Marshall Bay. September 3, 1853. According to p. 390, vol. II. of the Narrative, this station is from bearings 1° 59' east of the winter quarters, and hence in longitude 68° 54'. Rate of chronometer about 28.5 gaining daily; error, September 12, on Fern Rock mean time-4h 43m 26s. Theodolite observations. Circum-meridian altitudes of the sun, for latitude.

On account of the uncertainty in the chronometer error it was considered safer to use the first combination alone, as being nearest to true noon.

Determination of the elevation of station on Marshall Bay by means of the depression of the sea horizon. Observations with the theodolite.

Using 0.08 for the co-efficient of refraction, the corresponding elevation is 27.8 metres or 91 feet.

The following record of determinations of latitudes, by various travelling parties, has been copied from volume II. of the Narrative, Appendix Nos. V. and VI.

Cape John Frazer, position XXIII, May 28, 1854.

This position is determined by an observation with sextant and ice horizon.

The determination of the latitude of Cape Hawks, position XV., does not agree with its location on the map, it is therefore here omitted.

Cape William Wood, position LXXI, June 7, 1854.

(The data given on page 383, vol. II. of the Narrative, for longitude of the two last stations, are insufficient; the resulting longitude, as given on the map, must therefore be adopted. The index error of the sextant has been applied to the observations of the preceding three stations.)

Littleton Island, June 12, 1855.

The latitude of Littleton Island is determined by a set of circum-meridian altitudes of the sun, made on the east end of the island; the individual observations give (when corrected for refraction)—

This position is obtained by an observation at a point on the ice five miles distant and N. 7° 26' E. (true) from the cape.

The map appended to this paper is based upon the preceding astronomical results; the astronomically determined positions (either in latitude or longitude) are indicated by a star; for its longitudes, it depends on the well determined meridian of the winter quarters; the detail of shoreline and the principal names are from Dr. Kane's map, in vol. I. of the Narrative. The projection depends on the following data, derived from Bessel's elements of the figure of the earth.

Examining the original map in the Narrative, I found that the longitude of the Observatory in Van Rensselaer harbor actually adopted was not that given in the text, but a value so nearly agreeing with my final result, that no change in the longitude of that part of the coast was required in the transfer of the shoreline to the new map. By request, Mr. Sonntag marked the exact position of the observatory

in reference to the shoreline of the harbor, an important datum, not given before. It will be perceived that the only change of importance made in the present map, is the shifting of the shores of Kennedy Channel to the southward to an amount of about nineteen nautical miles; it is well known that Dr. Kane had adopted the mean positions resulting from astronomical observations and dead reckoning, whereas in my map the astronomical determinations alone have been used. This change I made with the concurrence of Professor Bache, who, in May, 1858, communicated to the Royal Geographical Society, in England, that such a step seemed desirable and proper. The highest point of the shoreline, traced by Morton, on the east side of the Channel, is now placed in latitude 80° 56', and, on the opposite side, the highest point distinctly seen by him is located in latitude 82° 07′.1 The following table contains the geographical positions of stations determined by travelling parties, and the latitudes of which have been given above.

The following results are taken from a report of Mr. Sonntag's to Dr. Kane, dated September 12, 1855 (at Godhavn).

(NOTE. In my discussion of the magnetic observations of the expedition the latitudes and longitudes of the stations could only be given approximately, and the results now obtained should be substituted instead of them.)

Observations in Connection with Twilight.-The following notes, made by Dr. Kane, has been extracted from his Log-Book. In calculating the sun's depression below the horizon, I have applied a correction for horizontal refraction, taking into account the temperature actually observed on that day.

Oct. 15, 1853.-Last entry of sunlight having been seen. "Astronomically, the upper limb of the sun should disappear at noon, October 25, if the horizon was free, but it is obstructed by a mountain ridge."

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1 In a letter (dated Albany, February 29, 1860), Mr. Sonntag expresses himself as follows: "I am very glad to learn that you are going to reconstruct the map, and to reduce the upper portion of it, and I feel confident that, after the reduction is made, it will have claims to as much accuracy as any other map of any parts of the Arctic Regions."

2 Page 105, vol. I. of the Narrative.