.7 99 1 53.0 99 56 17.8 99 58 40.7 9 7 31-0 99 14 32-3 99 10 44.5 99 1 36.2 99 56 14-5 99 58 52.2 10 99 7 55-6 99 14 33-2 99 10 28.9 99 1 19.7 99 56 11-7 99 59 3-91 11 99 8 19-5 99 14 33-4 99 10 130 99 1 3-4 99 56 9-6 99 59 .15-9ij 12 99 8 42-9 99 14 32-7 99 9 56-8 99 0 47-4 99 56 7-9 99 59 28.0 i 13 99 9 5-6 99 14. 313 » 9 40-3 99 0 31-7 99 56 6-9 >1 59 40-3 il 14 99 9 27-6 99 14 29-1 99 9 23.5 99 0 163 99 56 6.4 99 59 52.8 \ 15 99 9 49*0 99 14 26-2 99 9 6-4 99 0 1-2 99 56 6.4 12 0 531 16 99 10 9-6- 99 14 22.5 11 8 49-1 11 59 46»5 11 56 70 19 0 18<0| 17 99 10 29-6 99 14 18.1 11 8 31.5 99 59 32.1 11 56 8-2 11 0 30.7 i 18 99 10 48-8 99 14 130 11 8 13.8 99 59 18.1 11 56 9.9 19 0 43.6^ 19 99 11 7-2 99 14 7.2 11 7 55-8 99 59 4.4 11 56 12.1 99 0 56.4 i| 20 99 11 24-9 99 14 0.7 11 7 37.7 >9 58 51.*2 11 56 14.9 99 1 9.31 21 J9 11 41-9 19 13 535 11 7 195 99 58 38-4 11 56 18.2 99 1 222] 22 29 11 58-0 99 13 45.7 11 7 1.1 99 58 26.0 11 56 22.1 99 1 35.0] 23 29 12 13-4 99 13 37.3 11 6 42-6 99 58 141 11 56 26.5 99 1 47.9] 24 12 28-0 99 13 28.2 11 6 24-1 99 58 2-6 11 56 31-4 99 2 oe] 25 99 12 41-7 99 13 18-6 11 6 5-5 99 57 51.7 11 56 36-8 99 2 13.3I 26 12 54-7 99 13 8-4 11 5 46-9 99 57 -fl.2 99 56 42.8 99 2 26.0I 27 99 13 6-9 99 12 57.7 11 5 28-3 99 57 31.2 99 56 49-2 99 2 38.4I 28 99 13 18-3 99 12 46.5 11 5 9.8 99 57 21.8 99 56 562 99 2 50.d 29 99 13 28-9 99 4 51.3 99 57 12.9 99 57 3.6 99 3 2.9I 30 99 13 38-7 99 4 32.8 99 57 4-5 99 57 11.5 99 3 14.9I 31 99 13 47-7 99 4 14.5 99 57 199$