RECOMMENDATIONS. For future topographical surveys in this region I would respectfully recommend the following organization of topographical party : One assistant engineer in charge. Two recorders, to be men capable of running the plane table and to be fair drafts men. Five rodmen, to be young men of sound physique, who are preparing for the profession or have had previous experience as rodmen. One head axman, to be capable to take charge of laborers and to understand the use of reconnoitering instruments, and act as head rodman on a transit survey. Two axmen, and at times such additional number of axmen as the work may require; these men to be woodsmen, preferably of the region the survey is operated in. This party to be equipped with the following instrumental outfit: Instruments.-One transit, 1 Y-level, 2 plane tables, and such additional instruments as are fund of service in reconnoitering. The methods to be employed I would recommend to be as follows: Plane table field sheets of the reach to be surveyed during the season should be fully prepared before the party takes the field, with all bench marks, tertiary, secondary, and primary triangulation stations plotted thereon. The assistant to plan the work for the two plane-table parties and for the advance chopping of necessary traverse lines, and to locate by additional triangulation and leveling such additional reference points and bench marks as it may be found desirable to establish in order to have no such points originated by plane table alone. The recorders to secure all needed topographical information by plane-table surveys from these fixed and plotted points, always orienting the plane table by intersection or resection upon points plotted on the sheet. Each plane-table party to consist of the recorder in charge, 2 rodmen, and 1 axman, who is to carry the plane table. The head axman is to take charge of the chopping needed to clear lines for survey on shore, hill range, roads, and traverse, with such additional axmen as could be employed at intervals for short periods; at other times he would be available with the fifth rodman to form a transit or level crew for the assistant in charge. He is also to take charge of the camp property and tools, and of camp policing and moving of camp. The salary of such a party on the scale recommended for the coming season, together with salary of 4 additional axmen employed for ten days during each month, and the subsistence on the ratio of last season's cost, would amount to a total about 20 per cent less than the total cost of the two topographical parties last season, while in my estimation such an organization would be capable of accomplishing as much and probably more field work than the two parties did together during the past season. A not inconsiderable saving in time and expense could be secured, in my opinion, by arranging to have the cook and mess outfits of the entire party located on a flatbottomed scow, which could be easily moved at any time without necessitating the packing and unpacking of all the utensils on the occasion of each move. More frequent moves of camp could be had and thereby walking to and from work reduced and more time utilized in actual field work. With this arrangement it would be perfectly practicable to have the head axman, with assistance of additional axmen, move the entire camp and relocate same while the field parties were doing their customary field work. PART II. MAPPING, CHARTING, SKETCHING, ETC. After completing the platting and inking of the last transit field work and converting field sheet No. 2 (Big Point to Solomons Point) from St. Marys River level data, to New York tide level data, my office work during period from December, 1893, to June 30, 1894, consisted, as outlined in your letter of instructions dated January 16, 1894, of First. Special drafting work required by you from time to time. Under this head I constructed (1) A general map of primary triangulation scheme of St. Marys River from line Gargantua-Mamainse to the Mackinac base, scale 1: 380160; (2) A similar plan of primary and secondary triangulation of same reach, scale 1:380160; (3) A sketch of conventional signs for topography and hydrography; (4) An outline sketch of chart No. 3, St. Marys River survey, with scheme of sounding lines for ice survey, scale 1: 40000; (5) A similar outline sketch of chart No. 2, St. Marys River survey, scale 1: 40000; (6) A general outline sketch of chart No. 1, St. Marys River survey, scale 1:40000; (7) A general outline sketch of a chart of Whitefish Bay, scale 1:80000. Second. The duplication of all field work done by the topographical parties, which necessitated the tracing of sheets Nos. 1, 2, 3, and 4 of the Canadian shore survey. Third. The preparation of an accurate field plat of Sault Ste. Marie, Mich., on a 1:5000 scale, which absorbed about two months of time devoted to the securing of all available reliable data relating to streets, subdivisions, buildings, etc., from public records, previous surveys, existing maps, and from personal reconnoissance. Fourth. The preparation of a scheme for the polyconic projection of the reach covered by chart No. 3, on a 1:40000 scale, and of its subdivision into suitable uniform sheets showing both shores of river with hydrography on 1:10000 scale. The general scheme and two of the sheets were completed. The first one, covering the reach from Big Point to Little Rapids and including Sault Ste. Marie, Mich., and Canada, with all the details previously secured, occupied about two months of my time; the second sheet, covering the reach from Old Vessel Point, Canada, to Point aux Pins, was also completed. Fifth. The preparation of a similar general and subdivision scheme for reach covered by chart No. 2, of which the general plan only was completed. Very respectfully, your obedient servant, First Lieut. CHARLES S. RICHÉ, H. VON SCHON, Corps of Engineers, U. S. Army. G.