1 8 Projessor Turner on 



the dread of comets, which were believed to threaten if not the 

 very existence of the world at any rate pestilence or death. The 

 lecturer illustrated this feeling by quotations from Milton's 

 " Paradise Lost " and the diary of John Evelyn. A comet observed 

 in 1590 was supposed to be responsible for the sneezing plague, 

 which brought into use the familiar expression "God bless you" 

 when a person sneezed, those words being a prayer that the 

 individual affected might not be stricken. Familiarity and 

 knowledge had done away with the fears to which he had referred. 

 Comets had become much more familiar since the invention of 

 the telescope, but it was interesting to note that photography had 

 not the same effect on comets as on planets. The best time to 

 see a comet was when it was near the sun, and then of course it 

 could not be photographed, because the light would fog the plate. 

 Comet-seeking involved great assiduity and labour, some discoveries 

 being made by diligence and others by accident. They moved 

 in curves called conic sections, either a parabola or an ellipse. 

 In the discovery of the law of gravitation Newton laid the basis 

 of all their knowledge of the movements of comets and planets. 

 Continuing, Professor Turner described Halley's work at Oxford, 

 and how he discovered that the comet called after him came back 

 every seventy-five or seventy-six years. Halley knew he could not 

 live until its return, and he expressed in writing the hope that 

 when it did come back, as it did in 1758, posterity would 

 remember that the prediction was first made by an Englishman. 

 The comet had been traced back to 240 B.C., and as a matter of 

 fact it appeared at the Norman Conques:, at the Reformation, 

 when the first American colony was founded, and when Nelson 

 was born. There was also a political significance attached to its 

 appearance, for it was a curious thing that the results of the 

 elections of 1835 and 1910 were almost exactly the same. The 

 comet had gone now, and if an , election took place he did not 

 know what would happen. A comet was not heavy. It was 

 possible that the whole mass of the comet was no bigger than that 



