tail spread perpendicularly over the sky, the weather being very hot. Every one now believes in war."[1]
Of the influences ascribed to comets in the popular mind one which has survived quite to the present day is that comets cause an abnormal developement of heat on the Earth. When there has happened to be visible a comet of sufficient importance or brilliancy to get into the newspapers, and the season of the year has been the summer, or early autumn, and the weather has been very sunny and hot, I have often been asked in solemn tones (especially by ladies) whether the comet was the cause of the heat; the question being put in the form called by a lawyer a "leading question", one to which an affirmative answer is expected.
Lord Malmesbury, in the work just quoted, alludes casually to this popular idea. Under the date of 1857, June 25, he says:—"We are suffering under an extraordinary heat. People are really getting alarmed, for if it is occasioned by the comet, which is not yet visible, what must we expect when it reaches our Globe!" It does not appear what comet is here referred to, but presumably it is that of 1556, whose return was expected somewhere about 1858 or 1860.[2]
The French astronomer Arago, more than 70 years ago, complained that questions of the same type were raised in France, and he wrote a somewhat satirical article dealing with the subject,[3] in which he alluded to the scarcity of the meanest knowledge of scientific facts amongst the middle ranks of society. He condescended, however, to gather up some statistical facts by way of showing the futility of the suggestion. His labours were taken advantage of in England in an article attributed to the late Professor De Morgan. [4] Allusion is made therein to the supposition that the successful vintage of 1811 was due, as already mentioned, to the great Comet of 1811; and that the excessive heat of August and
