. The sea [microform] : its stirring story of adventure, peril & heroism. Adventure and adventurers; Voyages and travels; Ocean; Aventures et aventuriers; Voyages; Océan. TAKING OBSERVATIONS. r281 's runiuiiff. precisely how far his visual faculties vary from the ideal. Hence arises a question, incom- prehensible to the uninitiated, which, however, is commonly asked among astronomers themselves â' What is the value of your j ersonal equation ?' This inquiry is answered by a figure expressing the particular amount of deviation from the standard. The most singular thing is,. â ; !i THE GREA
. The sea [microform] : its stirring story of adventure, peril & heroism. Adventure and adventurers; Voyages and travels; Ocean; Aventures et aventuriers; Voyages; Océan. TAKING OBSERVATIONS. r281 's runiuiiff. precisely how far his visual faculties vary from the ideal. Hence arises a question, incom- prehensible to the uninitiated, which, however, is commonly asked among astronomers themselves â' What is the value of your j ersonal equation ?' This inquiry is answered by a figure expressing the particular amount of deviation from the standard. The most singular thing is,. â ; !i THE GREAT EQUATORIAL TELESCOPE IN THE DOME, GREENWICH 0B8EKVATOBY. that the value of the personal equation is different in the same individual as regards the various celestial bodies. Some can very quickly discern the phenomena of a fixed star who are much slower in perceiving those of the moon, and vice versd. In order to obviate the inconvenience which might result from the variations in jwrsonal equations, they also have recourse to a very ingenious plan. An eye-piece with two tubes allows two assistants simul- taneously to observe the passage of the same star over the same threads in the instrument; 156. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Whymper, Frederick, b. 1838. London; New York : Cassel, Petter, Galpin
Size: 1582px × 1580px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, booksubjectocean, booksubjectvoyagesandtravels
