Historical Identification: Per Dreyer, IC 2100 (Bigourdan #380, Roberts, 1860 RA 04 44 20, NPD 95 04.3) is "very faint, small, a little extended, stellar."
Physical Information:

Historical Identification: Per Dreyer, IC 2101 (Roberts, 1860 RA 04 44 51, NPD 96 28.2) is "faint, extended north-preceding south-following (northwest-southeast), brighter middle, probably spiral."
Physical Information: Apparent size 1.7 by 0.4 arcmin?

Historical Identification: Per Dreyer, IC 2102 (Roberts, 1860 RA 04 44 58, NPD 95 12.7) is "very faint, a little brighter middle, probably spiral."
Physical Information: Apparent size 1.2 by 0.9 arcmin?

Historical Identification: Per Dreyer, IC 2103 (DeLisle Stewart #300, 1860 RA 04 45 00, NPD 167 05) is "considerably faint, very small, extremely extended 80°, stellar nucleus."
Physical Information: Apparent size 1.8 by 0.3 arcmin?

Historical Identification: Per Dreyer, IC 2104 (Barnard, 1860 RA 04 50 00, NPD 106 01.2) is "faint, extended, gradually brighter middle."
Physical Information: Apparent size 2.5 by 1.1 arcmin?

Historical Identification: Per Dreyer, IC 2105 (Fleming #84, 1860 RA 04 50 06, NPD 159 25) is "planetary, stellar."
Physical Information: Apparent size 0.7 by 0.5 arcmin.

Historical Identification: Per Dreyer, IC 2106 (Swift list XI (#73), 1860 RA 04 50 25, NPD 118 45.5) is "most extremely faint, pretty large, double star 24 seconds of time following (to the east)."
Physical Information: Apparent size 1.7 by 0.9 arcmin?

Historical Identification: Per Dreyer, IC 2107 (Bigourdan #381, 1860 RA 04 50 45, NPD 81 59) is "a cluster, very faint, very small, round."
Physical Information: This entry will be primarily concerned with historical information; for anything else see NGC 1707.

Historical Identification: Per Dreyer, IC 2108 (Bigourdan #261, 1860 RA 04 50 56, NPD 105 31) is "very faint, pretty small, round, much brighter middle, 9.5 magnitude star 1.3 arcmin south-following (to the southeast)."
Physical Information: This entry will be primarily concerned with historical information; for anything else see NGC 1710.

Historical Identification: Per Dreyer, IC 2109 (Bigourdan #382, 1860 RA 04 51 51, NPD 90 32) is "a very faint star, perhaps nebulous?"
Physical Information:

Historical Identification: Per Dreyer, IC 2110 (Bigourdan #383, 1860 RA 04 51 54, NPD 90 32) is "a very faint star, perhaps nebulous?"
Physical Information:

Historical Identification: Per Dreyer, IC 2111 (Fleming #85, 1860 RA 04 52 50, NPD 159 37) is "planetary, stellar."
Physical Information:

Historical Identification: Per Dreyer, IC 2112 (Javelle #989, 1860 RA 04 53 06, NPD 85 48.5) is "very faint, pretty small, diffuse."
Physical Information: Apparent size 0.5 by 0.2 arcmin?

Historical Identification: Per Dreyer, IC 2113 (Barnard, 1860 RA 04 53 12, NPD 106 02.2) has "no description."
Physical Information: This entry will be primarily concerned with historical information; for anything else see NGC 1730.

Historical Identification: Per Dreyer, IC 2114 (Fleming #86, 1860 RA 04 55 19, NPD 159 25) is "planetary, stellar."
Physical Information: This entry will be primarily concerned with historical information; for anything else see NGC 1748.

Historical Identification: Per Dreyer, IC 2115 (Fleming #87, 1860 RA 04 56 44, NPD 156 36) is "planetary, stellar."
Physical Information: Although in the direction of the Large Magellanic Cloud, merely a foreground star in our own galaxy.

Historical Identification: Per Dreyer, IC 2116 (Fleming #88, 1860 RA 04 57 14, NPD 156 37) is "planetary, stellar."
Physical Information: Although in the direction of the Large Magellanic Cloud, merely a foreground star in our own galaxy.

Historical Identification: Per Dreyer, IC 2117 (Fleming #89, 1860 RA 04 57 39, NPD 158 39) is "planetary, stellar."
Physical Information: A 'knot' of nebulosity (and most likely, of stars lighting up that nebulosity) in NGC 1770. Apparent size 1.8 arcmin?

