238 POPULAR SCIENCE MONTHLY. 



Christian times the great festival of rejoicing for the men of the 

 north temperate region. Day by day they saw the sun recede and 

 the cold deepen; at last, one evening, he sets a little nearer, and 

 they know that he has not deserted them forever. Similarly, the 

 promise made at Yule begins to be realized at that other great feast 

 of the spring equinox, which we still call in England by its ancient 

 heathen title of Easter; the day by that time has got the better of 

 the night, and " the sun dances on Easter Sunday " in commemora- 

 tion of his completed victory over the combined powers of winter 

 and darkness. In the tropics, on the other hand, the connection 

 is less clear; but even here the shifting of the sun's apparent place is 

 closely correlated with the shifting of the rain zone; and therefore 

 it would not be long (after man was man) before tropical savages 

 began to perceive a constant relation between the movements of the 

 sun to north or south, and the occurrence of the fertilizing rainy 

 season. "We must remember that savages, with their improvident 

 habits, are much more dependent upon rain than we are, and that 

 magical ceremonies for breaking up a drought are among their com- 

 monest and most universally diffused superstitions. 



On the whole, then, before the coming on of the Glacial epoch, 

 we may be pretty sure that plants and animals on the one hand had 

 learned organically and automatically to recognize the existence of 

 the year and to adapt themselves to it; and that men or the pro- 

 genitors of men on the other hand had also learned to correlate the 

 recurrent seasons of food supply with the movements of the sun, 

 though nothing equivalent to winter and summer as we know them 

 to-day existed as yet on any part of our planet. I say advisedly " on 

 any part of our planet," because even near the pole itself remains 

 of a subtropical vegetation in Tertiary times have been amply indi- 

 cated. Nevertheless, in all parts of the world then, as in the tropics 

 now, we may gather that plants and animals ran through annual 

 cycles — that the year, as I have put it, was organically recognized. 

 Trees had their time to sprout, to bud, to flower, to fruit, to seed, 

 to shed their leaves (in the evergreen way) ; birds had their time to 

 nest and hatch out their young; insects had their fixed periods for 

 laying, for larval life, for assuming the chrysalis form, for becoming 

 winged beetles or bees or butterflies. In one word, the year is a ter- 

 restrial reality, not merely an astronomical fact, in the tropics now; 

 it was a terrestrial reality over the whole planet in the Tertiary 

 period. But it was hardly more marked, apparently, into distinct 

 seasons than it is marked to-day in the equatorial region. Kainfall 

 and drought must have had more to do in determining the annual 

 cycles than winter and summer. 



Erom all this it must result that the conception of the year as 



