. Appendix to Captain Parry's journal of a second voyage [microform] : for the discovery of a north-west passage from the Atlantic to the Pacific, performed in His Majesty's ships Fury and Hecla in the years 1821-22-23. Science; Botany; Sciences; Botanique. Mil. FISHER ON ATMOSPHERICAL REFRACTION. 17;J It and also the care that was taken by him to determino its error. The latitude o! the ship by which his observations were computed was 69° '20' 41" N., determined trigonometrically from the latitude of the observatory, agreeing within two seconds with that determined by himself, by near on
. Appendix to Captain Parry's journal of a second voyage [microform] : for the discovery of a north-west passage from the Atlantic to the Pacific, performed in His Majesty's ships Fury and Hecla in the years 1821-22-23. Science; Botany; Sciences; Botanique. Mil. FISHER ON ATMOSPHERICAL REFRACTION. 17;J It and also the care that was taken by him to determino its error. The latitude o! the ship by which his observations were computed was 69° '20' 41" N., determined trigonometrically from the latitude of the observatory, agreeing within two seconds with that determined by himself, by near one hundred observations, with an eight-inch sextant, by Troughton, and false horizon. A comparison of the zenith distances of different objects, with this instrument and the repeating circle, at the same time and place, assign an error to this instrument a little different, and which if applied to his observations would make them agree nearly with my own; but in order that his observations should be as in. dependent of my own as possible, his own error has been applied. The greatest part of the observations made with the sextants and the altitude instrument, were confined to altitudes not exceeding four or five degrees. And in all the observations made out of the meridian, whether made with sext&..it or repeating circle, the altitudes were also within the same limits; those at higher altitudes were entirely confined to observation in the meridian with the repeating circle, with not less than six or eight repetitions each. There arc some circumstances which rendered the usual sources of inaccuracy attached to this method of determining the refraction by observations out of the meridian within very narrow limits, which were, first, from the high latitude of the place of observation, and from the greater part of the observations being taken near the meridian, the motion in altitude was therefore bo slow, that an error of three or four seconds in time would cause but a very sma
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Keywords: ., bookcentury1800, booksubjectbotany, booksubjectscience, bookyear1
