270 THE WORLD MACHINE 



Shortly after his assassination a flaming apparition visited the 

 sky, a vast and graceful trail of light. It shone so brilliantly 

 that it could be seen for several hours before sunset. It held 

 its portentous way in the heavens for eight days, then dis- 

 appeared. Small wonder that the Romans should have given 

 to this effulgence the name of the Julian Star, and regarded it 

 as a celestial chariot sent to convey the soul of Caesar to the 

 skies. 



These apparitions were not uncommon ; the terror they 

 inspired was sometimes beyond measure. In the year 1456 

 came one of unwonted splendour. Constantinople had just 

 fallen before the invading arms of the Saracen. " The appari- 

 tion," says Draper, " was considered a harbinger of the vengeance 

 of God, the dispenser of the most dreadful of his retributions, 

 pestilence, famine, and war." By order of the Pope, all the 

 church bells of Europe were rung to scare it away ; the faithful 

 were commanded to add each day another prayer. As they 

 said their Ave Maria, they joined to their supplications to the 

 Holy Mother the words : " Lord save us from the devil, the 

 Turk, and the comet." 



In the year 1910 one of these flaming messengers will appear 

 in the sky ; the time of its coming will be calculated perhaps 

 to a day. The faithful will not fall upon their knees ; no new 

 prayers will be said ; the church bells of Europe will not ring. 

 It will not be regarded as a portent of famine or war ; if the 

 greatest of living statesmen dies upon its approach, it will not 

 be thought of as a special vehicle to waft heavenward his soul. 

 What has wrought the change ? 



The answer may be a little technical, but we may say with 

 some approach to accuracy, Newton and his law of attraction. 

 Up to Newton's time the comet was still a mystery. Its appear- 

 ance inspired an instinctive dread in even the stoutest hearts. 

 In the year 1680 came a wonderful specimen. Newton watched 

 it rush downwards towards the sun, spin round about it in an 

 abrupt turn, then rush away again and disappear from sight. 

 He did not tremble ; he observed. Then he calculated. Newton, 

 despite his theologising predilections, had a very concrete and 

 material sort of mind ; he reflected that if this apparition were 

 of a material nature it must be subject to the influence of gravita- 

 tion and obey the formula whose secret he had seized. It would 

 then move in one'or other of the conic sections, as do all projec- 



