EECEEATIYE SCIENCE. 



249 



No. 



104 



105 

 106 

 107 

 108 

 109 

 110 



in 



(100) 

 112 

 113 

 111 

 115 

 116 

 (56) 

 117 

 118 

 119 

 (100) 

 (87) 

 120 

 121 

 123 

 123 

 124 

 125 

 123 

 127 

 128 

 129 

 130 

 131 

 (87) 

 132 

 133 

 (100) 

 134 

 135 

 130 



Year, 



1788 ii, 

 1790 i, 



1792 1. 



— ii. 



1793 i 



— ii. 

 1795 

 1796 

 1797 



1798 i. 



— ii. 



1799 i. 



— ii. 

 1801 

 1802 

 1804 

 1805 

 1806 i. 



— ii. 

 1807 

 1808 i. 



— ii. 

 1810 

 1811 i. 



— ii. 

 1812 

 1813 i. 



— ii. 

 1815 

 1816 



1818 i. 



— ii, 



— iii 



1819 i. 



— ii. 



— iii. 



— iv. 



PP. 



d.h. 

 Nov. 20, 7 

 Jan. 15, 5 

 Jan. 2S, 7 

 May 21, 5 

 Jan. 13,13 

 Dec. 27, 6 

 Nov. 4, 20 

 Nov. 28, 5 

 Deo. 21, 10 

 April 2, 19 

 July 9, 2 

 AprU 4, 11 

 Dec. 31,13 

 Sept. 7, 5 

 Dec. 25, 21 

 Aug. 8, 13 

 Sept, 9, 21 

 Feb. 13, 15 

 Nov. 21, 12 

 Jan. 1, 23 

 Dec. 28, 22 

 Sept. 18, 17 

 May 12, 22 

 July 12, 4 

 Oct. 5, 19 

 Sept. 12, 

 Nov. 10, 23 

 Sept. 15, 7 

 Mar. 4, 12 

 May 19, 10 

 April 25, 23 

 May 1, 8 

 Feb. 7, 9 

 Feb. 25, 23 

 Dec. 4, 22 

 Jan. 27, 6 

 June 27, 17 

 July 18, 21 

 Nov. 20, 5 



n. 



7573 

 7581 

 0632 

 ■7979 

 ■2930 

 9662 

 ■4034 

 ■4951 

 ■3344 

 ■5781 

 ■5266 

 ■484 

 ■7795 

 8399 

 6258 

 •2617 

 0941 

 0772 

 3404 

 9068 

 0815 

 ■6461 

 3898 

 6079 

 9691 

 0351 

 5821 

 7771 

 6991 

 2161 

 2128 

 0485 

 7332 

 1977 

 8550 

 3352 

 3410 

 7736 

 8925 



0-97342 



0-84888 



0-81617 

 0-74578 



0*99548 



0-99509 

 0-98271 

 095454 



0-93121 



0-81858 



0-75519 

 0-68674 



Discoverer. 



Miss Hcrsehel 



Diito 



Moehain 



Miss Herschel 



Ditto 



Gregory 



Messier 



Perny 



Miss Herschel 



Olbera 



Bouvard 



Messier 



Bouvard 



M(5chain 



Ditto 



Beissig 



Pons 



Ditto 



Thulis 



Pons 



Ditto 



Parisi 



Pons 



Ditto 



Ditto 



Flaugergues 



Pons 



Ditto 



Ditto 



Ditto 



Olbers 



Pons 



Ditto 



Ditto 



Ditto 



Ditto 



Tralles 



Pons 



Blanpaia 



Duration 

 of Visibility. 



4 weeks. 



2 weeks.*' 



3 weeks. 

 10 weeks.** 



6 weeks. 

 6 weeks.*' 



15 weeks. 

 10 weeks.'* 



3 weeks.'' 



2 weeks. '2 



3 weeka.'-J 

 6 weeks. 



1 week.'-* 

 3 weeks.'' 