Historical Identification: Per Dreyer, IC 2118 (Wolf (MN lxv.), 1860 RA 05 00, NPD 97 25) is "faint, extremely large, irregular figure, III 500 involved to south," WH III 500 being NGC 1779.
Discovery Note: The reference to NGC 1779 is a considerable stretch, unless Wolf was referring to not only the nebula now listed as IC 2118, but also all other nebulosity in the region, as NGC 1779 is several degrees to the southeast of the IC object.
Physical Information: Dust in the region near the first magnitude star Rigel, which is to the left of the area shown here, scatters the star's blue-white light in the same way that our atmosphere scatters sunlight, lighting up what would otherwise be only a dark patch silhouetted against the starry background. Rigel and the nebula lie about 800 light-years from us. (Note: Although this is probably the same object listed as NGC 1909, that identification is less certain than for the IC entry; so despite the usual preference for using NGC designations, the nebula is usually referred to by its IC designation.)

Historical Identification: Per Dreyer, IC 2119 (Swift list XI (#74), Howe, 1860 RA 05 00 48, NPD 100 32.7) is "most extremely faint, pretty small, very difficult, 2 stars of magnitude 12.5 near."
Physical Information: Apparent size 1.1 by 0.7 arcmin?

Historical Identification: Per Dreyer, IC 2120 (Bigourdan #262, 1860 RA 05 09 36, NPD 51 58) is "extremely faint." Per Corwin, this is a duplicate observation of a comet Bigourdan observed an hour and a half earlier, but he did not organize and catalog his nebular observations until years after the fact, and apparently missed the duplication, leading to the IC entry. (There are several cases in which "lost" NGC/IC objects are suspected of being observations of cometary or other ephemeral phenomena, but due to Bigourdan's observations of this object being in such close proximity in both space and time, this is one of the most obvious.)
Physical Information:

Historical Identification: Per Dreyer, IC 2121 (Swift list XI (#75), Howe, 1860 RA 05 14 01, NPD 115 12.7) is "most extremely faint, small, round, very difficult, 7th magnitude star 14s preceding (west), 3.6 arcmin south". The position precesses to RA 05 19 45.0, Dec -25 03 57, right on the galaxy, and the starfield exactly confirms the identity. (See IC 408 for a discussion of the almost certainly incorrect suggestion that it might be the same as IC 2121.)
Physical Information: Apparent size 2.2 by 1.4 arcmin.

Historical Identification: Per Dreyer, IC 2122 (Swift list XI (#76), 1860 RA 05 14 12, NPD 127 15.6) is "pretty bright, extremely small, round, 3 stars north-following (to northeast)."
Physical Information: Apparent size 1.5 by 1.3 arcmin?

Historical Identification: Per Dreyer, IC 2123 (Barnard, 1860 RA 05 14 33, NPD 86 38.6) is "very small, round, much brighter middle, in a close pair with IC 2124, with a small (faint) star close to the north of the pair."
Physical Information: This entry will be primarily concerned with historical information; for anything else see IC 412.

Historical Identification: Per Dreyer, IC 2123 (Barnard, 1860 RA 05 14 35, NPD 86 38.7) is "very small, round, much brighter middle, in a close pair with IC 2123, with a small (faint) star close to the north of the pair."
Physical Information: This entry will be primarily concerned with historical information; for anything else see IC 413.

Historical Identification: Per Dreyer, IC 2125 (Swift list XI (#77), 1860 RA 05 18 49, NPD 117 06.9) is "most extremely faint, very small, round, very difficult."
Physical Information: Apparent size 1.0 by 0.7 arcmin?

Historical Identification: Per Dreyer, IC 2126 (Fleming #90, 1860 RA 05 22 20, NPD 158 05) is "planetary, stellar."
Physical Information: This entry will be primarily concerned with historical information; for anything else see NGC 1935.

Historical Identification: Per Dreyer, IC 2127 (Fleming #91, 1860 RA 05 22 38, NPD 158 06) is "planetary, stellar."
Physical Information: This entry will be primarily concerned with historical information; for anything else see NGC 1936.

Historical Identification: Per Dreyer, IC 2128 (Bailey, (Dunlop #176), 1860 RA 05 23 33, NPD 158 10) is "a cluster, with a few stars and nebulosity (in the Large Magellanic Cloud)."
Discovery Note: Many of Dunlop's observations could not be identified by John Herschel when at Cape Town, and as a result Dunlop's work was discredited in Europe, and all of the objects that he found and Herschel could not identify were ignored by Dreyer. However, recent research shows that Dunlop's #176 was this object, hence the credit given above, and my insertion of his name (in parentheses) in Dreyer's NGC entry. But since there was no mention of the object in the accepted literature, Bailey's discovery was just as valid as if no one else had ever seen it. (The note about the LMC was in the IC entry.)
Physical Information:

Historical Identification: Per Dreyer, IC 2129 (Swift list XI (#78), 1860 RA 05 25 25, NPD 113 10.2) is "most extremely faint, pretty small, round, 7th magnitude star south-south-following (to the south-southeast)."
Physical Information:

Historical Identification: Per Dreyer, IC 2130 (Swift list XI (#79), 1860 RA 05 25 50, NPD 113 16.6) is "extremely faint, pretty large, round, 7.5 magnitude star north-following (to the northeast)."
Physical Information: Apparent size 1.8 by 0.9 arcmin?

