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(Abstract.)
The instrument used for the observations to obtain the longitude at the Hutt Observatory, as given in the accompanying table, is a 24-inch transit of a new construction, by Troughton and Simms. The standards are half-moon shaped and hollow, two inches radius at the base and tapering slightly towards the Ys; they are fixed on a massive brass plate which rests on three levelling footscrews. The telescope has five transit wires and a right ascension micrometer wire, the cylindrical head of which is divided in 100 parts, each indicating 0′61. The axis level has a scale graduated into divisions of 1′ value. The finding circle is six inches in diameter, and fixed to one of the pivots; it is read by two verniers.
The instrument is mounted upon a brick pier, built with Portland cement, and sunk 5 feet below the surface of the ground. The pier is 5 ft. 6 in. square at the base, it rises in a pyramidal shape to the level of the floor of the building, where it is 2 ft. 4 in. square, it is then carried up square to a height of 4 feet above the floor; it is completely isolated from any contact with the ground or floor of the building from its base.
The building is octagonal, 7 ft. 6 in. across, and has a roof revolving on eight cast iron wheels upon a circular ring of angle iron. The shutters, one north and the other south, are 1 foot in breadth; they open upon hinges and expose the meridian from horizon to horizon.
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In conclusion I would remark, that if similar observations were conducted for a year or two at the various stations in New Zealand in communication with the electric telegraph, and at which transit instruments have been mounted for the determination of local time, the
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combined results of the observations of different persons would furnish a most reliable initial longitude. The method of using a corrected Ephemeris, instead of depending on actual observations at Greenwich for differences of right ascension, has in my opinion advantages for New Zealand, since about 60 per cent. of the moon's meridional transits are lost through unfavourable weather.
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| Longitude. | |||||||
|---|---|---|---|---|---|---|---|
| No. | Date. | Moon's linub. | H. | m. | s. | Probable errors. | Weight |
| 1 | June 9 | I | 11 | 39 | 39.95 | 5.9 | 0.747 |
| 2 | May 11 | I | " | " | 44.89 | 5.8 | 0.773 |
| 3 | July 19 | II | " | " | 45.41 | 7.3 | 0.488 |
| 4 | July 5 | I | " | " | 45.45 | 6.1 | 0.699 |
| 5 | July 7 | I | " | " | 45.58 | 6.0 | 0.722 |
| 6 | Sept. 4 | I | " | " | 46.45 | 5.3 | 0.926 |
| 7 | July 10 | I | " | " | 47.20 | 5.2 | 0.962 |
| 8 | Aug. 6 | I | " | " | 47.32 | 5.4 | 0.892 |
| 9 | July 13 | II | " | " | 47.37 | 5.4 | 0.892 |
| 10 | May 7 | I | " | " | 47.45 | 6.0 | 0.722 |
| 11 | June 16 | II | " | " | 48.05 | 5.6 | 0.829 |
| 12 | July 6 | I | " | " | 48.67 | 6.1 | 0.699 |
| 13 | July 16 | II | " | " | 48.94 | 6.5 | 0.616 |
| 14 | July 9 | I | " | " | 49.19 | 5.7 | 0.801 |
| 15 | Aug. 11 | II | " | " | 49.47 | 6.2 | 0.677 |
| 16 | Oct. 6 | I | " | " | 49.57 | 6.6 | 0.598 |
| 17 | Oct. 15 | II | " | " | 51.21 | 6.2 | 0.677 |
| 18 | June 18 | II | " | " | 51.40 | 6.4 | 0.635 |
| 19 | Oct. 9 | II | " | " | 51.54 | 7.2 | 0.502 |
| 20 | Oct. 14 | II | 11 | 39 | 51.62 | 6.4 | 0.635 |
| 21 | June 14 | II | " | " | 52.01 | 5.2 | 0.962 |
| 22 | May 17 | II | " | " | 52.15 | 5.1 | 1.000 |
| 23 | Oct. 5 | I | " | " | 52.98 | 6.2 | 0.677 |
| 24 | Aug. 9 | I | " | " | 53.08 | 5.4 | 0.892 |
| 25 | Sept. 3 | I | " | " | 53.54 | 5.5 | 0.860 |
| 26 | Aug. 7 | I | " | " | 53.97 | 5.4 | 0.892 |
| 27 | Sept. 9 | I | " | " | 54.60 | 6.7 | 0.579 |
| 28 | Oct. 3 | I | " | " | 55.12 | 5.6 | 0.829 |
| 29 | Aug. 13 | II | " | " | 55.18 | 6.7 | 0.579 |
| 30 | June 21 | II | " | " | 55.72 | 7.3 | 0.488 |
| 31 | July 18 | II | " | " | 56.93 | 7.2 | 0.502 |
| 32 | July 20 | II | " | " | 56.02 | 7.2 | 0.502 |
| 33 | Sept. 2 | I | " | " | 56.18 | 5.5 | 0.860 |
| 34 | Sept. 7 | I | " | " | 57.01 | 5.9 | 0.747 |
| 35 | Oct. 7 | I | " | " | 57.56 | 7.0 | 0.531 |
| 36 | Oct. 9 | I | " | " | 57.88 | 7.3 | 0.488 |
| Mean Longitude by weights | 11 | 39 | 50.73 | 1.0 | 25.860 |
15. “Notice of a new form of Cetacean Tooth,” by Dr. Knox. (See Transactions.)
16. “Notes on the Chatham Islands and their Inhabitants,” by Major Gilbert Mair; communicated by His Honor W. Rolleston, Superintendent of the Province of Canterbury. (See Transactions.)
17. “On the absence of the Eel from the upper waters of the Waiau-ua and its tributaries,” by W. T. L. Travers, F.L.S. (See Transactions.) In this paper the author attributes the absence of the Eel from the district in question, to the necessity for its migration to the sea, or to the warmer parts of the river, during the spawning season, and the inability of the fry, or even of the adult fish, to re-ascend the river beyond a certain line of rapids referred to.
18. “Notes upon a New Zealand Flesh-fly,” by W. T. L. Travers, F.L.S (See Transactions.) The author describes, in this paper, the “Blue-bottle-fly” common to New Zealand, which he considers is indigenous, and not introduced into this colony as is generally supposed.