The next boundary segment is a precious relic indeed. It runs north-south from the north bank of the Little Colorado down along 13 sections to the point where the boundary turns west. It is the only segment that remains as evidence of the original 1882 Powell-Harrison proposal presented in S. 1849. Their line used the longitude 111°45'. GLO preferred to use 2-½ miles due east of the junction of the Colorado and Little Colorado to locate the north-south line. However, when Harrison proclaimed the Grand Canon Forest Reserve in 1893, it was back to 111°45'. All this was before the land was surveyed and overlain with our grid of townships. Here are maps that show the original line: the first uses the mileage measure on an 1879 GLO base. The second uses longitude on an up-close view of the Forest Reserve.
Looking closely at the junction, you can see a township line right there, and counting over two sections, see how the boundary is now ½ mile west of the original (to help, I lightly extended the 111°45' line north). I suppose this makes the line a double artifact, first of the original proposal, and second of how the switch to surveyed legal lines itself could shift a boundary. Do not be fooled, by the way, by BLM having awarded Navajo land below the Marble rim to the Park, as if the Navajo had concurred. The Park line is along the the east and north river banks. Still, it is the prettiest map.
Now lets consider the historical question: Did these boundary shifts result only from the different ways of locating the boundary, or was there substantive reason to give that half-mile to the Navajo? In this case, I suspect no one cared about that ½-mile strip; the rim of the Canyon was protected; there were no trees worthy of a Forest Reserve; sheep seemed to be the big concern. In the period before 1910, Navajo and whitefolk did compete over sheep grazing, with proposals for adding to and deleting from what was for a short time a part of Coconino NF. Still, I opine that what started out in 1893 as a boundary along a longitude, ended up in the 1910 Tusayan NF proclamation map for convenience as a boundary along then-unsurveyed township lines. The Navajo Reservation was extended to the Tusayan boundary by name, wherever the latter had got to. So the Navajo didnt get away with anything, even if the then-NF lost 4000 acres or so. Perhaps buried somewhere in the files there is a rectification of the discrepancy, a note from a clerk in GLO recognizing and fixing a hole progress had made.
Now, more truth. When TR proclaimed the Monument, only a couple of miles south of the Little Colorado north bank were included, before the line cut west a mile. The rest was left in the National Forest. Here is the Tusayan 1910 map, the least elegant, least information-full of this bunch.
The Monument line is the dark one surrounding the arc of the Colorado. I added some pencilled squiggles to show the Little Colorado's course. The "X" marks where the GCNM boundary is coming down section lines and hits the LCR midstream. (Ignore the diagonally marked blocs; they were in the Forest, but not GCNM.)
The 1919 Park Act followed section lines here. They were superseded by the 1927 changes, which switched to the topographic description of the banks of the Colorado and Little Colorado, and then used this legal-line language:
thence southeasterly along said bank, to the north bank of Little Colorado River; thence easterly along said bank of Little Colorado River to its intersection with what probably will be when surveyed the east line of section 32, township 33 north, range 6 east, or the east line of section 5, township 32 north, range 6 east; thence southerly along projected section lines.
Sounds a bit uncertain; a map is so much more definite. Comparison with the BLM map above shows what happened as a result of the switch to legal lines. On the 1910 map, before the survey was done, T33N has the standard 6 sections north to south. The BLM map shows however, that when the survey was complete, two extra lines of sections (T32-½N and T33-½N) had to be inserted, making about seven, instead of the standard 6 miles. The reason there were only seven instead of eight is that the topmost six sections of 33 were used to make up the six sections of 33-½. (!?)
The 1927 bill drafters had probably thought they were covered, but when the sections were surveyed and T33-1/2N inserted, the Little Colorado fell right into it, with the boundary just nicking into the line of the T32-½N sections. So the boundary does not go to either of the choices in the 1927 Act; instead it runs
easterly along said bank of Little Colorado River to its intersection with the east line of section 32, township 32-½ north, range 6 east; thence southerly along section lines.
Nobody seems to mind. (And as I discussed under segment B, that land left behind, north of the LCR, shortly went to the Navajo Reservation.)
Lengthwise, when the Park bill passed in 1919, 6 more miles of "original" boundary to the south were added to the two left by the Monument proclamation. When the next round took place, in the Act of 1927, the "restoration" was extended, also from Forest land, five more miles to its present location, so it runs from the LCR north bank to the northeast corner of sec. 8 in 30N,6E. Since the language used was "its intersection with what probably will be when surveyed section 8", it might have been more fun to honor Powell-Harrison by shifting it back to the longitude.
On the other side of the line, the Navajo boundary had been extended in Jan 1918 to what was then the Tusayan National Forest boundary up to the Little Colorado. So until 1927, a few sections of Tusayan remained between Monument/Park and Reservation. After that, the entire 13 miles of boundary from the LCR north bank to its west turn at the se corner of sec. 5, T30N, R6E, is common to the GCNP and the Navajo.