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cated a single leisure hour to sober conversation or innocent pleasantry, to any of the endearing intercourses of domestic or social life, or to any rational purpose whatever. He is generally acknowledged to have spent all the time in which he did not paint, in drinking, and in the meanest dissipations, with persons the most eminent he could select for ignorance or brutality; and a rabble of carters, hostiers, butchers' men, smugglers, poachers, and postilions, were constantly in his company, and frequently in his pay. He was found at one time, we are told, in a lodging at Somers-town, in the following most extraordinary circumstances: his infant child, that had been dead nearly three weeks, lay in its coffin in one corner of the room; an ass and foal stood munching barley-straw out of the cradle; a sow and pigs were solacing in the recess of an old cupboard; and himself whistling over a beautiful picture that he was finishing at his easel, with a bottle of gin hung up on one side, and a live mouse sitting (or rather kicking) for his portrait, on the other!

Astronomical Occurrences

In OCTOBER 1819.

The Sun enters Scorpio at 9m. after 6 in the morning of the 24th of this month; and he rises and sets during the same period at the times specified in the following

TABLE Of the Sun's Rising and Setting for every fifth Day. October 1st, Sun rises 11 m. after 6. Sets 49 m. after 5

6th,
11th,
16th,

19
21st,
26th,
31st,

11

- 22
- 32
41

38 28

5
5

51

6 6 6 6 7 7

1

9 59 49

57

3

Equation of Time. If the following numbers be subtracted from the time as indicated by a good sun-dial, the remainders will be the time which should be shown by a well regulated clock at the same instant.

TABLE. Friday, October 1st, from the time by the dial subtract 107 Wednesday, 6th,

11 40 Monday, 11th,

13 3 Saturday, 16th,

14 13 Thursday, 21st,

15 10 Tuesday, 26th,

16 0
Sunday,
31st,

16 12
Phases of the Moon.
Full Moon, 3d day, 22 m. after 3 afternoon.
Last Quarter, 11th

2 morning
New Moon, 19th 55
First Quarter, 26th 54

5 Moon's Passage over the Meridian. The Moon will pass the first meridian of this country at the following convenient times for observation, if the weather prove favourable: yiz.

October 1st, 89 m. after 10 in the evening.
10th, 29

5 morning.
11th, 21

6
12th, 10

7
25th, 54 - - 5 in the evening.
26th, 52
27th, 47

7
28th, 38
29th, 26
Soth, 14

10 The Moon will also be eclipsed on the 3d of this month. But as the eclipse begins about 36 m. after 1 in the afternoon, and she does not pass the meridian of the Royal Observatory till past 12 at night, the eclipse will necessarily be invisible in this country, as the Moon will not have risen at the time.

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Phase of Venus.

11.99159 digits. Oct. 1st Enlightened part:

0.00841 Venus is at this time evidently very near her superior conjunction, since nearly the whole of her disc would be seen enlightened, if not for the rays of the Sun, which prevent her from being visible at this time. Her conjunction, indeed, takes place at 30 m. after 6 in the evening of the 9th.

Eclipses of Jupiter's Satellites. The following will be the eclipses of Jupiter's Satellites visible at the Royal Observatory this month.

EMERSIONS.

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1st Satellite 4th day, at 40 m. after 9 evening.
21st

1

8
2d Satellite 6th 21

8
Form of Saturn's Ring.
October 1st {Transverse ditto
Conjugate diameter

054 Other Phenomena. Mercury will be in superior conjunction at 15 m. after 8 in the morning of the 21st. Venus at 30 m. after 6 in the evening of the 9th. Mars will be in quadrature at 30 m. after 12 on the 15th. Jupiter will be stationary on the 4th. The Moon will be in conjunction with Saturn at 59 m. after 5 in the evening of the 2d; with B in Taurus at 2 m. after 11 in the night of the 8th; with Pollux, at 32 m. past 10 in the morning of the 11th; with Spica in Virgo, at 14 m. after 9 in the evening of the 18th; and with a in Scorpio at 19 m. past 9 in the morning of the 22d of this month. On the EFFECTS of GRAVITATION.

(Continued from p. 234.) The effects of gravity are familiar to us in the oscil., lations of the pendulum, from which society receives

so much advantage as a measure of time. The same instrument has also been applied with great success in determining the figure of the Earth. The length of the pendulum, which is the distance between the centre of suspension and the centre of oscillation of the vibrating body, is always in proportion to the force of gravity at the place where it is used, when the time of vibration is constant; and hence the pendulum becomes a proper instrument for measuring its intensity; and, consequently, for ascertaining the comparative distances of different places from the centre of attraction. If we denote the length of the pendulum by l; the intensity of gravity, as measured by the space which a heavy body would describe in a second with the velocity acquired in the first second of its descent uniformly continued, by g; the ratio of the diameter of a circle to its circumference by m; and the time of one vibration by t; then mathematicians prove that, when the arcs of vibration are small, the relation between the length of the pendulum and the time of its vibration is expressed by the equation,

tTV

g In any other situation, where the length of the pendulum is t, and the intensity of gravity g', the same relation is expressed by

T t =

ova

Now if the times in both instances be equal, as one second, for example, we necessarily have

//=/

TV

9 but as 7 iş common to both sides of the equation, we may divide by it, and then

I' 7

V /=/

By squaring both sides, we have

1 ľ

i

g g' and by converting this equation into a proportion,

ļ : 1 :: 5 : g'. When, therefore, the length of the seconds pendulum is found by experiment in different parts of the globe, the ratio of the intensity of gravity in these places is determined.

As the pendulum is caused to vibrate by the force of gravity, the greater the intensity of this force, the greater will be its velocity, and, consequently, the quicker its vibrations, when the length of the pendulum remains constant. The duration of each of these oscillations is ascertained by the number which a pendulum makes in a given interval between two consecutive passages of a star over the same meridian; for instance, when a pendulum is transported to different parts of the earth, experience shows that the velocity of its oscillations increases from the equator to the poles; and the law of this acceleration, which has been determined with great accuracy, is as the square of the sine of the latitude; as the rotation of the globe on its axis requires, Richer, who was sent by the French Academy of Sciences to Cayenne, for the purpose of making astronomical observations, was the first who put this interesting fact to an experimental proof. He found that his clock, which had been regulated to mean time at Paris, lost a sensible quantity every day at Cayenne. This was the first direct proof that was obtained of the diminution of gravity at the equator; and it has since been very carefully repeated in a great number of places, all of which have confirmed the general result; the resistance of the air being also taken into consideration. The following table shows the general results that have been obtained on this subject; the length

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