It will be seen from his report that such an obstruction does exist, but it is of less importance than I was led to believe, because it is only about one-third of a mile from the shore, where the chart calls for 12 feet of water, instead of 1 mile from the shore, where the chart shows a much greater depth.

It can hardly be regarded as an obstruction to large vessels, though it might be dangerous to small ones.

The original lake survey sheet is mailed to you to-day in a separate package.

I have the honor to be, very respectfully, your obedient servant,
DAN C. KINGMAN,
Captain of Engineers.

Brig. Gen. THOMAS L. CASEY,
Chief of Engineers, U. S. A.

REPORT OF MR. WILLIAM PIERSON JUDSON, ASSISTANT ENGINEER.

UNITED STATES ENGINEER OFFICE,
Oswego, N. Y., October 27, 1891.

SIR: I have the honor to report that, in compliance with your orders to find, and make a survey of unlocated rocks said to lie in Lake Ontario about 4 miles west of Little Sodus, I left Oswego on the night of October 2 with the steamer Hasleton (which had been hired at $10 per working day or $5 per idle day), ran in to Little Sodus for the night, and, on the morning of the 3d found the shoal in question, with the aid of George Carter, a fisherman, whose partner had reported its existence. The main rock in the shoal has 4 feet depth at present stage of water level (1 foot above extreme low water), and lies one-third mile off the Black Creek outlet, where the lake survey chart shows 12 feet depth.

Conspicuous landmarks were identified on the original detail sheet of the lake survey, and a base line was located on the beach by triangulation from these landmarks. From this base line buoys on the shoal were located, checked by sextant angles taken at the buoys. Five deeper rocks near the main and largest one were also located, and the vicinity for one-half mile radius was closely examined to obtain assurance that no shoal spots were overlooked. The only rocks to be noted were five, which were found within 200 feet of the shoalest and largest one.

The details are fully given upon the maps* herewith submitted.

ANNUAL WATER-LEVEL CURVES OF THE NORTHERN AND NORTHWESTERN

LAKES.

Tridaily observations were made at Charlotte, N. Y., on Lake Ontario, from July, 1887, to June 30, 1892, and at Oswego, N. Y., from July, 1890, to June 30, 1892. Observations were also made at Cleveland Harbor, Ohio, and at Erie Harbor, Pa., on Lake Erie, from July, 1887, to June 30, 1892; at Milwaukee, Wis., on Lake Michigan, from July, 1887. to June 30, 1892, and daily observations at Escanaba, Mich., on Green Bay, from July, 1887, to June 30, 1892. At the last-named place observations were not made in January, February, March, and

*Omitted.

April of 1888, nor in January, February, and March of the years 1889, 1890, 1891, and 1892, by reason of ice and snow.

Daily observations were made at Sand Beach, Mich., on Lake Huron, and at Sault Ste. Marie and Marquette, Mich., on Lake Superior, from July, 1887, to June 30, 1892.

The accompanying tables and plates are continuations of those published in the Annual Report of the Chief of Engineers for 1887, Part III, page 2418.

Monthly mean of water levels for the several stations below the planes of reference adopted in 1876. (See plates).

Stations.

1887.

1888.

June. July. Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. May. June.

Sault Ste. Marie... 3.317 2.947 3.064 3.005 3.031 3.260 3.665 3.815 4.166 4. 115 4. 125 3.524 2.675

2.95 3.11 3.34 3.68 3.81 3.85 3.73 3.43 3.36 3.19 2.94 2.50
1.90 1.97 2.38 2.60 2.60 2.60 2.67 2.81 3.12 2.79 2.66 2.13
1.85 1.95 2.39 2.76 2.70 2.82 2.80 2.96 3.12 2.77 2.59 2.16
2.48 2.60 2.75 3.00 3.05 3.63 3.65 3.68 3.70 3.69 3.61 3.15
2.66 2.77 2.93 3.18 3.45 3.80
4.04 3.98 3.55
2.52 2.48 2.78 3.07 3.25 3.46 3.60 3.68 3,70 3.77 3.63 3.30
2.38 2.25 2.30 2.39 2.52 2.88 3.34 3.40 3.58 3.40 3.22 3.09
2.518 2.523 2.604 2.620 2.819 3. 158 3.432 3.722 3.700 3.705 3.144 2.965

Charlotte..

Oswego

Erie.

Cleveland

Milwaukee.

