It may be taken as a fact (though in no proper sense a rule) that a bright and conspicuous comet comes about once in 10 years, and a very remarkable comet every 30 years. Thus we have had during the present century bright comets in 1811, 1825, 1835, 1843, 1858, 1861, 1874 and 1882, whereof those of 1811, 1843, and 1858 were specially celebrated. Tested then by either standard of words “bright and conspicuous,” or “specially celebrated,” it may be affirmed that a good comet is now due, so let us prepare for it by getting up the subject in advance.
I will not attempt to answer in regular order or in any set form the questions which I have just mentioned as being stock questions, but they will be answered in substance as we go along. There is one matter in connection with comets which has deeply impressed itself upon the public mind, and that is the presence or absence of a “tail.” It is not too much to say that the generality of people regard the tail of a comet as _the_ comet; and that though an object may be a true comet from an astronomer’s point of view, yet if it has no tail its claims go for nought with the mass of mankind. We have here probably a remnant of ancient thought, especially of that line of thought which in bygone times associated Comets universally with the idea that they were especially sent to be portents of national disasters of one kind or another. This is brought out by numberless ancient authors, and by none more forcibly than Shakespeare. Hence we have such passages as the following in _Julius Cæsar_ (Act ii., sc. 2):—
“When beggars die there are no comets seen, The Heavens themselves blaze forth the death of princes.”
In _Henry VI._ (Part I., Act i., sc. 1) we find the well-known passage:—
“Comets importing change of times and states Brandish your crystal tresses in the sky, And with them scourge the bad revolting stars That have consented unto Henry’s death.”
There are in point of fact two distinct ideas evolved here: (1) that comets are prophetic of evil, and (2) stars potential for evil.
There is another passage in _Henry VI_. (Part I., Act iii., sc. 3) even more pronounced:—
“Now shine it like a Comet of revenge, A prophet to the fall of all our foes.”