Historical Identification: Per Dreyer, IC 2131 (Swift list XI (#80), 1860 RA 05 26 04, NPD 107 19.6) is "pretty bright, very small, round."
Physical Information: This entry will be primarily concerned with historical information; for anything else see IC 422.

Historical Identification: Per Dreyer, IC 2132 (Howe (list I #6), 1860 RA 05 26 04, NPD 104 01.8) is "very faint, small." (Howe's paper states that this is near NGC 1954 and 1957, which is correct.)
Physical Information: Apparent size 1.5 by 0.8 arcmin?

Historical Identification: Per Dreyer, IC 2133 (Bigourdan #385, 1860 RA 05 26 47, NPD 20 42) is "very faint, pretty large, 13th magnitude star 0.7 arcmin south-following (to the southeast)."
Physical Information: This entry will be primarily concerned with historical information; for anything else see NGC 1961.

Historical Identification: Per Dreyer, IC 2134 (DeLisle Stewart #301, 1860 RA 05 27 46, NPD 165 34) is "considerably faint, very small."
Physical Information: Apparent size 1.0 arcmin?

Historical Identification: Per Dreyer, IC 2135 (Swift list XI (#81), 1860 RA 05 27 56, NPD 126 30.3) is "most extremely faint, extremely small, extremely extended, very difficult."
Physical Information: Apparent size 2.8 by 0.6 arcmin?

Historical Identification: Per Dreyer, IC 2136 (Swift list XI (#82), 1860 RA 05 27 59, NPD 116 32.5) is "extremely faint, pretty small, extremely extended."
Discovery Note: The duplicate entry appears to have been caused by a single-digit (10 degree!) error in the NPD, combined with more than 2 years between Swift's observations of the region.
Physical Information: This entry will be primarily concerned with historical information; for anything else see IC 2135.

Historical Identification: Per Dreyer, IC 2137 (Swift list XI (#84), 1860 RA 05 28 28, NPD 113 26.1) is "extremely faint, very small, round, 8th magnitude star 10s following (to the east), III 240 near," WH III 240 being NGC 1979 (which is to the north-northwest of this object). The position precesses to RA 05 34 18.0, Dec -23 20 16, but there is nothing there. However, there is an object which perfectly fits the description and in particular, the description of the star field, namely the galaxy discovered by Bigourdan a decade earlier, so there is no doubt that Swift made a single-digit (10 arcmin) error in the NPD, and his XI-84 is the same as Bigourdan's #384, or IC 2138, as shown in the titles for the pair of entries. Adding 10 arcmin to Swift's (1860) NPD changes the position to (2000) RA 05 34 17.3, Dec -23 30 16, less than 2 arcmin north-northwest of the galaxy listed above, and the 8th magnitude star to the east of the galaxy is just under 10 seconds of time to the east, so although Swift's position has an unfortunate (albeit common) error, his description is accurate, and the identification is essentially certain for Swift, and absolutely certain for Bigourdan.
Discovery Note: Swift observed this object twice, as his XI#83 on December 1, 1897, with the correct position but the wrong desccription and reference galaxy (NGC 1980), which is 17 degrees to the north of IC 2137/38, and as his XI#84 on Feb 14, 1898, with the wrong position but with a correct description and reference galaxy (NGC 1979). On the first occasion he had a good position, but had the nearby star to the west, which is wrong, and placed it southeast of NGC 1980, which is 17 degrees to the north of the recorded position, and is therefore an obvious mistake; so Dreyer must have ignored that error, presumed that Swift XI#83 was a duplicate observation of Bigourdan #384, and therefore ignored XI#83 in his IC2 entries, except for using Swift's description for IC 2138, not Bigourdan's. On the second date, Swift placed the star to the east, and listed the correct nearby galaxy (NGC 1979), but made the aforementioned error in the declination of his 'nova'. Due to the different position and description Dreyer obviously thought that XI-84 was a completely different and previously undiscovered object, and listed it as IC 2137.
Designation Error: Since Swift's first observation of this object was his #83, Steinicke lists this object as XI-83; but as noted above, Dreyer must have used XI-84 for IC 2137, as its position and description are the ones shown in the IC2. However, the discovery date for XI-83 is the appropriate one, since XI-83 and XI-84 are actually the same object.
Designation Note: As noted in the titles for their entries, IC 2137 is the same object as IC 2138, and it is common practice to use the smallest numerical designation for NGC/IC objects, so IC 2137/38 is always referred to as IC 2137, which is why this entry contains everything else about the object, and the entry for IC 2138 only has historical information.
Image Misidentifications: For some reason, a search of Wikisky or AladinLite for IC 2137 shows NGC 1979, instead of IC 2137/38. Both LEDA and NED correctly show that IC 2137 and 2138 are the same object, well to the southeast of NGC 1979, so there is a blunder in some database, but which one is not obvious (perhaps the RNGC?).
Physical Information: Apparent size 1.2 by 0.8 arcmin?

