The stormy weather that continued most of the month of September delayed us considerably, especially in landing on the rocky shores. The plan of work that we followed was to land a party of 7 or 8 with camp outfit at a point where one of the larger stations was to be built, and, with the rest of the party and tug, put up the smaller stations till the larger station was completed, then return and move the party and camp to the next point.

The work was carried on in this manner till 14 stations had been finished and another one begun, when the work was interrupted by the burning of the Mystic on September 27, with all the property, both Government and private, that was on board at the time. Eight of the party were in camp on Maple Island at the time of the fire with a large part of the outfit. The rest of the party were on shore with me, about 2 miles from the tug.

The loss of the tug caused us to return to Sault Ste. Marie, and the Government tug Myra was sent to Maple Island to bring back the rest of the party as soon as they had finished that station.

During the time that we had the Mystic, Capt. Moiles assisted us in every way in his power, sending as many of the tug's crew as he could spare to assist us in landing, and also at times to assist in clearing lines.

On October 3 Mr. R. L. Ames, my recorder, left to resume his college work at Ann Arbor, having given the best of satisfaction in all his work.

On October 2 I started with the party to build a station on the site of the old Lake Survey station Mamainse. We took passage on the steamer Telegram, which landed us on the north shore of Batchewana Bay, about 9 miles from the station and near the old mining dock. As no horses could be obtained in that locality, we pitched our camp on the shore and had all our provisions carried out to us while we were building the station and cutting a trail back to the shore. Two Indians, Tommy Robinson and Jim Narsaub, were engaged as guides and to carry provisions for us.

We were delayed a few days after the work was finished through not being able to get transportation to Sault Ste. Marie as soon as we wished.

It was decided upon our return that no more stations would be built during the season as the appropriation was running low, so our outfit was cleaned, repaired, and stored away in the Government warehouse, and party disbanded.

In company with Mr. Thomas Russell I made a week's trip among some hills about 30 miles south of Sault Ste. Marie to determine their height by barometrical readings for Mr. Morley's use in planning triangulation.

I closed the field for the season with the building of an 18-foot station at South Gros Cap in place of the 4-foot one already there, so as to be able to read the line South Gros Cap-Larke in both directions.

From the close of the field work to the close of the fiscal year 1894 I have been engaged in general office work, varied by occasional short trips to points connected with the triangulation, except for the months of March and April, during which I was on duty connected with the improvement of the 20 and 21 foot channel, such as sounding through the ice, plotting notes, computing, etc.

The cost of building stations, clearing lines, etc., during the year has been as follows:

The Government tug Myra has been utilized a number of times in transporting the party and supplies to stations along the river, thereby saving us from considerable expense and delay.

The following table shows the approximate cost of the stations, cost per vertical foot of height, and also of clearing lines and roads. In the column for height the entire vertical height of the tripod is given. In determining the cost of the stations, the cost of the outfit, hardware, etc., was divided among the stations in proportion to their height.

Duke. Is in the northeast quarter of the northwest quarter of Sec. 33, T. 44 N., R. 1 W., Chippewa County, Mich. Height of station 108 feet (sill to top of tripod). The geodetic point consists of a §-inch hole between the letters U. S. cut in top of a stone 6 by 6 by 24 inches, set about 4 feet below surface, with a 6-inch post with a nail center set over it for a surface mark. Two reference stones were set on a line 33 feet north of the section line between sections 33 and 28. These were common field stones with crosses cut in top and letters U. S. on side facing station. Size of stones about 10 by 14 by 30 inches. The cross on the west stone bears N. 46° 30′ W. 203.7 feet from the geodetic point. The cross on the east stone bears N. 55° E. 236.75 feet from the geodetic point. Distance between reference stone, 344 feet. Center of 36-inch pine stump S. 48° W. 59.5 feet. Fifteen-inch pine near the road N. 21° E. 173

feet.

Rankin Mountain.-Is on a projecting point of a range of mountains about 7 miles northeast of Sault Ste. Marie, Ontario, and is north of the wagon road to Garden River, and east of an old mining road up to the mountain. The geodetic point is a 4-inch nail cemented into the rock, with a triangle cut into the rock around it, also the letters U. S. Reference points are two crosses cut into the rock; (1) bearing N. 53° 15′ W. 57:75 feet, (2) bearing S. 25° 30′ W. 60.9 feet. These two crosses are 90.95 feet apart. A 16-inch pine tree bears N. 83° W. 445 feet from the geodetic point. Kings Mountain.-Is on the highest point of what is called Kings or Slate Mountain, in the northern part of section 5, Vankoughnet township, Ontario. Only a tripod was placed there, as it was not certain that it would be needed. The hill is the most prominent one in sight northeast of Goulais Bay and north of Goulais River. Phillips.-Is situated on the highest peak of a mountain about 9 miles east of Echo Bay station and about 10 miles north of Stobie station, both on the Canadian Pacific Railroad, and about 1 mile north of a small lake on land owned by Mr. Hugh Phillips. The station is supposed to be in lot 4 of the third concession of Coffin Addition, Ontario. Top of tripod is 36 feet above ground. Geodetic point is a §-inch hole between the letters U. S. in the top of a cut stone 6 by 6 by 24 inches and 33 feet below surface. A wooden post with nail in center set above stone for surface mark. Reference stones are four field bowlders with crosses and letters U. S. on them. They are set in a square with sides 35.35 feet. The geodetic point is in the exact center of the square and 25 feet from the cross on each stone. Crosses are approximately north, south, east, and west of the geodetic point. A 24-inch maple bears S. 85° 44' E., and is 64 feet distant.

