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thus present a singular contrast to each other, inasmuch as the darkness of the night in one is constantly relieved by the presence of our globe reflecting light, while the nocturnal darkness of the other is as constantly left to the illumination of the stars. In another respect also the moon contrasts strikingly with the earth. As she turns upon her axis but once a month, nearly fifteen days' sunlight will alternate with the same period of darkness, and thus the lunar day and night be each of that extent. The physical consequences of this arrangement will be-according to the analogy of terrestrial thingswinter and summer once a month of the fiercest description. During fifteen days' exposure to the sun an intense degree of heat will accumulate, and by fifteen days' deprivation of his beams an equal degree of cold be occasioned; and thus a temperature equal to the most fiery experienced upon the plains of India will alternate with one rivalling in severity that of ice-bound Spitzbergen. But it is a curious speculation, that it lies within the limits of possibility for a lunarian to travel as fast as the moon's motion upon her axis, and thus keep up with the day, living in perpetual sunshine. A ten miles per hour rate of locomotion would suffice for this, and a terrestrial dweller might accomplish that distance by a walk in half the time if transported to the moon, because of the feeble gravitation of bodies at her surface, for a body weighing six pounds at the earth would weigh only one pound at the moon. Consequently the same muscular force would there perform six times as much as on the earth.

Linked in the bonds of a close and enduring relationship to the earth, the surmise is natural, that the two bodies dwelling together in unity harmonise in their physical constitution. We are apt to transfer to the lunar mansion the features of our terrestrial residence—its diversities of ebbing ocean and stable continent—hill, dale, and plain— wood, brook, and flower-stormy wind and balmy breeze. But a course of observation diligently pursued with reference to the satellite corrects some of these imaginings, and discloses striking points of discordance with those of agreement. Whether the lunar globe has any gaseous covering, like that which supplies us with the breath of life, is a subject upon which there has been considerable conflict of opinion. Those who deny the existence of any atmosphere depend chiefly upon the equable brightness of the moon's disk, which, it is argued, would not be the case if she were surrounded with one like ours, so variable in its density, and so often charged with immense masses of cloud and vapour. It is also pleaded, that when the moon occults a planet or fixed star, there is no perceptible diminution of light and alteration of colour before complete obscuration, which there would be, owing to the influence of the lunar atmosphere, if there were one. An occultation of Jupiter took place on the 2d of January 1857, and was carefully observed with this reference. But there was not the slightest distortion of figure, diminution of light, or change of colour. Hevelius, however, and others, have observed variations in the brightness of the lunar orb, instances in which the moon and her spots have not appeared equally lucid and conspicuous, when the terrestrial skies have been free from cloud. Some have also thought that both Jupiter and Saturn undergo a perceptible change of figure when about to be occulted, and that fixed stars may be discovered in such circumstances to experience an evident diminution of light. Professor Nichol observes of the annular eclipse of May, 1836, that just before the rims of the sun and moon osculated, the light of the sun was mollified into lovely twilight, which he attributed to the effect of the moon's atmosphere. One fact is clear, and is admitted by all parties, that if there be a lunar atmosphere, it is of extreme tenuity and exceedingly small, considered by Laplace to be as attenuated as what is called the vacuum of an airpump, and estimated by Schroeter to be little more than a mile in height. Hence, with such a medium, we cannot conceive of some of the grand phenomena with which we are familiar having any existence in the lunar world—such as the noise of many waters and


