The boundary of the Grand Canyon National Park is changed so as to read as follows:

Beginning at a point on the present south boundary of Grand Canyon National Park, being the northeast corner of township 30 north, range 1 east, of the Gila and Salt River meridian, Arizona; thence westerly along north line of said township to the northwest corner of section 1, said township; thence northerly along west line of section 36, township 31 north, range 1 east, to a point one-half mile south of the center line of the Supai road survey as mapped and staked by the Bureau of Public Roads during the field season of 1925; thence in a northwesterly direction following a line, which maintains a uniform distance one-half mile south and west of the center line of said road survey, to its intersection with the projected section line between what probably will be when surveyed sections 9 and 16, township 32 north, range 2 west; thence westerly along projected section lines through probable townships 32 north, ranges 2, 3, and 4 west, to its intersection with the upper west rim of Havasu (Cataract) Canyon; thence northwesterly along said upper west rim, crossing Hualapai Canyon to Wescogame Point and continuing northwesterly along said upper rim to Watahomigie Point; thence due north along the top of a ridge a distance of approximately three-fourths of a mile to the point of said ridge, the elevation of which is given as four thousand eight hundred and sixty-five feet; thence northwesterly, crossing Beaver Canyon, to Yumtheska Point and continuing northwesterly, following the lower rim of Yumtheska Point, crossing the projected range line between ranges 4 and 5 west to the divide west of Havasu Creek; thence northerly along said divide to the north bank of the Colorado River; thence northeasterly along said bank to the divide immediately west of Tapeats Creek; thence northeasterly along said divide, including the entire drainage area on the north side of Tapeats Creek, to the point at which this divide touches the ledge of cross-bedded sandstone; generally known as the Coconino sandstone; thence southerly along said sandstone ledge to its junction with the Gila and Salt River meridian; thence southerly along the Gila and Salt River meridian to the northwest corner of what will probably be when surveyed section 18, township 34 north, range 1 east; thence easterly along projected section lines to the northeast corner of what will probably be when surveyed section 14, township 34 north, range 2 east; thence southerly along projected section line to the southeast corner of said section 14; thence easterly along projected section lines, a distance of approximately six miles to a point on the divide between South Canyon and Thompson Canyon; thence southeasterly along said divide, including the entire drainage area of Thompson Canyon and Neal Spring Canyon, to the intersection with the upper rim of the Grand Canyon; thence easterly along the main hydrographic divide north of Nankoweap Creek and Little Nankoweap Canyon to its intersection with the Colorado River, approximately at the mouth of Little Nankoweap Canyon; thence due east across the Colorado River to the east bank of the Colorado River; 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 to the northeast corner of what probably will be when surveyed section 8, township 30 north, range 6 east; thence westerly along projected section lines to the southwest corner of what probably will be when surveyed section 6, township 30 north, range 5 east; thence southerly to the northeast corner of section 13, township 30 north, range 4 east; thence westerly to the northwest corner of said section 13; thence southerly to the southwest corner of said section 13; thence westerly along section lines to a point nine hundred and fifty feet west of the northeast corner of section 22, said township; thence due south a distance of one thousand three hundred and twenty feet to a point on the south line of the north tier of forties of said section 22; thence westerly to the west line of said section 22; thence southerly along said west line, to the southwest corner of said section 22; thence westerly along section lines to the southwest corner of section 19, township 30 north, range 4 east; thence northerly to the northwest corner of said section 19; thence westerly to the southwest corner of section 14, township 30 north, range 3 east; thence northerly to the northwest corner of said section 14; thence westerly on section lines to the southwest corner of section 12, township 30 north, range 2 east; thence northerly along section lines to the north line of said township 30 north, range 2 east, thence westerly along said north township line to the place of beginning; and all of those lands lying within the boundary line above described are included in and made a part of the Grand Canyon National Park; and all of those lands excluded from the present Grand Canyon National Park are included in and made a part of the contiguous national forests, subject to all national forest laws and regulations.