Salters Hill.-Is on the northwest edge of a hill on St. Joseph Island, known as Salters Hill, about half a mile south of the Hilton road and 34 miles from the west shore of the island. Top of tripod about 70 feet above the ground. The geodetic point is a g-inch hole between letters U. S. in top of cut stone 6 by 6 by 24 inches, set about 3 feet below surface, with a wooden post with nail center set above it for a surface mark. Reference stones consist of four field stones left in their natural

beds, but with cross and letters U. S. cut on each. Bearings and distances to them are as follows: (1) N. 3° E. 60.72 feet; (2). S. 75° 30′ E. 32.4 feet; (3) S. 7° E. 60.9 feet; (4) S. 84° W. 44.7 feet. Distance between crosses on reference stones (1 to 2) 74.2 feet; (2 to 3) 57.6 feet; (3 to 4) 76.3 feet; (4 to 1) 80.5 feet.

Whitefish. This station is located on a small sand hill about 560 feet southwest of the center post of the Whitefish Point light tower. The tripod of the station is 40 feet high and set 5 feet in the sand. The geodetic point is a g-inch hole between the letters U. S. and the top of a stone 6 by 6 by 24 inches, set 6 feet below surface with an oil barrel around it. Post with nail in center set over it for a surface mark. Reference stones are two cut stones 2 feet long with tops dressed to 4 inches and letters U. S. cut on the side facing station. These are set in the ground at the foot of the sand hill and with the bearings and distances as follows: (1) N. 12° E. 120 feet; (2) S. 75° W. 120 feet. Center post of steel light tower N. 56° E. 560.8 feet. Astronomical post S. 34° E. 825.5 feet. Center of astronomical post to center post of steel light tower 1,007.36 feet.

Parisian.-Is on the highest point of the ridge that runs along the west side of Parisian Island. Top of tripod is 36 feet above ground. The geodetic point is a -inch hole between the letters U. S. and the top of a cut stone 6 by 6 by 24 inches and set 2 feet below the surface. Two reference stones (common field stones), with cross and letters U. S. cut on them, are set as follows: (1) Stone bears N. 18° 30′ E. 24 feet; (2) N. 720 W. 50 feet from the geodetic point.

North Gros Cap.-Is on the rock point that projects into Whitefish Bay and forms the southern limit of Goulais Bay. A4-foot station was put up here, setting on the solid rock. Geodetic point is a -inch hole drilled in the rock with a triangle (6-inch sides) cut around it. Reference marks are two crosses cut in the rock with letters U. S. near them. (1) Cut in sloping face of rock, bears nearly east and is 43.22 feet from geodetic point; (2) bears S. 60° E. 70.75 feet from geodetic point, and is cut in the vertical face of rock near a 6-inch oak tree.

Maple Island.-Is on the west shore of the island of the same name, about 40 feet from the water's edge. The station is about 35 feet high. The geodetic point is a well-shaped field stone about 6 by 5 by 24 inches, with a hole drilled in the top between the letters U. S. The stone is set with the top 6 inches below surface. But one reference mark was made; a cross and letters U. S. were cut on a large bowlder N. 6° W. and 104.2 feet from the geodetic point. Corbay Point light bears N. 9° 33' W. from the station.

Maple Point.-Is on a projecting point on the south shore of Goulais Bay. The station consists of a 6-foot tripod set 2 feet in the ground. The geodetic point is the original Lake Survey mark, a lead center between the letters U. S. on the top of a cut stone 6 by 6 inches by (length unknown), set with top about 1 foot below surface and about 45 feet back from shore. Reference marks are a cross cut on a large bowlder in the water about 15 feet from shore, bearing N. 47° W. 61.9 feet from the geodetic point, and an 8-inch birch tree bearing S. 37° 30′ W. 36.55 feet.

