Climate, portion or zone of the surface of the earth, bound by two circles parallel to the equator, and of such a width that the longest day in the parallel closest to the pole surpasses by a certain quantity, for example by half-hour, the longest day in the parallel closest to the equator. See Earth , Parallel , etc.

Thus "climates" stretch from the equator to the poles, and are like bands or zones parallel to the equator: but strictly speaking there are several "climates" in the width of each zone. A "climate" differs from the closest one only in that the longest summer day is longer or shorter by half-hour in the former than in the latter. Chambers .

The interval of the first "climate" is 8° 30', and of the last one, no more than 3'. To comprehend the reason for this inequality, which comes from a characteristic of the sphere, it is necessary to imagine that in the right sphere, half of the Tropic of Cancer, that is below the horizon, is divided into forty eight equal parts, each of which is of 3° 45', which equals a quarter of an hour. Moreover, that there is such a part to the east and to the west, the closest to the horizon, which both together form a half-hour, which corresponds to the interval of a climate . This being granted, one sees that the reason for the inequality of "climates" comes from the more or less oblique section of the tropic by the horizon, depending on the different elevations of the pole. They cause the horizon to cut the tropic less obliquely at parts equal to 3° 45', taken at eastern and western side, close to the immobile horizon. From this results a bigger difference of the height of the pole than when the tropic is cut more obliquely by the horizon at the same point of 3° 45'. Thus this difference of the heights of the pole, which corresponds to the half-hour of the first "climates," is bigger at the equator than at the polar circles, where the last "climates" are. This makes their interval very unequal and much bigger near the equator than the poles.

Since "climates" begin at the equator, the first "climate" has at its beginning exactly twelve hours of day during its longest day; and at its end, it has twelve hours and a half during its longest day. Mr. Formey.

The second "climate," which begins where the first ends, has twelve hours and a half of day during its longest day; and at its end has thirteen hours of day during its longest day; the same applies to the other hourly "climates," which go to the polar circle. There ends that which Geographers call hourly "climates," and begin monthly "climates." See Hour.

As hourly "climates" are spaces comprised between two circles parallel to the equator, which have their longest day longer by half-hour at their ends than at their beginnings; so monthly " climates" are spaces limited by two circles parallel to the polar circle, situated beyond this circle, and in which the longest day is one month or thirty days longer at its end than at its beginning. See Month. Chambers .

The ancients gave the name "climate" only to areas of the earth that they considered habitable. They assumed that a part of the torrid zone near equator, and a part of the temperate zone above 50° of latitude [north], were uninhabitable; and had only seven "climates." They placed the beginning of the first at 12° 41' of latitude [north], where the longest day of the summer has twelve hours and three quarters, and the end of the seventh "climate" stretched near 50° of latitude [north], where the longest day has 16 hours 20'. To distinguish their "climates" better, the ancients made their middles pass through the most notable places of the old continent; namely, the first through Meroë in Ethiopia, the second through Syene in Egypt, the third through Alexandria also in Egypt, the fourth through the Rhodes Island, the fifth through Rome, the sixth through the Black Sea, and the seventh and last through the mouth of the Borysthenes [Dnieper] River. To those seven "climates," two other have been then added, namely the eighth passing through the Riphaean [Ural] Mountains in Asian Sarmatia and the ninth through Tanais [Azov]. The ancients as the moderns divided the earth into still smaller spaces, called climatic parallels , to distinguish them from other parallels of the equator. Those parallels are just half- "climates," whose space covers only quarter-of-an-hour difference between the longest summer days of each parallel.

The moderns, who traveled much further towards the poles, placed thirty "climates" on each side; and some of them made differences of a quarter of an hour only, instead of a half-hour. M. Formey.

When determining "climates," one usually does not consider refraction. See Refraction.

The name "climate" is commonly given to a land different from another, as regards seasons, qualities of soil, or even people who live there, without any relation to the longest summer days.

Abu-al-Fida', Arab author, distinguished the former type of "climates" by the name "real climates," and the latter by the name of "apparent climates."

One usually reckons twenty-four "climates" of a half-hour and twelve of a half-month. Each of the areas of the latter comprises a fifteen-day difference between the longest summer days . Thus, under the polar circles, the longest summer day is twenty-four hours or one astronomical day; and the longest day under the poles comprises 180 astronomical days, which makes six months. Having established the difference between those "climates" at fifteen days, it is evident that it will take twelve "climates" from the polar circles to the poles; the first of them will begin at the polar circles and the last will end at the poles. And to mark the extent of the twelve "climates," it is necessary to imagine twelve circles parallel to the equator at the beginning and end of each of those intervals. The first [circle] will be the polar circle, where the beginning of the first of those "climates" is; and the last [circle] will be distanced from the pole by 2° 59'. [It] will determine the beginning of the last "climate," of which the pole will be the end. The following tables will acquaint [the reader] with the extent of all the "climates," their degrees of latitude [north], and intervals comprised between them.

Moreover, one should not think that temperature is exactly the same in countries situated under the same "climate" because an infinity of circumstances, such as winds, volcanoes, the proximity to the sea, the position of mountains, combine with the influence of the sun, and often make the temperature very different in two places situated under the same parallel.

The same applies to two "climates" situated in equal distances from the equator, on its two sides; besides, even the warmth of the sun is different in those "climates." They are closer to the sun than we are in their summer, and further away in their winter. See Warmth.

In Book XIV of his excellent work, the illustrious author of the Spirit of the Laws examines the influence of "climate" on mores, character and laws of nations.

After [presentation] of physical details concerning the effects of cold and heat, he begins to explain the contradiction in the character of some nations. Warmth, he says, makes the body weak, on the one hand, and imagination vivid, on the other hand: that is why the Indians are so courageous in some respects, and so weak in others. The weakness of the body makes [them] naturally lazy; hence the attachment of those peoples to their customs; since this weakness makes them avoid even necessary work, wise legislators should, on the contrary, encourage work, instead of promoting indolence, with their laws. It is to the speculative devotion of [the inhabitants of] warm countries that we owe the birth of Dervishism . Habitual drunkenness is a vice of cold countries. Mohammed's law forbidding the Arabs to drink wine conformed in this respect to their customs. Laws [protecting] against illnesses that are not typical to a "climate" but are transplanted there, such as plague, leprosy, smallpox, etc, could not be too severe. Suicide in England is an effect of an illness; and if civil laws in some countries might have reasons to stigmatize suicide, at least in England, one had to regard suicide as an effect of dementia. In the same country, where the common people get so easily tired of life, one feels well that a government of one would have been pernicious, and that laws should govern rather than men. This character of impatience and disquiet is a gage of their liberty. Our ancestors, the ancient Germans, who inhabited cold "climates," had lax laws concerning women's decency. It was different when they saw themselves transported to the warm "climate" of Spain. Among a ferocious nation as the Japanese, laws could not be too harsh, and they are so indeed; it is and it should be different among nations of a gentle character, as the Indians.

Here there is, in a few words, what the author says about the effects of "climate," and with which some writers have reproached him, as if he made everything depend on "climate." Whereas, on the contrary, his work is meant to expose an almost infinite multitude of causes, which influence laws and characters of peoples, and among which, one cannot deny, "climate" is one of the principal. This is the idea one should have of what one reads on the subject in the book, into which might have slipped some propositions that require to be clarified, but in which one sees a profound philosopher, virtuous citizen shine. Our nation gave it the applause it deserved, and foreigners regard it as a work that brings honor to France.