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their ordinary duties, that can exist in the bosoms of those only who have a heart for their work.
A considerable mass of unemployed material, connected with subjects of general interest, has been confided to me by scientific and other intelligent men in various parts of the Colony; but I defer more particular mention until a second volume of the series shall appear.
A copious Index is to be found at the end; and reference is recommended to it on every occasion when the reader wishes to learn all that is contained in the work respecting any given subject.
Very great pains have been taken to secure the closest possible accuracy throughout the book; yet some errata have been discovered, which are noted on the last page. It is hoped, however, that no error of moment has escaped observation. At all events, criticism is invited, and every practical suggestion for the improvement of any portion will be duly and thankfully acknowledged, come from what quarter it may. The whole compilation has been a labor of love; and whatever tends to increase its worth will be a subject of welcome.
WILLIAM HENRY ARCHER.
Registrar General's Office,
Melbourne, 21st September, 1854.
EVER Since the settlement of Port Phillip as a District of the Colony of New South Wales to the present time, when it has become known as the Golden Colony of Victoria, great doubts have been expressed by many nautical men as to the true geographical position of Melbourne, its capital city. During the whole time that the Survey Department was under the management of Mr. Hoddle, the late Surveyor General, the latitude and longitude of Batman's hill were received and computed from, as being latitude 37d. 49m. 23s. south, and longitude 144d. 58m. 15s. east of Greenwich, or 9h. 39m. 53s. in advance of Greenwich mean time. Vessels sailing direct from Europe, and making the Heads of Port Phillip Bay from the westward, have in general found that the above difference of longitude was too great. Most of the commanders of ships who mainly depended on their chronometers, and found a difference, appear to estimate the difference as being from seven to nine miles; but hitherto no precise intimation has been given that Melbourne was to the westward of its received position.
On the 6th of December, 1853, C. J. Tyers, Esq., Commissioner of Crown Lands for Gipps' Land, whose qualifications as a land and marine surveyor are of the first order, forwarded to His Excellency C. J. La Trobe, Esq., a memorandum respecting a survey of part of Gipps' Land by Messrs. Nevens and Wilkinson, which he had been requested to superintend, in which he makes the following statement:—
"The longitude of Mount Singapore has been assumed 146d. 27m. 30s., being three-quarters of a mile less than is assigned to it by Captain Stokes, R.N., that officer having measured from the meridian of Fort Macquarie, Sydney, which he assumes 151d. 16m., but which, in the determination of the boundary between New South Wales and South Australia, or the 141st meridian, I assumed as 151d. 15m. 15s. Upon this all the longitudes given by me in Gipps' Land, and between Melbourne and the mouth of the Glenelg, depend. The longitude of Fort Macquarie, and thence of Batman's Hill, may be deduced from the following results :
Proceedings Ast. Soc., vol. vi., p. 203. Parramatta, 151d. 1m. 48.25s. +
Sir Thos. Brisbane (N. A.), 10h. 4m. 6.25s., or 151d. 1m. 33-75s. +13m. 13.05s.
Eclipse of the sun (1st Feb., 1851), observed by Captain Kay, at Hobart
Tyers' distances of sun and moon, and of moon and stars, Port Essington,
Tyers' distances of sun and moon, and of moon and stars, Portland Bay,
D. M. S.
151 15 1.3
151 14 46.8
151 13 46-49
151 14 11.10
151 15 10
151 15 14-0
151 14 21
Captain Stanley's moon culminating stars, observed at Port Essington;
151 18 57
151 14 54
Captain King's moon culminating stars, observed at Tahlee; reduced by
151 15 30
Captain King's eclipse of the sun, and of Jupiter's satellites, and occulta-
"This result may be considered a very close approximation to the truth, and should,
I think, set at rest all doubt as to the longitude of Fort Macquarie.
"Using the mean of Captain Stokes' and my own meridian distance between Sydney and Batman's Hill, 6d. 16m. 9s., thus
"The longitude of Batman's Hill is 144d. 58m. 35s. east, being 30s. less than assumed by me in 1839, which should be subtracted from all my longitudes."
The year 5616 of the Jewish Era commences on Thursday, 13th September, 1855. The year 1272 of the Mohammedan Era commences on Thursday, 13th September, 1855.
