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70, through which he projected the sun's image on a screen attached to the telescope by a light framework. The telescope was the property of Mr. Barnard, and was kindly lent by him. Mr. Boscawen, at the same station, observed with an 8-inch transit theodolite; Mr. Humphries, at New Plymouth, with a 4-inch Cooke's telescope, power 200; Mr. O'Donahoo, at the same place, with a telescope, aperture 2f inches, power 110; Mr. Marchant, at Bidwell's, Wairarapa, with a 4-inch Browning refractor, focal length 66 inches, power 200, the property of Mr. David Gray, of Wellington. Captain Hewitt was also at Bidwell's with an B^-inch Browning's reflecting telescope, the property of Mr. Pope, Inspector of Native Schools. Mr. Kitson, at Christchurch, observed with a 6-inch equatorial telescope, by Cooke, the property of Mr. Townsend. . Mr. Kitson had time from Burnham, and co-operated directly with Colonel Tupman. The times given in the following table are sidereal, and are all referred to the meridian of Mount Cook Observatory. The longitude of this station is the determination given by Mr. J. T. Thomson, derived from his observations of moon culminating stars at Bockyside, Cavershani, Dunedin, in 1869-71, corrected by Sir G. B. Airy to the actual observations of the moon's distances as taken at Greenwich, and connected with Mount Cook Observatory by telegraphic and trigonometrical connection. The longitudes of the other stations are based on that of Mount Cook. The reports and details of the observations have been placed in the hands of Colonel Tupman for disposal. It would therefore be unseemly to enter on any discussion of them at present. But the general summary of them is as under :—

Geodetic. Latitude. —As will be seen from Mr. C. W. Adams's report in the Appendix, he has conducted, at the Survey Observatory, Mount Cook, Wellington, an extensive series of observations of stars north and south of the zenith for latitude, by means of the zenith telescope. In this method the constant instrumental and personal errors cancel each other, their effect on the observation of each of a pair of stars respectively north and south of the zenith being equal and opposite. Hitherto, in New Zealand, observations for latitude have been made either with reflecting instruments or transit theodolites, in both of which the altitudes of the stars are read from graduated arcs or circles. But with the zenith telescope the differences of the altitudes only are measured by means of a micrometer to the fraction of a second. The graduated circle, with its clamping and tangent screws, being thus superseded by the delicate micrometer, great steadiness is secured for the instrument, and consequently the essential condition of maintaining the instrument truly level during a set of observations is more nearly attained by this instrument than by any other. The large telescope, which the construction of the instrument permits to be used without making it unwieldy, enables stars of the sixth and seventh magnitudes to be observed with the greatest ease. There is, therefore, on every clear night, a great number of suitable pairs which may be selected from the star catalogues.

Observer. Place. Latitude South. Longitude East. Disturbance of Sun's Limb. Internal Geometrical Contact. External Contact. O F II. H. M. S. 11 39 9-58 H. M. S. 12 42 13-3 h. m. s. 12 42 22-3 h. m. s. 13 2 16-3 ames McKerrow... Boulcott Street, Wellington Mount Cook, Wellington Mount Cook, Wellington New Blymouth New Blymouth Bidwell's, Wai41 17 14 3. W. Adams 41 18 0 11 39 9-92 not observed 12 42 21-5 13 2 17-5 '. H. Boscawen ... 41 18 0 11 39 9-92 not observed 12 42 21-5 13 2 21-5 \ Humphries i. O'Donahoo . W. A. Marchant 39 4 8 39 4 8 41 11 4 11 36 22 11 36 22 11 41 46 12 42 21 not observed 12 42 27 12 42 34 12 42 30-5 12 42 38 not obsv'd. not obsv'd. 13 2 3 Japt, J. D. Hewitt rarapa Bidwell's, Wai41 11 4 11 41 46 not observed not observed 13 1 54 rarapa