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DAYS imbued with a portion of their beauties, and his literary productions helped to revive among his countrymen a taste for the noblest studies. His odes, which are full of enthusiasm, are remarkable for hold traits and sublime flights of genius. In his translation of La Fontaine's Fables, he overcame difficulties which were before thought insurmountable, owing to his perfect knowledge of the French and Portuguese languages. Unfortunately, it is not with respect to talent only that he may be compared to other celebrated poets; fame smiled more kindly on him than fortune. The Marquis de Marialva, however, the Portuguese ambassador to the French court, whose kind patronage Manuel had long enjoyed, befriended him in his last illness, and afforded him all the assistance that might be expected from his benevolent disposition and his love of literature and the fine arts. Astronomical Occurrences
In APRIL 1820. The Sun enters Taurus at 45 m. after 4 in the morning of the 20th of this month; and that luminary will rise and set during the same period as in the following
6tb, - - - 34 : - 5 - 36 - - 6
Equation of Time. The following is the difference between apparent and mean time for certain days of this month, and
which must be employed as directed in the table, the difference for the intermediate days being found by proportion.
Phases of the Moon.
Moon's Passage over the first Meridian. The Moon will pass the meridian of the Royal Observatory at the following times, which have been selected on account of their affording favourable opportunities of observing her in that position, if the atmosphere be clear; viz.
April 2d, at 10 m. after 4 in the morning
- - - -
21st, - 29
. 22d, - . 12 - - 8 - - . .
23d, - 52 - - 8 - - - -
. - 10
Phase of Venus. :
Eclipses of Jupiter's Satellites, There are no less than 17 eclipses of Jupiter's first and 8 of his second satellite this month; but none of them will be visible at the Royal Observatory, and therefore their insertion is omitted in this place.
Other Phenomena. Mercury will be in his inferior conjunction at half past 11 at night on the 12th of this month; and Mars will be in quadrature at past 7 in the evening of the 20th. Mercury will also be stationary on the 3d; Georgium Sidus on the 10th; and Mercury again on the 26th. The Moon will be in conjunction with a in Scorpio, at 47 m. past 9 in the morning of the 3d ; with Saturn, at 10 m. after 7 in the evening of the 11th; with Mercury, at 16 m. past 11 in the evening of the 12th ; with B in Taurus, at 23 m. after 2 in the morning of the 17th ; with Pollux, at 49 m. past midnight of the 19th; with « in Leo, at 20 m. after 2 in the afternoon of the 22d; with a in Virgo, at 9 m. past 2 in the morning of the 27th ; and with Antares, at 48 m. after 3 in the afternoon of the 30th. TheMoon will also be in perigee on the 10th, and in apogee on the 22d.
The Moon's Declination Is also given in the ephemeris for every day at apparent noon; but in the Nautical Almanac, it is inserted for both noon and midnight, or for every interval of 12 hours. But both the calculation of the declination itself, and of the correction to be applied to the numbers in the tables to bring them to the time of the Moon's passage over the meridian, when it does not correspond with that for which they are calculated, are much more complicated than those of the Sun's declination. On account both of the variation in the inclination of the lunar orbit, and the irregularities of the Moon's horary motion, it would be foreign to the purpose of the present work
to enter into a full explanation of them. A rule for this latter reduction, illustrated by an example, as applied to the latitude of the Moon, is given in the explanations at the end of the Nautical Almanac; but as the correction arising from the second differences, there explained, often amounts only to seconds, it may frequently be omitted; especially when it is only required to find the Moon's apparent altitude for elevating the transit instrument. In this case, therefore, and which is one that often occurs, the proportion above explained for reducing the Sun's declination to any other time than that for which it is inserted in the tables, may be adopted with sufficient accuracy; and the following example will afford an illustration of the method.
Let it be required to find the Moon's apparent altitude at the Royal Observatory, when she passes the first meridian on the 5th of February 1820.
Now, as this passage takes place at 4 h. in the morning of that day, and the declination, as given in the Nautical Almanac for the preceding midnight, is 8° 14', and for the following noon 11° 1, their difference is 2° 47'; and the time between the former epoch and that for which the declination is required is 4 h.; we therefore have
12:4:: 2° 47' : 55' 40", for the required correction. Hence as the declination is increasing, it being greater at noon than at the preceding midnight, this correction must be added to the go 14, which gives 9o 99 40" for the corrected declination at the time of the passage.
Now it is evident that this proportion supposes the Moon's declination to be increasing uniformly for the 12 hours for which the difference is taken; but by taking the differences in the same manner for the 12 hours both preceding and following this, it will be seen that the rate of increase of the declination was diminishing; for during the former period it was
2° 59', and during the latter, only 20 43'. Hence the above correction was somewhat too great; and 9° 9' may be taken as a near approximation to the true declination at the time of the specified passage. Then, in applying this declination to the problem of finding the altitude,
The complement of latitude = - - • • 38° 31' 20"
29 22 20 Corresponding refraction, add - - ... 1 42 Moon's apparent altitude required ... 29 24 2
The Naturalist's Diary
For APRIL 1820.
SIR JOHN DAVIES. There is something inexpressibly pleasing in the annual renovation of the world, and the new display of the treasures of nature. The cold and darkness of winter, with the naked deformity of every object on which we turn our eyes, makes us rejoice at the succeeding season, as well for what we have escaped, as what we may enjoy; and every budding flower which a warm situation brings early to our view, is considered by us as a messenger to notify the approach of more joyous days.
The SPRING affords to a mind, so free from the disturbances of cares or passions, as to be vacant to