Ramadân (the month of Abstinence observed by the Turks) commences on Friday, 18th May, 1855.
In the year 1855 there will be two eclipses of the sun, and two of the moon.
1. A total eclipse of the moon, invisible in Victoria; begins on Wednesday, 2nd May, at 52 minutes past 10 in the forenoon, and ends the same day at 38 minutes past 4 in the afternoon.
2. A partial eclipse of the sun, invisible in Victoria; begins on Wednesday, 16th May, at 43 minutes past 9 in the morning, and ends the same day at 39 minutes past 1 in the afternoon.
3. A total eclipse of the moon, partly visible in Victoria; begins on Thursday, 25th October, at 25 minutes past 2 afternoon. The moon will rise partially eclipsed in Melbourne before the end of the eclipse, which will terminate on the evening of the same day, at 53 minutes past 7 o'clock.
4. A partial eclipse of the sun, visible in Melbourne and other southern parts of Victoria, Saturday, 10th November
Begins on the earth generally 3h. 15m. A.M., in long. 171d. 38m. east of Greenwich, and lat. 31d. 21m. south.
Greatest eclipse, 4h. 57m. A.M.; magnitude (sun's diameter 1) 0·494, in long. 121d. 5m. east of Greenwich, and lat. 62d. 37m. south.
Ends on the earth generally 6h. 39m., in long. 2d. 34m. east, and lat. 68d. 52m. south.
The mean obliquity of the Ecliptic on January 1, 1855, is 23d. 27m. 29.67s.; and its mean annual diminution is 0.457s.
The semi-diameter of the sun at the earth's mean distance is 16m. 1.82s., being the result of twelve years' observations (from 1836 to 1847), made at the Royal Observatory, Greenwich.
The equatorial horizontal parallax of the sun at the earth's mean distance is, according to Professor Enke, equal to 8.5776s.
The constant of Aberration is 20.42s.
The sun is in perigee on Tuesday, January 2nd, 1855, at 59 minutes past 6 in the morning.
The sun will also be in apogee on Monday, 31st December, 1855, at 12 minutes past 10 at night.
The seasons are as follows:
March 21d. 1h. 48m. P.M., the sun enters Aries-Mid-Autumn.
Each differing from those adjacent by One Minute of Time, and adapted to the Parallel of Melbourne, 37 deg. 49 m. 238.
The above table is constructed thus:-To the log. tangent of the latitude add the log. tangent of the declination, and from the sum subtract 10. The residue is the log. cosine of an arc, which must be divided by 15 to convert it into time, and is the semidiurnal arc corresponding to the declination used in the computation.
The great advantage of semi-diurnal arcs is, that they enable us, almost by a simple inspection, to determine approximately the rising or setting of the celestial bodies. Thus, in the case of the sun, the numbers in the table show the time from noon when that body rises or sets, provided the declination and latitude are both north or both south; but if the one be north and the other south, then the tabulated semi-diurnal arc must be taken from twelve hours to find the required time from noon of the sun's rising and setting.
In order to find the time when a planet rises or sets, we proceed, as in the case for the sun, to find the semi-diurnal arc; after which, having found the planet's meridian transit, as given in the Almanac, we subtract the semi-diurnal arc (found as already directed), which leaves the time of rising; and by adding the same arc to the time of the meridian transit, we find the time of setting.
To find the time when a fixed star rises or sets, we find, as before, the semi-diurnal arc corresponding to the latitude and declination, and then find the time of the star's meridian transit, as follows:-Take from the Almanac the right ascension of the star and also of the sun, and when the right ascension of the star is less than that of the sun, increase that of the star by twelve hours, and from the sum subtract the right ascension of the sun what remains is the time of the star's meridian transit, to which apply the semi-diurnal arc, which will give the time of rising or setting required.
TABLE OF THE SUN'S DECLINATION AT MELBOURNE, MEAN NOON, FOR EVERY MONTH AND DAY IN 1855, TO THE NEAREST ONE-TENTH OF A MINUTE.
Days. JANUARY. FEBRUARY.
AUGUST. SEPTEMBER. OCTOBER. NOVEMBER. DECEMBER.