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Decree of the Court.
“The system of measurement employed was that ordinarily used in the Coast and Geodetic Survey for direct measures not requiring the base apparatus.
“A narrow steel tape, twenty-five metres in length between end marks, was stretched under a tension of ten kilogrammes, as indicated by a spring balance attached to one end of the tape. The successive tape-lengths were marked on stakes driven into the ground.
“As the tape necessarily follows very closely the inclination of the ground, the horizontal distance will be less than the measured distance, and the correction for slope must be computed for each tape-length, the difference of height between the ends being determined by spirit-level. The very irregular profile of this line made these differences of height unusually great, and correspondingly increased the amount of correction.
“A small correction for catenary is also necessary when the tape swings clear of the ground, the 'sag' of the tape slightly decreasing the distance between its ends. Further, as all metallic measures vary in length with changes of temperature, it is necessary to apply a correction for such variations, the length of the tape being known at the temperature of zero, Centigrade.
"Temperatures were accordingly noted at frequent intervals, usually at every fourth tape.
“ The direct measurement was completed on May 8th, although the eastern part of the line had still to be levelled.
“The computations were at once taken in hand and the resulting distances were furnished you as rapidly as possible.
“These results, for present purposes and as compared with ordinary measures, may be considered practically exact, and they show that the chain used by the surveyors of 1850 was too long, probably from the combined effects of abrasion and of high temperature.
“ The distances between such of the old points as were recovered are nearly always too great. The ratio of excess is not constant, as, indeed, would hardly be expected, but shows a tendency to increase in going from west to east.
“A marked exception to this rule of excess in distance is found in the fifty-second mile. The eastern end of this mile
Decree of the Court.
was not recovered, but was found with reasonable certainty from various considerations, while the reputed point at the western end was recovered. The mile so determined is noticeably less than a statute mile. The western part of this mile traverses a very steep, rough, and wooded country, while its eastern part crossed the Weldon River three times in 1850.
“ These natural difficulties in the way of accurate measurement probably caused the shortage in this particular mile.
“In my own work I found it desirable to avoid the direct measurement of this mile, which is even more unfavorable now than in 1850, the Weldon having changed its course sufficiently to cross the base line five times at present.
“For this purpose a branch base about seven-eighths of a mile in length was measured on the flat ground east of the Weldon, and the distance across the broken section was then obtained with great precision by triangulation. The distances across the Grand River and Little River were also obtained by triangulation.
“Whenever in the course of the measurement we passed a point which it was desirable to refer to the base line, the point at which its rectangular ordinate met the base line was noted and the length of the ordinate itself was measured. The relative positions of these various points thus became known, including not only such of the mile points as could be identified, but also numerous objects commonly reputed to mark the boundary, as fences, trees, stones, etc.
“ As far as possible in connection with the measurement, notes were made to provide material for a topographic sketch of the strip of country traversed by the boundary.
“As stated above, the measurement was completed on . May 8th. As rapidly as the reductions were computed the places for the mile stones were marked on the ground from the fortieth to the forty-ninth.
“The weather, which up to that time bad been generally favorable, now became very wet. The frequent and heavy rains seriously interfered with the work, and rendered progress across the country very slow, the roads being nearly impassable and the fords quite so. On May 18th the exigencies of the regular work of the Coast and Geodetic Survey com
Decree of the Court.
pelled the detachment of Mr. A. L. Baldwin, who had rendered energetic and efficient assistance in the work.
“On the same day I moved from Pleasanton to Lineville to resume work on the eastern part of the line. In the intervals between rains I completed the levels, and, after computing the distances, marked the places for the mile posts, a work in regard to which further details will be given below. The topographic notes were also completed.
“In order to furnish as much information as possible in regard to this portion of the boundary line, observations for the approximate determination of the latitude and longitude and of the astronomical azimuth or bearing of the base line were made at Pleasanton and at Lineville.