Goulais River.-Is on the sandy shore a few hundred feet north of the middle mouth of the Goulais River and about 60 feet from shore. Station is a wooden post 12 inches by 8 feet, set with top about 42 inches above ground. This is the same point occupied by the old Lake Survey post. A long-necked bottle is set below this post, and is directly under the spot occupied by the center of the old post.

North Bay. Is about 2 miles north of the Goulais River station and about 30 feet from shore. The station consists of a 10-inch spruce tree cut off about 4 feet above ground and covered with a plank cap. A platform was built around the stump for observer to stand on. The geodetic point is 4-inch iron rod 6 inches long driven into the stump. Reference points are crosses on two bowlders near water's edge. (1) South 36.7 feet; (2) southwest 34.8 feet.

Mission.-Is about 1 mile north of the Indian settlement on Goulais Bay and about 20 feet from the shore. The station is a poplar stump treated as at North Bay. Reference points are crosses on two bowlders (rather small). (1) North 14.36 feet; (2) southwest 39.2 feet.

Buchanan.-Is on the edge of a bluff at the shore on Buchanan Point, about onehalf mile west of the Indian settlement in Goulais Bay. The station is a 6-foot tripod set 2 feet in the ground. The geodetic point is a §-inch hole between the letters U. S. in top of a cut stone 6 by 6 by 24 inches set 18 inches under surface. Reference points are a 10-inch pine tree northeast 58.19 feet, and an 8-inch oak tree northwest 40.4 feet.

Goulais Point.-Is near the end of the point of land that separates Goulais Bay from Whitefish Bay, about 30 feet from shore. The station is a 4-foot tripod set 8 inches in the ground. The geodetic point is a g-inch le between the letters U. S. cut in the top of a stone 6 by 6 by 24 inches, and set 6 inches below the surface with a flat stone above it.

Sand Point.-Is on the long sandy point that projects out from north shore of Batchewana Bay toward the east end of Batchewana Island. The station is a 6-foot tripod

set about 24 feet in the sand. The geodetic point is a cross cut on the top of a dressed stone 4 by 4 by 24 inches, and set with top 6 inches above surface.

Crawford. Is on the edge of a bluff near the shore, about one-fourth of a mile west of Crawford's landing, and about 14 miles northeast of Corbay Point light. The station is a 4-foot tripod. The geodetic point is a cross on a dressed stone 4 by 4 by 24 inches, set 6 inches above surface. Letters U. S. cut on side of stone.

South Parisian.-Is an 8-foot wooden post set 44 feet in the ground as near as it was possible to locate, where the old Lake Survey station was, on the south end of Parisian Island. The remains of the old station were found, but I could find nothing of the old geodetic point.

Salt Point. Is on the extremity of a point of land on the south shore of Whitefish Bay, about 9 miles west of Iroquois Island and about 30 feet from shore; 20-foot tripod put up here; rest of station unfinished. The geodetic point is a -inch hole between the letters U. S. in the top of a cut stone 6 by 6 by 24 inches, set with top 3 inches above surface of the ground.

Mamainse. Is the same point that the old lake survey used, and is on the highest peak in the vicinity, about 8 miles north of Batchewana Bay, and 8 miles east of Mamainse Point. The station is set on solid rock and is 28 feet high. The geodetic point is -inch hole between the letters U. S., cut in the flat top of a field stone, about 2 feet long, and set down to the solid rock, with top 6 inches below surface. Reference points are: (1) Center of top of old astronomical post southeast 68.44 feet; (2) cross and U. S. on rock just to left of line to astronomical post, 22.68 feet distant; (3) cross and U. S. on rock nearly south 43.84 feet.

South Gros Cap.—Mentioned in my report for the fiscal year ending June 30, 1893, as "Gros Cap." The station has been changed from a 4-foot one to an 18-foot one. For descriptions of the rest of the stations built during 1893, see my annual report for that year.

A set of silver prints,* from negatives taken during the progress of the work, is submitted with this report.

Very respectfully, your obedient servant,

First Lieut. CHARLES S. RICHÉ,

Corps of Engineers, U. S. Army.

GLEN E. BALCH,
Assistant Engineer.

E. REPORT OF MR. E. E. HASKELL, ASSISTANT ENGINEER.

UNITED STATES ENGINEER OFFICE,

Sault Ste. Marie, Mich., June 16, 1894. SIR: I have the honor to make the following report upon the field work of the angle reading and the reduction of the observations of the primary triangulation of the resurvey of St. Marys River, Michigan.

NARRATIVE.

The field work of the angle reading began July 5 and lasted until November 29, 1893. During this time the party occupied 11 stations, made 20 measures each of 91 primary angles and 8 measures each of 67 secondary angles, in addition to setting and frequently testing all of the targets used.

The interval from July 5 to 11 was employed in preparing and setting targets and in collecting the necessary outfit for the party. July 12, the instrument-Troughton & Simms theodolite No. 3-was taken to west base and mounted and the angle reading proper begun.