-REPORT OF MR. DAVID MOLITOR, ASSISTANT ENGINEER. UNITED STATES ENGINEER OFFICE, Detroit, Mich., May 14, 1894. SIR: I have the honor to submit the following final report relating to operations of the survey party under my charge, July 10 to December 1, 1893, while resurveying the Canadian shore of St. Marys River, between the Shingwauk Home and North Gros Cap. NARRATIVE. In accordance with the order of Col. O. M. Poe, Corps of Engineers, dated Detroit, July 10, 1893, I reported for duty at Sault Ste. Marie, Mich., on July 12, 1893. The remainder of the month of July was devoted to the preparation of camp outfit, office work, etc. From August 1 to 3 I carried a line of levels from B. M. "A" on the north wall of the '81 lock at Sault Ste. Marie, Mich., across the international bridge and east along the Canadian shore to a point opposite Topsail Islands. On August 4 I was ordered to cut lines of sight for triangulation work, from A Azimuth to A Soo, A Larke, and A Mirron. This was done by day's labor, and was completed on August 11. The plane tables with which the topographical work was to be done arrived on August 7, and I proceeded at once to graduate the stadia rods for the two parties. The party in charge of Assistant Engineer H. von Schon being in the field, it was deemed Lore practicable for me to do this work. My party was accordingly organized, and went into camp on the Canadian shore, opposite Topsail Islands, on August 14, 1893. The party consisted of the following members: John Conrick, recorder, in the service from July 12 to December 9, 1893; Clifton R. Norton, rodman, in the service from August 1 to September 13, 1893; Richard Johnson, rodman, in the service from August 7 to December 1, 1893; Fred E. Leefe, rodman, in the service from August 10 to September 30, 1893; W. J. Steere, rodman, in the service from August 10 to December 1, 1893; Peter Biron, cook, in the service from August 10 to October 1, 1893. Subsequent changes caused the following to be employed: Peter Biron, rodman, in the service from October 1 to November 24, 1893; C. E. Thompson, rodman, in the service from September 19 to December 1, 1893; Mrs. Peter Biron, cook, in the service from October 1 to November 22, 1893. The first camp, near Topsail Islands, was occupied until September 1, and an area of about 5 square miles, including the greater portion of the town of Sault Ste. Marie, Ontario, was covered. As may be inferred, this work contained considerable detail, which, together with a newly organized party, made the progress rather slow at first. The second camp was pitched on Davignons Point, and was occupied until September 29, having moved camp with the tug Myra. An area of about 9 square miles was surveyed from this camp, including the western portion of Sault Ste. Marie, Ontario, the Canadian canal grounds, Swedish settlement, and the country about 4 miles west of the town. A line of levels was also carried from a bench mark near the Canadian Lock, previously established, to a bench mark on Dick Moores Point. The third camp was located between the Big and Little Carp rivers, about one-half mile from shore. Moving from Davignons Point was done by team and wagon. The area covered from here was about 11 square miles. More work was done from this camp than would ordinarily have been advisable, but for several reasons it was considered best to survey the Point aux Pins region from here, and not to occupy this locality with a camp. The more important reasons leading to this conclusion may be thus stated: According to orders, the survey was to extend north as far as the bluffs, and this necessitated an inland camp. As there is only one road, which is very bad in places, leading from Point aux Pins to the north, and as the bulk of the work was done at some distance inland, it was thought best to complete the shore line and the lower portion of marshy country while being located at the Carp River camp, and then to move camp by wagon to the second line road, which was done October 23. On October 9 and 10 I continued the levels from a bench mark on the base line road, previously established, to about one-half mile east of Gros Cap, at the Indian settlement. The plane table being the only instrument available up to October 12, was used exclusively previous to this time. The weather was becoming very disagreeable, cold and rainy, so that the plane table was entirely abandoned as soon as a transit was placed at my disposal. Since October 12 the plane table was used only three days, during exceptionally good weather, on shore line work. The camp No. 4, on the second line road, was occupied from October 23 to November 14. During this time the party lived in a vacant house which they had rented, in preference to camping in tents. The plan was a good one, as there was much rain. It kept the men in excellent health. About 13 square miles were covered from this camp, completing the survey to South Gros Cap. At this time continual snowstorms made the progress very slow, but the work was nevertheless continued to North