of mighty thunderings-the voice of the passionate storm, or the melancholy wailing of the autumnal gales. No clouds are there, analogous to those which in ten thousand fantastic shapes are present with us, dropping fatness upon the fields, and casting shadows upon the landscape-a covert in the daytime from the heat. No rain, hail, or snow descends upon the lunar soil. It is difficult to imagine water at all, or any liquid, upon the surface; for if the atmospheric pressure were removed in relation to the earth, its liquids would be dissipated by the heat of the sun; and how much more might this result be expected at the surface of the moon, where the heat accumulated by its fifteen days' continuous exposure to the solar rays must be intense? There can be, therefore, no seas or lakes, or else evaporation would take place, and clouds be formed, perceptible through a telescope. But though apart from the majestic features of the ocean, the tracts of cloud that float in our atmosphere, and the commotions that agitate it, the lunar surface exhibits several points of accordance with the terrestrial superficies. There are mountains answering in their contour to those which diversify our own globe, intermingled with plains, glens, and extensive depressions. To the naked eye, the face of the moon appears chequered, exhibiting dusky patches and bright parts, which, in former times, the fancies of men converted into images of terrestrial things. Thus, Agesianax, as reported by Plutarch, supposed the moon's disk to reflect back to us, as in a mirror, the forms and outlines of our continents, islands, and seas. Nor is the idea so fanciful as not to have occurred to more than one mind. Observers have been impressed with it under widely different circumstances. It has continued to be a popular belief in Western Asia to the present day. Humboldt remarks: "I was once very much astonished to hear a very accomplished Persian of Ispahan, who had certainly never read a Greek book, to whom I was showing, in Paris, the spots on the moon's face through a large telescope, propound the same hypothesis of reflection as that of Agesianax as prevalent in his own country. It is ourselves we see in the moon,' said the Persian; 'that is the map of our earth.'' With the aid of a telescope, the lunar superficies presents an aspect that is excessively torn, ragged, and disturbed; and we are able to define peculiar physical features. There is, however, no foundation for some reports respecting the probable discovery of minute lunar objects; and but little reason to suppose that any instrumental power will be obtained sufficient to disclose them. Schroeter conjectured the existence of a great city on the east side of the orb, north of her equator, an extensive canal in another place, and fields of vegetation in another. Fraunhofer also announced the discovery of an edifice, resembling a fortification, together with several lines of road. The hope has likewise been entertained of discerning the dwellings and persons of the lunarians, should there be any; but these are visions, sanguine and baseless. Assuming, says M. Mädler of Berlin, that a German mile is the utmost limit of distance at which the keenest unassisted eye can distinguish human beings, to bring the moon to that distance, a magnifying power of 51,000 would be necessary; but, up to the present time, 300 is the highest power which has been applied to that object with advantage. Alone therefore, upon this ground, those who indulge the imagination of studying any lunar samples of social and domestic economy, are clinging to a forlorn hope.

The time when the moon's unevenness of surface may be most favourably seen, is when she is horned or gibbous. The boundary of the light and dark parts of the disk would obviously be an unindented line if the disk were perfectly plane, and had no surfaces higher than the rest. But look at the lunar crescent. The bounding line appears notched and broken, which is precisely the aspect which elevations and depressions will produce. Close by the edge of the illuminated portion, yet within the dark part, wholly surrounded with shade, there are small shining points, like islands of light in a sea of darkness. These are gradually joined to the luminous space, and become part and parcel of it, as the moon







In order to understand the phenomena exhibited by the Moon
the most careful and accurate observation of every part or the
lunar disk is required at all the various periods of her libra
tion The position of remarkable spots must be determined
with the most rigourous exactitude as it is found. from
the change or situation relative to surrounding appear
ances consequent upon the Moons phases. that, a spot
dearly distinguishable by the naked eye upon her sur 20
face when at the rull will be with difficulty discerned
even by the glass towards the last quarter.
The appearances observed on the Moon's surface are
caused either by dirierence or level.or by differ
ence or the intensity or the light. The light ref
lected from the surface or the Moon is plainly
seen to be of different shades: although the light
er parts are generally the mountains.& the dark
er ones the low plains. still.caretul observations
have shown that this is not always the case.
but that, the streaks of light which at the full
surpass in brilliancy all the adjacent parts.some
times exist entirely independent or mountains
and extend alike over heights and valleys with
out being affected by them. Besides difference 10
in intensity or the light. colours specifically differ
ent may be observed particularly green sometimes
a colour of a reddish tint at others a yellowish brown
The elevations of the Moon are in general or a much
more precipitous nature than those of the earth. In the
plate the edges of the steeper craters. more especially
those of small extent. are generally shown by a plain line.
the narrow defts or ravines by paralel lines without a cross
tint. The middle edge or the Moon. i.e. the great arce which
in the mean libration seperates the hemisphere which is visible
from that which is invisible is necessarily delineated in profile.
Chains of mountains, or mountainous regions of any importance.are
named arter the mountains of the earth and the various spots after
distinguished men as annexed. To avoid confusing the
objects in the
plate by a profusion or figures. the Moon's surface is divided into four
parts, the numbering or the spots in each commencing with unit.







