THE RETURN OF HALLEYS ComMET IN 1910. 19 
in many respects very mysterious ; to the ancients the mysteries 
that they presented were quite baffling, and seemed to traverse 
all that they knew, or thought they knew, about the heavenly 
movements, which they rightly regarded as the embodiment. of 
majestic law and order, “ Let them be for signs and for seasons 
and for days and years”; “He hath established them for ever 
and for ages of ages; He hath made a decree, and it shall 
not pass away.” We may not all of us realise how fully these 
movements were understood even 2,000 years ago; thus Fathers 
Epping and Strassmaier published a work a few years ago on 
the Babylonian astronomy as revealed by the cuneiform tablets, 
in which they showed that a regular astronomical almanac like 
our Nautical Almanac was published year by year, predicting 
the places of the sun, moon, and planets for the year. (Father 
Kugler is now bringing out a still fuller treatise on the same 
subject.) When they came to the comets, however, their power 
of prediction utterly broke down. These were utterly unlike 
the other bodies in their appearance and their movements, 
which refused to conform to the Zodiac or track of the planets, 
but were at random in all directions, and in all parts of the 
heavens. They were often so extremely rapid as to suggest 
great proximity, possibly even within the confines of our own 
atmosphere, in which case the apprehension was quite natural 
that evil effects, such as pestilence and famine, might be the 
result of their approach. It was indeed almost impossible for 
the ancients to form a true idea of the cometary movements ; 
their mathematical knowledge was not sufficient. Seneca, an 
illustrious Roman philosopher, who lived at the beginning of 
the Christian era, made a remarkable prediction about comets. 
“Some day there will arise a man who will demonstrate in 
what regions of the heavens the comets take their way; why 
they journey so far apart from the other planets ; what their 
size, their nature” (Quest: Nat., lib. vii, ce: xxvi). For over 
1,600 years this remarkable prophecy remained a dead letter ; 
then at last the man appeared, of whom it is said :— 
Nature and Nature’s laws lay hid in night, 
God said ‘ Let Newton be,” and all was light. 
Newton showed that, under the force of gravitation attracting 
according to the law of the inverse square of the distance, four 
forms of orbit were possible; first, the circle, which is very 
nearly the course pursued by the earth and most of the planets. 
Secondly, the ellipse, or oval, which shades through all varieties 
of flattening from an almost circular form, as in the orbits of 
