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Fig. 67

PLATE XXII

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N.G.C. II 4997; 20h 15m6; +16° 25'

Exposures 10 to 1". About magn. 10. Indistinguishable from a star on the Crossley negatives, but shown to have a minute disk visually with the 36-inch refractor. Scale, 1 inch = 7.5.

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Fig. 69

Fig. 70

Fig. 71

N.G.C. 6905; 20h 17m9; +19° 47' Exposures 5 to 3h. H.C.O. magn. 10.8 (total effect?). The central star is 14th magn. visually (Burnham) and 13th or brighter photographically. The main portion is a very patchy truncated ellipse 44" 37" in p. a. 163°. Very faint cone-shaped ansac extend from each end. A star of magn. 12 lies nearly at the end of the southern ansa (not shown in drawing), but is probably not physically connected with the planetary. Moderately faint; the nebular matter just shows in 5m on S23. Rel. Exp. 20.

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N.G.C. 7008; 20h 57m6; +54° 9'

Enlarged 11 times from a negative of 2h 30m exposure time. Central star magn. 12. Irregular ring structure indicated; the dimensions are 86" X 69" in p. a. 20°. The two brightest patches are at the north, and three stars which lie in roughly circular gaps in the nebulosity must either be physically connected with the nebula or, if nearer to us, be surrounded by absorbing atmospheres. Moderately faint. Rel. Exp. 20.

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N.G.C. 7009; 20h 58m7; -11° 46

Exposures 10 to 2h. Central star of magn. 11 (Burnham, 12 visual). Of wonderfully intricate structure; the slightly oval central disk is about 30" x 26", while the almost stellar condensations at the ends of the ansae are 44" apart in p. a. 79°. The inner ring shows considerable detail in the shortest exposures; in moderate exposures it is 25" X 12", and slightly fainter along its major axis. Exceedingly bright; the nucleus and inner ring show in 10% on $27. Rel. Exp. 0.2.

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N.G.C. 7026; 21h 2m9; +47° 27'

Exposures 30% to 2h 10m. H.C.O. 11.4 magn. Central star of mag. Very irregular; there are two bright lobes 5" long in the shorter exposure's symmetrically placed with regard to the central star, and about 6" apart from center to center. A bridge of nebulosity connects these and involves the central star, so that it resembles the letter H. Irregular wisps extend from each end of this formation, making the total length about 25" in p. a. about 10°. Fairly bright; the lobes show in 1" on S27. Rel. Exp. 0.8.

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N.G.C. 7027; 21" 3m3; +41° 50'

Exposures 5 to 2h. H.C.O. magn. 9.0. The condensations are not stellar in the shortest exposures. Quite irregular, and roughly trinuclear, though the southern condensation is apparently composed of two masses close together. The southern condensation and the brighter at the north are 7.5" apart in p. a. 135°. 1 exposure on S23 shows an irregular oblong 18" X 11", with central details entirely "burnt out." Exceedingly bright; 30s on S23 shows all the central features. Rel. Exp. 0.1.

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N.G.C. II 5117; 21h 28m6; +44° 10'

Exposures 20 to 40m. Magn. 10. Indistinguishable from a star on the Crossley negatives, but shown to have a minute disk visually with the 36-inch refractor. Scale, 1 inch = 75.

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N.G.C. 7139; 21h 43m5; +63° 19'

Exposure 2. The central star is magn. 18. The oval is 86" X 67", in p. a. 20°. Considerably fainter along the major axis; at the east and west edges slightly brighter streaks appear, indicating a ring or shell formation. Exceedingly faint. Rel. Exp. 300.

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N.G.C. II 5217; 22h 19m9; +50° 28'

Exposures 10 to 1". H.C.O. magn. 11.1. No central star can be distinguished. A bright oval about 7.5" X 6" in a 5 exposure; slightly larger and quite square-shouldered" in the long exposure. Brighter along the middle, but no details of structure can be made out. Very bright; shows well in 1" on S23. Rel. Exp. 0.2.

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