Gros Cap, in compliance with the orders received. This necessitated moving camp to South Gros Cap on November 14, and working as the weather permitted. The larger portion of my camp outfit was moved to Sault Ste. Marie, Mich., via Point aux Pins, in sleighs, and the party took possession of Assistant Engineer Haskell's camp, as Mr. Haskell was no longer in need of his outfit. The continued snow made the traveling very slow on the Gros Cap ridge, and as the country is thickly wooded there was much cutting to do, so that this work, covering only about 2 square miles, was not completed until November 28. Messrs. John Conrick and C. E. Thompson walked to Sault Ste. Marie, Mich., to report the completion of the work and that camp should be moved. The first opportunity for the tug Myra to land at Gros Cap occurred on December 1, when the remainder of the party and the outfit were brought back to Sault Ste. Marie. The trip was very stormy, and one of the tents was blown overboard and could not be recovered. The plotted and inked field sheets, numbered 1 to 5, together with notebooks comprising the records of the survey, were filed in the office at Sault Ste. Marie, Mich. The party was discharged and I returned to Detroit in obedience to a written order from Col. O. M. Poe, reporting for duty in Detroit on December 3, 1893. METHODS. The plane table with stadia was used exclusively from August 11 to October 12, it being the only good instrument provided for this work. From October 12 to completion of the survey, November 29, a transit and stadia was used, with the exception of three days. This transit had been used by Assistant Engineer E. E. Haskell on the triangulation work, and became available just at the time the cold and wet fall weather set in, and the plane table would necessarily have been discarded. While working with the plane table the various duties were distributed among the members of the party as follows: The chief of party did the field plotting and took the station settings, directed the rodmen, and planned the general course of the work, besides looking up any doubtful matters. The recorder took the instrument pointings for side shots, recording all readings in his notebook, while the chief would plot the readings and number the points as recorded, so that it was possible to identify each plotted point in the notes. Three rodmen did the regular rodding work and the fourth carried the plane table. Of the three regular rodmen the best man was selected as head rodman, the second best as side rodman, and the less competent as rear rodman. The man showing the least aptness was detailed to carry the instruments. The field platting was done in pencil and the sheets were executed in ink during rainy weather and evenings. These field sheets formed a complete record of the work, showing all fences, boundaries, shore line, waterways, dwellings, and all other topographical features of the ground, including 20-foot contour lines. The notes, which contained only the data for finding the elevations of the contour points, were worked up at night by the recorder, and the elevations were then written on the field sheet. When sufficient area had been covered in this manner the contours were drawn. This method was found to be the most expedient when taking 20-foot contours on a scale of 1:10000. It might be mentioned, however, that on very detailed work in mountainous country, where, say, 5-foot contours may be required and the work is platted on a large scale, it would be best to change the above programme and compute the elevations with a slide rule while on the ground and draw the contours before leaving a station. This method is necessarily much slower, and though it was first adopted, it was soon abandoned and the notes were worked up in camp. A more detailed account of the manner of doing plane-table work may not be out of place, and may be useful in future work on St. Mary's River. The plane table was used much in the same manner as a transit in doing stadia work. A field sheet was commenced by locating upon it one of the lines of the tertiary triangulation system, for example, the course A A-AB, having previously decided upon the area of country to be covered by such a sheet, so that the line could be correctly drawn. This was usually done in camp. One of these stations, as A A, was then occupied, orienting the table on the line A-B, and shots drawn to all visible stations and prominent objects. The other station AB was then occupied with the instrument oriented back on the line A-B, as before, and shots drawn to the same points as from the AA. This then located all the objects sighted, by intersection, assuming that the line A-B was correctly measured off on the field sheet. Such preliminary preparation forms a basis for checking all subsequent work on the sheet, and also affords means to locate the position of the instrument when placed at any point in the field. The filling in of details on a sheet thus prepared was done precisely as it would have been with the transit and stadia, only that each point was platted immediately in the field and all details were drawn before leaving the ground. It was made a practice to run polygonal lines between the points previously determined, thus checking both the original points, as determined by intersection, as also the polygon. In this way it was scarcely possible to introduce any error in the work. The transit and stadia was used in the same manner as was done on the Mississippi