L M L M L M L M 1790 1798 1807 1816 1826 1835 1844 1853 1791 1799 1808 1817 1827 1836 1845 1854 1792 1800 1809 1818 1828 1837 1846 1855 1793 1801 1810 1819 1829 1838 1847 1856 1794 1802 1811 1820 1830 1839 1848 1857 1795 1803 1812 1821 1831 1840 1849 1858 1796 1804 1813 1822 1832 1841 1850 1859 1797 1805 1814 1823 1833 1842 1851 1860 1806 1815 1824 1834 1843 1852 1861 1825 When the moon is viewed through a good telescope, there appear vast cavities and asperities on various parts of her face, some of them extremely resembling deep caverns and vallies, and others mountains. “Turn’d to the sun direct, her spotted disk Shows mountains rise, umbrageous vales descend, And caverns deep, as optic tube descries.” The cavities, it is conjectured, do not contain water; hence it is concluded that there can be no extensive seas and oceans, like those which cover a great part of our earth. It is, however, imagined that there may be springs and RIVERS. The moon seems, as a learned author has observed, in almost every respect to be a body similar to our earth, to have its surface diversified by hill and dale, mountains and vallies, rivers and lakes. With regard to a lunar atmosphere, the existence of which has long been a subject of much dispute, it is now generally admitted.[122] The irregularity of the moon’s surface, arising from hills and vallies, renders her more capable of reflecting the sun’s rays to us. Though philosophers have differed widely in their ideas concerning the materials of the moon’s mountains, some from their brilliancy even supposing them to be rocks of diamonds, there is no diversity of opinion as to their use. If smooth and polished, like a mirror, or covered with water, she would not reflect and distribute the light received from the sun. In some positions she would show us his image no larger than a single point, and with a lustre that would injure our sight: but roughened by these hills and vallies, her surface returns the sun’s light to us in an equable and pleasant manner, and enables us to examine her with ease and precision.