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Pales Porterdings


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1 Muskelyne
2 Sabine
3 Ritter
4 Godin
5 Rhancus
6 Schubert
7 Apollonius
8 Dionysius
9 dorippa
10 Ariaclaus
11 Triesnedker
12 Firmicus
13 Tarantius
14 Arago
15 Silberschlag
16 Neper
17 Sosigenes
18 Julius Caesar
19 Boscorid
20 Higinus
21 Ukert
22 Azour
23 Condorcet
24 Ross

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25 Hausen

49 Le Monnier
26 Prom Loarwn 50 M.Hadley

27 Puard
28 Jansen
29 Plinius
30 Manilius
31 Alhazen
32 Alhazen S.
33 Produs
34 Macrobius
35 Vitruvius
36 Maraldi
37 Littrow

51 Aratus
52 M Bradleyv
53 Hahn
54 Berosus
55 Tralles
56 Burkhardt
57 Geminus
58 Bernoulli
59 Posidonius
60 Autolyas
61 fristillus
38 Prom Anderusia 62 Gauss
39 Taquet 63 Messala
40 Monclaus 64 Berzelius
41 Bessel
65 Franklin
42 Sulpicus Gallus 66 Calippus
43 Conon.
67 Thevetetus
44 Oriani
68 Cassiu
45 Plutarch 69 Hook
46 Eimmurt 70 Schumacher
47 Cleomales 71 Struve
48 Romer
72 Cepheus


25 Maver
26 Kruft
27 M.Huygens
28 Pythiis
29 Seleucus
30 Lumbert
31 Euler
32 Aristarch
33 Herodot
34 Timodharis
35 Lahire
36 Diophantus
37 Briggs
38 Arimedes
39 Helicon
40 Carlini
41 Delisle
42 Wollaston
43 Lichtenberg
44 Lluch Bewh
45 Lavoisier
46 Piev
47 Prom Laplace
48 Heraclides

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34 Putet

35 Tycho
36 Schilsurd
37 Orentius
38 Sasserides
39 Heinsius
40 Hainzel
41 Drebbel
42 Lehmann
43 Bound
44 Levell
45 Gauricus
46 Wurzelbauer
47 tidus
48 Cupuanus
49 Pazzi
50 Lagrange
51 Walter

82 Guerike
83 Parry

52 Romontanus 84 Bonpland
85 Eududes
86 Letronne
87 Hansteen
88 Herschel
89 Lalande
90 Fra Mauro
91 Flamsteed
92 Damoiseul
93 Grimaldi
94 Mosting
95 Landsberg
96 Lohrmann
97 Ricaoli

57 Campanus
58 Vitello
59 Doppelmayer
60 Fourier
61 Victa
62 Purbach
63 Ries
64 Hippalus
65 Cavendish

73 Versted
74 Mason
75 Plana
76 Burg
77 Eudoxus
78 Mercurus
79 Atlas
80 Hercules
81 Baily

82 Aristoteles
83 Evede
84 Endymion
85 Strabo
86 Thules
87 Gorther
88 Demerit
89 Anhytas
90 Arnold
91 Meton
92 Barrow
93 Euctenon
94 Scoresby
95 Gioja

57 Palitzsch
58 Snellius
59 Petarius
60 Borda
61 Piccolomini
62 Pontanus
63 Werner
64 Apianus
65 Hekataus
66 Biot
67 Santbech
68 Fracastor
69 Polybius
70 Fermat
71 Sacrobosco
72 Azophi
73 Abenezra
74 Playfair
75 La Caille
76 Behaim
77 Vendelinus
78 Cook
79 Colombo

49 Mairun 50 Sharp 51 Louville 52 Harding 53 Gerard 54 Plato 55 Maupertius 56 Condamine 57 Biandini 58 Bouguer 59 Harpalus 60 Venopides 61 Repsold 62 Fontenelle 63 Hornbow 64 Trinaus 65 Geestratus 66 Xenophanes 67 Anaximander 68 Bythagoras 69 Epigenes 70 Anaxavoras 71 Philolaus 72 Anaximenes

66 Byrgius
67 Thebit
68 Arzachel
69 Prom. fenarium
70 Bullwald
71 Agathan hides
72 Gassel
73 Mersentus
74 Alpetoins
75 Alphons
76 Billy
77 Fontana
78 Sirsalis
73 Gruper
80 Ptolemaus
81 Dary

85 Abulfeda
86 Geber
87 Airy

88 Ansgarius
89 Lapeyrouse
90 Macchaens
91 Grillus
92 Theophilus
93 Kant
94 Descartes
95 Dollond
96 Parrot
97 Albatronius
98 Madaurin
99 Langrenus
100 Messier
101 Godenius
102 Guttemberg
103 Capella
104 Isidor
105 Censormus
106 Torricelli
107 Hypatia
108 Alirananus

80 Bohnenberger 109 Taylor

81 Beaumoni
82 Catharina
83 Tacitus
84 Almanon

110 Delambre Ill Theon sen. 112 Hipparchus 113 Reaumur

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