 10 .days.'* 

 3 weeks." 

 6 weeks.'* 

 3 weeks." 



3 weeks. 8* 



4 weeks.*! 

 14 weeks. 

 28 weeks S2 



1 week '3 

 10 days.8* 

 6 wei-ks. 



17 months." 

 13 weeks. 8* 



10 weeks."' 



5 weeks. 



6 weeks." 

 25 weeks."'' 



11 days.s"> 



4 days." I 



18 weeks. 



9 weeks.s* 



7 weeks. M 



16 weeks." 



5 weeks.** 



8 weeks.** 



*' Imperfectly observed on four occasions. Elements 

 but approximate. 



*' Visible to the naked eye, with a tail 4" long. 



*' Discovered by M^chain and Piazzi, January 10. There 

 was a trace of a tail to be seen. 



'* Discovered by Miss Herschel, October 7. An elliptic 

 orbit. Period assigned, 422 years. 



'1 An apparition of Encke' s comet. It was just visible to 

 the naked eye. 



'2 Very faint. 



'■> Discovered Viy Miss Herschel, and Lee on the same 

 evenin<r; by Kudiger, August 15, andbyKecht, August 16. 



'■• Discovered by Olbers, December 28, Elements only 

 approximate, 



'5 Discovered by Olbers, August 26. At first faint, but 

 afterwards visible to the naked eye, with a tail 1° long;. 



'* Probably a return of the comet of 1699. Visible to 

 the naked eye, with a tail from 1° to 3='. 



"'Discovered at Paris, July 12, The observations were 

 very rough. 



'* D.scovered by M^chain, August 28, and by Olbers, 

 Sei)tember 2. 



'9 Discovered by Bouvard, May 10, and by Olbers, 

 May 12. 



*"• A\i apparition of Encke't comet. Discovered by Pons 

 and Bouvard, October 20, and by Huth some days after- 

 wards. Visible to the naked eye, with a tail 3^ long. 



*i An apparition of Biela's comet. Discovered by Bou- 

 vard, November 16, and by Huth, November 22. Visible to 

 the naked eye. 



*•* Discovered by Pons, September 20, It was visible 

 to the naked eye, with a tail 5° long, an elliptic orbit. 



Period assigned, 1714 years, which may, however, be exr 

 tended to 2157 years, or reduced to 1404 years, 



*•* Discovered by Wisniewski, March 29. 



*• Elements only approximate. 



** A very celebrated comet, conspicuously visible in the 

 autumnal evenings of 1811. It had a tail 25" long, and 6'' 

 broad. The most reliable computations assign a periodic 

 term of 3065 years, subject to an uncertainty of not more 

 than 43 years. The orbit of this comet is liable to much 

 planetary perturbation. 



** An elliptic orbit. Period assigned, 875 years. Visible 

 to the naked eye. 



*' An elliptic orbit. Period assigned, 70-68 years. Visible 

 to the naked eye, with a tail 2^ long. 



*" Discovered also by Harding. Visible to the naked eye. 



** An elliptic orbit. Period assigned, 70-049 years. 

 Bessel anticipates that planetary perturbation will bring 

 it back to perihelion, 1887, February 9, It had a short 

 tail. 



** Elements only approximate. 



*i An apparition of Biela's comet. The observations 

 were few and indifi'erent. 



*^ Discovered by Bessel, December 23. It moved very 

 rapidly. Eosenberger has computed a hyperbolic orbit. 



"^ An apparition of Encke't comet, whose periodicity 

 was now discovered. 



** A very brilliant comet, with a tail 7" long, 



** An elliptic orbit. Period assigned 5-618 years. Con- 

 sidered by Clausen as a return of the comet of 1766 (ii). 



** Discovered by Pons, Dec. 4. An elliptic orbit ; period 

 assigned, 4-810 years. Clausen thought this comet might be 

 identical with that of 1743 (i). 



{To he continued.) 



Geo, F. Chambees. 



Y 



