252 



AUTUMN. 



Niger ; sometimes it is between the mountains and 

 the plain ; at other times between the land and the 

 sea ; and the periods vary so much, that in some in- 

 stances, while the one side of an island, or narrow 

 piece ofland, has rain in abundance, the other side is 

 parched up with drought. In one place, the alterna- 

 tion takes place only once in the year, while at 

 others it takes place twice, and there is a double sea- 

 son of fertility ; and in some favoured spots, where 

 the currents meet laterally, there are showers all the 

 year round, and perpetual growth and fertility. No 

 general theory of the tropical seasons can thus be 

 established, cither as to time of occurrence or dura- 

 tion, and so they must be made the subject of local 

 observation for every place. But still, even in the 

 wild and uncultivated places, there is an autumnal 

 pause when the season of growth is over. Very 

 many of the herbaceous plants which die down have 

 tuberous or farinaceous roots, into which the sub- 

 stance of the plant is there concentrated, and the 

 rude people dig these up, and roast them as substi- 

 tutes for bread ; while those which are more advanced 

 and thickly peopled, and most cultivated, are, at a dis- 

 tance from river courses, obliged to da it at vast la- 

 bour from tanks of water collected in the wet season, 

 or from wells, which have sometimes to be dug to the 

 depth of 300 or 400 feet ; so that, if they are ex- 

 empted from the labour of building close houses, pre- 

 paring warm clothing, and keeping constant fires, 

 they have not their sunny skies for nothing, but must 

 toil as hard as they of temperate climes. 



In these places, many of the smaller animals dis- 

 appear in the seasons of drought ; some by perishing 

 and leaving only the eggs to produce a new race, as 

 is the case of many tribes with us during the winter ; 

 others get into the ground or otherwise hide them- 

 selves, and hybcrnate or perhaps cestivate ; for, in 

 our sense of the words, the dry season may be called 

 either winter or summer, as it has the sterility of the 

 one and the heat of the other. The larger animals 

 also prepare for the season, but it is by casting part 

 of their covering, and not getting an addition to it as 

 exposed animals do with us against the winter. Many 

 of the birds too, migrate, and they do so because the 

 parched countries cease to yield them food. But 

 though in those tropical regions, there is plenty of 

 change, there is no autumnal action and no autumn. 

 As little is there any spring ; for by the time that 

 the violence of the opening storm is so far over that 

 men can come out of their houses and hiding places 

 and survey the fields, the world is absolutely new. 

 The fields which when last seen were dry and barren 

 as a rock, are green with leaves and gay with flowers, 

 as if Eden had been charmed forth from the wilderness, 

 instantaneously and by magic. Sometimes they ap- 

 pear new to a greater extent, for the first floods are 

 often so violent that they uproot trees, tear up the 

 earth, and scatter fragments of rocks and banks of 

 rubbish, till the general features of the country are 

 entirely changed ; yet these rocks and that rubbish 

 remain but brief space before they too are vested 

 and shrouded in the luxuriance of the new vege- 

 tation. 



Such is the one extreme of season, that in which 

 summer, varied only by drought and humidity, may 

 be said to hold unbroken sway all the year round. 



Let us now take a hasty glance at the other ex- 

 treme, that in which winter and summer may be said to 

 divide the year ; and where that which might be called 



autumn or spring, has no fixed character as a sepa- 

 rate season, Imt is a sort of conflict between these 

 two. The knowledge of this extreme is as necessary 

 as that of the other, before we can have correct no- 

 tions of the character and value of autumn in the 

 temperate climates ; and, indeed, we can understand 

 nothing in nature rightly, if we do not take it in con- 

 nexion with its class. 



The common notion is, that the cold increases 

 with the latitude, till we reach the pole of the earth's 

 rotation, and that there it is a maximum, the capital 

 and throne of winter as it were ; and that this would 

 .be the case upon mechanical principles is unquestion- 

 ably true, because it accords with the ratios in which 

 the sun's light falls upon the earth, supposing the 

 surface uniform. And up to a certain point we can 

 trace a near approximation, if not a perfect accord- 

 ance to the mechanical law ; or if there arc local 

 deviations, we can trace them to local causes. But 

 a mechanical theory, though the splendour of New- 

 ton's discovery long made it be regarded as a univer- 

 sal instrument of science, and many still look upon it 

 as such, is not a complete, or altogether a safe guide, 

 in matters of natural history ; and there is thus much 

 in it of rather a provoking character, that it applies 

 best in those parts of the inquiry where we could do 

 best without it, and fails where we need it as our 

 only guide. In a great measure, at least, it is so 

 with the increase of cold toward the poles, or the 

 seat of its greatest intensity. The accounts of the 

 recent voyagers by sea and travellers by land in 

 quest of a north-west passage (or any thing else they 

 could find) on the north ot the American continent, 

 cannot be received as demonstration, though they 

 must be admitted as truths so far as they go. Now 

 the inference from them is, that on the north of Ame- 

 rica, the maximum of cold is about the latitude of the 

 magnetic pole, or about 71. The trend of the ice 

 in the North Sea, and observations that have been 

 made at many points of the circumference, shows that, 

 in these high latitudes, the isothermal lines, or lines 

 of the same temperature, do not lie on parallels of 

 latitude, or nearly so, even supposing that allowance 

 is made for differences of surface and elevation. 

 Thus we can no more find, in the regions of the 

 poles, a definite parallel of latitude at which to fix 

 the maximum of average cold for the year, than we 

 can find one in the regions of the equator from which 

 to date the maximum of average heat : we find the 

 same temperature more southerly-in one latitude, and 

 more northerly in another ; and whenever we find 

 the cold far to the south, spring and autumn are 

 always less marked ; and they are always more so, 

 and even a greater range in latitude, as the cold is 

 further to the north. Thus if we take the latitude in 

 North America, which corresponds to that of the 

 coast of the Channel in England, we find that in 

 America there is hardly any spring or autumn, and 

 that on the coast of the Channel, except in blcatf 

 situations, there is little, if any thing, which an inha- 

 bitant of Canada, even considerably to the south of 

 the parallel of the Channel, would call winter. 



In the very extreme of the cold, whether situated 

 more or less to the north, there is very little in which 

 autumnal appearances can display themselves. The 

 presence of snow and ice covering the land and con- 

 cealing the sea, and their partial or total absence, are 

 he first markings of the arctic seasons ; and it is not 

 i settled point whether the absence of any thing 



