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heading at the top of the page, by means of which they will be readily found on the sketches accompanying the tables. Sub-headings in the first column indicate the locality more minutely where it is practicable.
The stations are generally either prominent objects of permanence, such as spires, light-houses, beacons, &c., or they are the points on prominent hills, capes, or points of land, where signals have been erected for the purpose of the survey, and which are marked on the ground. In a small number of cases in the first three Sections, but much more frequently in the southern Sections, where settlements on the coast are sparse, and few permanent objects are to be found, the stations have no other distinguishing mark than the signal erected on the spot; and after its decay, the mark left on the ground, to designate the station point. The latter generally consists of posts or stones set around the point, while the centre of the station is designated by an earthen cone or glass bottle buried under the surface of the ground and marked on top by a stone or post. Where the station is on a rock, a copper bolt, or a hole filled with lead or sulphur, will be found to designate the exact spot.
The sketches showing the configuration of the land, as well as the relative positions of the stations, no great difficulty will be experienced in finding the latter, when desired for local surveys or reference. In any case where minute descriptions of particular points are required, they can be had by application addressed to the Coast Survey office.
The second and third columns contain the latitudes and longitudes of the stations named.
The fourth column contains the azimuth of the line joining the station named in the first column to that named in the fifth; that is to say, the angle which that line makes with the meridian of the former station, reckoned from south around by west, through the whole circle. The sixth column gives the back azimuth of the same line, or the angle which it makes with the meridian of the latter station, reckoned as before; the difference between the azimuths in the fourth and those in the sixth columns being 180°, less the inclination of the meridians at the two stations.
The seventh, eighth, and ninth columns give the distances, in metres, yards, and iniles, between the stations named in the first and fifth columns. The relation of the metre to the yard used in obtaining these results, is1 metre=1.0935696 yard, or 39.36850 United States standard inches.
For each station the azimuths and distances to two other stations are given. In every case the lines so given have actually been observed.
In each section the stations of the primary triangulation are given in a separate table, in which all the distances and azimuths observed are given. Whenever these primary stations afterwards occur in the columns of the general table, they are distinguished by being printed in small capitals.
Those points which are marked with an asterisk have been determined by means of the plane-table; their positions are not as accurate as those of the trigonometrical points, and are liable to be in error about three metres, or ten feet.