73 



1836. Mr. Chamberlain born. 



1 84 1. Our King born. 



1848. Revolution in France. 



1852. Death of the Duke of Wellington. 



1854. Crimean War. 



1857. Indian Mutiny. 



1859. War between France and Austria. 



1863. Marriage of our King and Queen. 



American Civil War. 



1866. War between Austria and Prussia. 



1870. Franco- Prussian War. 



1873. February — Comet in aphelion, or at greatest 

 distance from sun. 



1879. Zulu War. 



1880. Old Boer War. 



1885. Death of General Gordon. 



1899. Boer War. 



1904. Russo-Japanese War. 



1909. Present time — Comet approaching perihelion. 



Thus a great deal of history has been made while the comet 

 has been completing its present circuit. 



Messrs. Crommelin and Cowell, of the Royal Observatory, 

 Greenwich, have recently made a very laborious investigation into 

 the orbit of Halley's Comet, going far back into the past, as well 

 as looking ahead. In this work they have been assisted by three 

 computers, one of whom. Dr. D. Smart, kindly communicated some 

 valuable particulars to the lecturer. These gentlemen have investi- 

 gated the recorded appearances of the comet in B.C. 12 ; A.D. 451, 

 684, 760, 1066, 1 145, 1222, 1301, 1378, 1456, 1531, 1607, 1682, 1759 

 and 1835. We can only refer to 1066, when it may be called the 

 comet of the Norman Conquest. It is represented in the Bayeux 

 tapestry, and was generally supposed to be a favourable omen for 

 William of Normandy, in his invasion of England, although, as a 

 matter of fact, the comet had come and gone before the battle of 

 Hastings (14th October). 



Messrs. Crommelin and Cowell have also published, many 

 months in advance, an ephemeris giving a series of positions in the 

 sky which will be occupied by the comet at its coming return. 



In view of the fact that the comet has now been "secured," 

 both by the photographic plate and by visual observation, we must 

 alter the anticipatory tone of the lecture (which was delivered long 

 before the comet was seen), and note briefly the facts of its discovery, 

 or re-discovery. A photographic campaign to catch the stranger at 

 the first possible chance was entered upon at Greenwich Observatory 

 on the 9th September last, when two trial exposures on the cal- 

 culated place of the comet were made. These plates were riot 

 closely examined at the time, and meanwhile it was announced from 

 Germany that Professor Wolf had photographed the comet on the 

 night of September nth, two days after the first Greenwich photo- 

 graphs were taken. On re-examining the latter, the comet was 