Owing to the close proximity of the first four stations of the system to Sault Ste. Marie, the party did not go into camp until August 17, when they moved to ▲ azimuth. From August 17 to November 20, or the date on which the occupancy of A South Gros Cap was finished, the party lived in camp. On leaving South Gros Cap for Iroquois it was thought best, owing to the lateness of the season and the fact that there was a heavy fall of snow on the ground, to abandon camp and the party live with the light-keeper at Point Iroquois. Accordingly, at the request of Assistant Engineer David Molitor, my camp outfit and cook were turned over to him, he being engaged in topographic work in the vicinity, walking to and fro from his own camp, which was some 4 miles farther to the eastward.

The party finished the angle reading at A Iroquois on November 28, and on the next day moved everything to the office in Sault Ste. Marie, Mich., thus closing field work for the season.

ENG 94-214

*Not forwarded.

With the exception of a short interval, when the services of a second observer's attendant was required, owing to heliotrope work and to the necessity of packing our instruments for some distance, the party consisted of the observer, one recorder, one observer's attendant, and, while living in camp, a cook-heliotropers when required.

Mr. J. A. Holwill was recorder from July 8 to September 18; Mr. Jacob Bainbridge, observer's attendant from July 5 to September 18, and recorder from September 19 to November 29; Mr. John M. Hogarth, second observer's attendant from August 30 to September 18, and observer's attendant from September 19 to October 23; Mr. Oliver McNeely, observer's attendant from November 11 to November 29, and Mr. James Doran, cook for all of the season spent in camp. To each I desire to express my thanks for efficient service rendered.

Beginning with the base stations of the "Soo" base the primary stations occupied were: West base, east base, Soo, Ste. Marie, azimuth, Korah, Rankin Mountain, Mirron, Larke, South Gros Cap, and Iroquois. For the relative position of these stations and an idea of the primary system of the river, see sketch, p. 4350, of the Report of the Chief of Engineers, U. S. Army, for 1893.

The secondary angles read from the primary stations were to stations of the river triangulation of the improvement work, to light-houses, to church spires, and to all prominent objects of a permanent character located in close proximity to the river. The weather throughout the season was fairly good. From what I gather from the reports of the U. S. Weather Observer at Sault Ste. Marie, Mich., the conditions did not differ much from those of an average season, and up to the time when lines became so long as to require the use of heliotropes-September 1-very good progress was made. From this time forward, however, the advancement was rather slow, a good reason for which will be found by examining the weather summary for the months of September, October, and November, an extract from which is here given.

During September there were 3 cloudless, 10 partly cloudy, and 17 cloudy days; during October 1 cloudless, 7 partly cloudy, and 23 cloudy days; and during November 1 cloudless, 6 partly cloudy, and 23 cloudy days; showing that during the 3 months there were 5 days when it was certain that a heliotrope could be used, 23 days when there was a possibility that it might be used, and 63 days when it was certain that it could not be used."

METHODS.

In regard to the methods adopted in the field work it may be stated that, while we have followed in a large measure those of previous work of this character, certain changes have been introduced with a view to lessening field work and also reducing the labor of the final computations.

In this direction the number of measures made of each primary angle or the number of positions of the circle on which the angles were read, has been reduced from what is common practice in this class of work, thus lessening the time required for the occupancy of stations.

It was thought that this change could be introduced in safety, in view of the fact that the instrument to be used (Troughton & Simms theodolite No. 3) is one of a high grade, with all of the refinements required for a first-class instrument, and it is believed that the results which will be exhibited later will prove that this change was warranted.

The

In mounting the instrument at stations and in setting of targets and heliotropes no eccentric positions, with one exception, have been allowed, thus avoiding the necessity of "reductions to center" and leaving the work so that at the end of every day's observations, the observer could tell exactly the value of his results. exception noted was a target on the observatory which had to be eccentrically mounted to be seen from "Soo," for one over the center fell behind a chimney of a power house from which quantities of smoke were continually being emitted.

The usual precautions of having the instrument firmly mounted on a good support, of protecting it from the direct rays of the sun and from the wind, of seeing that all of its parts worked freely and that it was kept in good adjustment, were carefully attended to.

Measuring primary angles.-The programme followed throughout the work was to read each angle independently. The instrument having been carefully adjusted and leveled, the telescope was set on the left-hand target of any angle and the micrometers read. It was then set on the right-hand target and the micrometers again read, the difference between these readings being called a positive single result. The whole operation was then repeated in reverse order, beginning with the second target, giving a negative single result. The mean of these two results was called a combined result and is free from "station twist."

The instrument was then double reversed; that is, had its telescope turned 180° n altitude and 180° in azimuth, and a second combined result obtained. The mean