“Bad weather interfered with the observations at Pleasanton, and at Lineville the lack of time and unfavorable local conditions somewhat affected the precision of the results, which answer, however, the purpose desired. Latitude and azimuth were obtained by observations on Polaris (a Ursa Minoris) with the theodolite. Time was obtained by sextant observations of the sun, using a mercurial horizon and the method of equal altitudes. For longitude the local time was compared with the railroad telegraphic time signals. It remains for me only to state briefly the old points which were recovered and the conditions which, under your decisions, governed the location of those points which were not identified by local marks.
“ The fortieth, the fiftieth and the sixtieth mile points were found marked by the iron monuments placed there by Commissioners Hendershott and Minor in 1850. There was some dispute as to whether No. 60 was in its original position or not, but the weight of evidence and the continuity of the traditional line on either side of it indicated pretty conclusively that it had never been disturbed.
“The remaining points were originally marked by stakes, sometimes witnessed.
“No. 42, while not directly identified by marks, was satisfactorily recovered by means of a “line tree' four chains W. and by topographical notes at crossing of Grand River, as shown in original record.
Decree of the Court.
“No. 44 was restored by measurement from the two witness trees, the decaying stumps of both of which were found.
“No. 49 was also identified by the stumps of both witness trees.
“No. 51 was marked by a mound and pit,' which have been accepted for years as the true marks.
“No. 54 was marked by a stone, and was further identified by one witness tree.
“No. 58 was recovered by traces of the stakes in addition to the remains of the witness tree, and the point established by J. C. Sullivan in 1816 was also found a little further east, and also the stump of an elm tree, noted as a 'line tree' in both Sullivan and Hendershott notes, being 4.10 chains W. of Hendershott's 58th mile point. The remaining points were located in the following manner:
“No. 41 was placed midway on line between 40 and 42.
“No. 43 was so placed as to preserve the relations with 42 and 44 required by the field-notes of 1850, and after being so located was found to agree with the stump of the witness tree on the Iowa side of the line.
“No. 45 was placed in the middle of the street bounding Pleasanton on the south, which middle line is shown as the boundary on the official plat of the town on file at the countyseat, and at the proper distance along the line averaging to the 49th mile.
“No. 46 was similarly located on the line passing from 45 through a stone pointed out by tradition as marking the line.
“No. 47 was placed at the proper distance on a line drawn straight from 49 westward through a witnessed section corner between 47 and 48.
“No. 48 was placed on the same line midway between 47 and 49.
“ No. 52 was located at a point west of the pond or lake in the Weldon bottom agreeing with the topographic description given by the former commissioners and on a line agreeing as closely as possible with all of the apparently authentic traces of the line surveyed in 1850.
“No. 53 was placed a mile west of 54 on the straight line between 52 and 54.
Decree of the Court.
“No. 55 was placed a mile east of 54 on the extension of the line drawn from 54 through a witnessed stone at the corner common to Wayne and Decatur Counties, Iowa.
“Nos. 56 and 57 were placed at mile distances on the straight line drawn from 55 through an iron pin at the southwest corner of the streets surrounding the public square at Lineville, which pin was universally accepted as a point marking the boundary. Unsuccessful search was also made for the remains of a wooden post which formerly stood a little further east.
“No. 59 was placed midway between 58 and 60, in the manner required by the field-notes of 1850.
“While this work was in progress many of the inhabitants along the line asked that additional points, intermediate between the mile points, might be furnished them, and with your approval this was done.
“In accordance with the decree of the Supreme Court dated January 3rd, 1851, such points were always placed on the straight line between the adjacent mile posts. The final observations were made on the afternoon of June 13th, and the instruments were then packed, and on the 15th were shipped to Washington.
“I left Lineville on June 15th, also, to resume my regular duties in the Coast and Geodetic Survey.
“In closing this report permit me to express my appreciation of the uniform courtesy and consideration shown my assistant and myself by all the members of the commission, and my hope that our earnest labors in this interesting work have proved satisfactory in methods and results, and that they may be instrumental in permanently settling this controversy.
“The appended pages give in summarized form the results of the observations and measurements, as well as the mathematical formulæ employed. “Respectfully submitted.
“W. C. HODGKINS, “ Assistant, Coast & Geodetic Survey, Chief of Party.”
“ APPENDIX A. “The following table gives the bearings and distances between the successive mile posts of the Missouri-Iowa boundary