River Commission survey, and the work was platted in camp and inked in the same manner as the plane-table sheets. RECOMMENDATION REGARDING METHODS TO BE FOLLOWED IN FUTURE WORK. The comparative utility of the plane table and transit depends entirely upon the character of the topography and the weather. The plane table can be advantageously used only in open country and during dry weather. Strong wind is a hindrance. The transit can be used in any country and in any weather in which men can work. In open country, where there is much detailed topographical work, I should say that a party could cover about the same area, in the same time, with either instrument; but the plane-table work would be platted, while the transit work would not. In wooded country, or such localities where there would be comparatively few side shots, the transit has decided advantages, it being a much lighter instrument, especially adapted to quick settings, and requiring no such care as is necessary to prevent the field sheet from becoming soiled or injured. As may be supposed, my party was considerably delayed between August 14 and October 12, the work being confined to weather which would not injure the planetable sheets. I have estimated a loss of about twelve days between the dates just mentioned, on which transit work could have been done perfectly well; but having no other instrument, this time could not be utilized for field work, and the men were employed in the best possible manner preparing for future work. This time, therefore, was not an actual loss; yet the field work, which represented the real progress, was delayed. This was the best part of the season, an 1 between October 12 and November 30, there were only fourteen days which would have permitted the use of a plane table, while with the transit only eight days were lost on account of severe rain and snow storms. It would seem, then, that a party ought certainly to be equipped with a transit, and, if practicable, to be provided with a plane table to be used when opportunities are offered. I should also recommend, if new transits be purchased for future work, that these possess some of the features of the Buff & Berger plane table, that is, be provided with a telescope which can revolve on its optical axis, making the adjustment for collimation similar to that of a Y-level. The level should also be a detachable striding level as provided for the plane table. This will make the transit suitable even for running accurate levels. The tangent screw for the horizontal movement of the plane table is a defective mechanism, for it produces a lost motion in the screw and the ball and socket joint. This movement should be carefully avoided in future instruments. The only perfect mechanism of this kind made up to this time is the movement which Messrs. Buff & Berger make for their transits. It would be advantageous to have one or more of the stadia rods made to read 500 meters, instead of all to 400, as there is often great advantage in being able to read long station distances. It might also be suggested that the rates of pay of the party be changed more in proportion to the duties imposed, and the following would seem a fair disposition to make: As the progress of the work is greatly dependent upon the efficiency of the head rodman and recorder, these inen should be carefully selected and should possess a full knowledge of the work. The best men for this purpose are young engineer students. A fair knowledge of drawing is almost indispensable to the recorder, especially while doing plane-table work, as he is called upon at times to take the place of the chief, or do independent work when both transit and plane table are being used simultaneously. If future work is to be done on a larger scale than last summer's, it might be advisable to provide two recorders, both of whom should be capable of doing instrumental word. Such a party ought to be supplied with one rear and one head rodman in addition to the above personnel. Both instruments might then be employed in the field and each used to its best advantage. STATISTICS. Amount of work done.-In attempting to state the amount of work done the only data which conveys a reasonable impression is the area covered, yet this is very unsatisfactory, as the amount of work necessary to survey a square mile of country differs very widely. So, for instance, the vicinity of Sault Ste. Marie, Ontario, requires vastly more detailed work than does the open marsh meadow on Point aux Pins. During the season's work an area of 40 square miles was surveyed, containing a developed length of shore I ne of 38.7 miles. Of this area 17 square miles were surveyed with the plane table in 35.5 working days, and 23 square miles with the transit and stadia in 29 working days, making a rate of 0.48 square mile per day with the plane table and 0.65 square mile per day with the transit. The whole time spent in the field was 109 days, of which 35.5 +29=64.5 days were spent in actual field work. The time lost to field work 109-64.5-44.5 days, is accounted for as follows: Sundays Moving camp Loss by rain while working with the plane table Days. 16 6 14.5 8 Loss by rain and snow storms while using the transit.. Total.... 44.5 Cost of work. The following are the expenses incurred in equipping my party and surveying the above area on the Canadian shore of St. Marys River, between the Shingwauk Home and North Gros Cap, between the dates July 1 and December 1, 1893: ENG 94-215 |