1.23 1.80
1.06 1.78
1.55 2.01

1.50 1.94

3.11

3. 19

Escanaba.

3.44

Sand Beach

3. 14

Marquette

Sault Ste. Marie...

2.27 2.50 2.55 2.78 3.10 3.02 2.43 1.86 1.93 2.34 2. 14 2.46 2.38 2.62 2.91 2.66 2.12 1.61 1.86 2.27 2.31 2.37 2.23 2.40 2.78 2.72 2.48 2.51 2.70 2.56 2.13 2.32 2.35 2.58 2.80 2.82 2.36 2.49 2.67 2.53 3.39 3.50 3.84 4. 19 4.21 4.45 4.26 3.95 3.85 3.70 3.55 3.65 3.89 4.36 4.53 4.38 4.22 4.19 3.14 3.41 3.62 3.82 4.12 4.32 4.43 4.46 4.13 3.89 3.94 2.94 2.79 2.66 2.69 2.90 3.26 3.63 3.76 3.80 3. 84 3.64 3.58 2.695 2.786, 2.897 2.641 3. 104, 3. 408 4.098 3.987 4.133 3.959 3.529 3.580

1.84

1.85

2.65 3.02 3.44 4.07 4.77 4.76 4.55 4.62 4. 64 4.22 3.98 3.40
12.55 2.99 3.42 4.06 4.66 4.69 4.59 4.62 4.49
3.92 3.85 3.29
2.56 2.85 13.06 3.39 3.60 3.48 3.43 3.97 3.80 3.36 2.56
12.63 2.90 13.08 3.46 13.90 3.83 3.80 4.01 3.97 3.41 2.61
3.871 3.936 4.170 4.531 4.926 4.986 4.874 4.676 4.777 4.716 4.297 3.854
4. 269 4.430 4.515 4.796 5.220 5.280
5. 200 4.917 4.450
4.01 4.20 4.57 4.88 4.94 4.92 4.98 4.92 4.84 4.71 4.18
3. 228 3.231 3.074 3.37 3.90 3.90 4. 18 4.31 4.30 3.97 3.59
3. 468 3.456 3.522 3.466 3.575 3.840 3.945 4.303 4.483 4.331 3.820 3.460

3.91
3.39

The following corrections are to be made in the monthly mean of water levels for Lake Erie below the plane of reference adopted in 1876, as given in the Annual Report of the Chief of Engineers for 1887, Part III, page 2418:

APPENDIX D D D.

CONSTRUCTION AND IMPROVEMENT OF ROADS AND BRIDGES IN THE YELLOWSTONE NATIONAL PARK.

REPORT OF MAJOR WILLIAM A. JONES, CORPS OF ENGINEERS, OFFICER IN CHARGE, FOR THE FISCAL YEAR ENDING JUNE 30, 1892.

UNITED STATES ENGINEER OFFICE,

St. Paul, Minn., July 1, 1892.

GENERAL: I have the honor to submit herewith my report of operations for the improvement of Yellowstone National Park during the fiscal year ending June 30, 1892.

Very respectfully, your obedient servant,

Brig. Gen. THOMAS L. CASEY,

Chief of Engineers, U. S. A.

W. A. JONES,

Major, Corps of Engineers.

The project for this work was adopted in 1883, when the control was placed in the hands of officers of the Corps of Engineers, and consists in the construction and maintenance of about 225 miles of road, with the necessary bridges, culverts, etc. The roads embraced in the project commence at Gardiner, at the north boundary line of the park, thence to Mammoth Hot Springs; thence to Upper Geyser Basin, passing through Norris Geyser and Lower Geyser basins; thence to the outlet of Yellowstone Lake via Shoshone Lake and the west arm of Yellowstone Lake, crossing the Continental Divide of the Rocky Mountains twice; thence to Yanceys, via the Falls and Grand Canyon of the Yellowstone River; thence to Mammoth Hot Springs, completing the so-called belt road, with a circuit of about 145 miles. In addition there are projected: A road from the west boundary line of the park, passing through Lower Geyser Basin, and continued easterly to intersect the road along the Yellowstone River to the falls; a road from Norris Geyser Basin to the Falls of the Yellowstone; a road from Yanceys to the east bounday line of the park, and a number of short branch roads and trails from the above-named roads to objects of interest off the main line of travel; in all, 225 miles of new road,