Historical Identification: Per Dreyer, IC 2138 (Bigourdan #384 (= Swift list XI #83), 1860 RA 05 28 33, NPD 113 38) is "extremely faint, small, 2 stars involved 1/2 arcmin apart, 7th magnitude star preceding (to the west)." The position precesses to RA 05 34 22.2, Dec -23 32 11, less than 0.3 arcmin southeast of the center of the galaxy listed above and on its southeastern rim, and although the description of the field is backwards (the 8th magnitude star is to the east, not west) the error is not Bigourdan's but Swift's, and there is nothing else nearby, so the identification is certain.
Discovery Note: Bigourdan's papers do not mention the relatively bright star at all; but Swift's list XI#83, which is a duplicate but "opposite" observation of Swift's list XI#84 (the former has a good position but the wrong description, while the latter has a correct description but the wrong position), precesses to (1860) RA 05 28 20.3, NPD 113 38.3, and although a bit (2.8 arcmin) nearly due west of the galaxy listed above, it must have been close enough to Bigourdan's #384 to make Dreyer think it represented the same object, as he obviously adopted Swift's XI#83 as a duplicate observation of Bigourdan's discovery, since he used Swift's (wrong) description of the object (though not giving Swift any credit in the IC2 entry, presumably because his observation was a decade later). However, since Swift's description was used, I have parenthetically added his observation to the IC2 entry shown above.
Designation Note: As noted in the titles for their entries, IC 2137 is the same object as IC 2138, and it is common practice to use the smallest numerical designation for NGC/IC objects, so IC 2137/38 is always referred to as IC 2137, which is why this entry only contains historical information.
Physical Information: Given the duplicate entry, see IC 2137 for anything else.

Historical Identification: Per Dreyer, IC 2139 (Bigourdan #263, 1860 RA 05 29 06, NPD 108 02) is "a cluster, very very small (12 arcsec), looks nebulous."
Physical Information:

Historical Identification: Per Dreyer, IC 2140 (DeLisle Stewart #302, 1860 RA 05 37 58, NPD 165 27) is "extremely faint, very small, an extremely small cluster?"
Physical Information: Apparent size 2.1 arcmin?

Historical Identification: Per Dreyer, IC 2141 (Innes (#4), 1860 RA 05 39 00, NPD 141 06) is "faint, very small, round, brighter middle."
Physical Information:

Historical Identification: Per Dreyer, IC 2142 (DeLisle Stewart #303, 1860 RA 05 40 34, NPD 168 05) is "extremely faint, very small, a little extended 25°, a little brighter middle."
Physical Information: Apparent size 0.8 by 0.4 arcmin?

Historical Identification: Per Dreyer, IC 2143 (Swift list XI (#85), Howe, 1860 RA 05 40 45, NPD 108 46.8) is "extremely faint, pretty small, very much extended 45°, 3 stars south-following (to the southeast)."
Physical Information: Apparent size 2.0 by 0.8 arcmin?

Historical Identification: Per Dreyer, IC 2144 (Barnard, 1860 RA 05 41 41, NPD 66 10.5) is "pretty faint, extremely small, 12th magnitude star 2 arcmin north-north-preceding (to the north-northwest), 12th magnitude star 1 arcmin south."
Physical Information: Apparent size 1.0 arcmin?

Historical Identification: Per Dreyer, IC 2145 (Fleming #92, 1860 RA 05 41 46, NPD 159 44) is "planetary, stellar."
Physical Information: Apparent size 2.0 arcmin?

Historical Identification: Per Dreyer, IC 2146 (DeLisle Stewart #304, 1860 RA 05 42 02, NPD 164 51) is "a cluster, very faint, btween 2 stars."
Physical Information: Apparent size 2.6 arcmin?

Historical Identification: Per Dreyer, IC 2147 (Swift lixt XI (#86), 1860 RA 05 42 28, NPD 120 32.9) is "most extremely faint, pretty small, round, faint star north-preceding (to northwest)."
Physical Information:

Historical Identification: Per Dreyer, IC 2148 (DeLisle Stewart #305, 1860 RA 05 44 07, NPD 165 38) is "very faint, very small, brighter middle."
Physical Information: Apparent size 1.1 arcmin?

Historical Identification: Per Dreyer, IC 2149 (Fleming #105, 1860 RA 05 45 56, NPD 43 55) is "planetary, stellar."
Physical Information: Apparent size 1.05 by 1.0 arcmin (for outer more or less circular structure).