The same western limit, beginning at the same initial point, proceeds thence in a course nearly southwest, through Behring’s Straits and Behring’s Sea, so as to pass midway between the northwest point of the island of St. Lawrence and the southeast point of Cape Choukotski, to the meridian of one hundred and seventy-two west longitude; thence, from the intersection of that meridian, in a southwesterly direction, so as to pass midway between the island of Attou and the Copper Island of the Kormandorski couplet or group, in the North Pacific Ocean, to the meridian of one hundred and ninety-three degrees west longitude, so as to include in the territory conveyed the whole of the Aleutian Islands east of that meridian. The whole of the Aleutian Islands from Attou east is included in the US territory.
As the the treaty stated, Copper Island is part of the Kormandorski couplet, not the Aleutian Islands. Just as the map you posted in #57 showed, the Western end of the Aleutians ends at Attou.
Are you trying to claim that Copper Island, separated by over 200 miles from Attou is part of the Aleutian Islands but Behring, about 30 miles from Copper is not? The 193 meridian divides these two.