El Jem was situated in a province which in Roman times was called Frugifera, the fruit-bearing province. Today it is almost completely deserted, with a few Arab huts scattered about at the foot of the great buildings. This same picture occurs again and again. Homer speaks about the tall oaks and pines of Sicily. Now you can cross Sicily from one side to the other and hardly see a single tree. There are a few places where attempts at reforestation have been made, but this once extremely well-forested, well-wooded country is now almost completely naked. The same is true of Greece, of Palestine and Syria, of Spain, and of Southern Italy.
Now we have to pass to another area of destruction at least as important as the destruction of forests—and resulting in some measure from it: the destruction of the soil.
The soil is a living organism. It owes its fertility to the existence within itself of great numbers of ecological communities of microscopic and macroscopic organisms of every kind. The topsoil, however, which contains almost all the soil’s fertility, is not deep. The 2.8 billion people who are now inhabitants of the planet depend upon a layer of soil rarely more than about ten inches thick—and it takes three hundred to one thousand years to create an inch of it, so one sees the extreme danger of any process causing soil destruction.
Soil erosion, of course, happens all the time; it is one of the regular processes of geological change. But there is an immense difference between the slow erosion of nature left to itself and the rapid and destructive erosion which takes place when man wantonly strips the land of its vegetable cover, cuts down the forests, tears up the grass, or uses bad agricultural methods which leave the land vulnerable to the wind and the rain. Unfortunately, as we have seen, man has been committing such crimes against nature for a very long time.
One of the best descriptions of erosion was written, curiously enough, by Plato in his dialogue, the Critias, where he speaks of his own native country of Attica. It is worth reading because it is remarkable how accurate the description is. He says:
In comparison of what then was, there are remaining only the bones of the wasted body, as they may be called, as in the case of small islands, all the richer and softer parts of the soil having fallen away, and the mere skeleton of the land being left. But in the primitive state of the country, its mountains were high hills covered with soil, and the plains, as they were termed by us, of Phelleus, were full of rich earth, and there was abundance of wood in the mountains. Of this last the traces still remain, for although some of the mountains now only afford sustenance to bees, not so very long ago there were still to be seen roofs of timber cut from trees growing there, which were of a size sufficient to cover the largest houses; and there were many other high trees, cultivated by man and bearing abundance of food for cattle.
Moreover, the land reaped the benefit of the annual rainfall, not as now losing the water which flows off the bare earth into the sea, but, having an abundant supply in all places, and receiving it into herself and treasuring it up in the close clay soil, it let off into the hollows the streams which it absorbed from the heights, providing everywhere abundant fountains and rivers, of which there may still be observed sacred memorials in places where fountains once existed; and this proves the truth of what I am saying.
Such was the natural state of the country, which was cultivated, as we may well believe, by true husbandmen, who made husbandry their business, and were lovers of honour.
Plato gives this description of the frightful erosion already taking place in the fifth century b.c.—but he ascribes almost divine qualities to the husbandmen who obviously caused it. Rather as Ellsworth Huntington did forty years ago, Plato attributed all the trouble not to man but to a change in climate. He thought that what had happened to Attica had been caused by a series of deluges. But I think that if he hadn’t been so interested in platonic ideas and had been a little more concerned with what the husbandmen were actually doing, he probably would have seen that it was precisely these divine husbandmen who had done things to the soil which had left it in the ruined and impoverished state in which the Greeks of his own time found it—and Heaven knows it was relatively fertile then compared to what it is now. One may say that perhaps Plato would have done better to devote more attention to these dreadfully practical problems of nature than to the rather abstract metaphysical problems which engaged him.
And one can say something of the same kind about Socrates, who said that he saw no object in going outside the city walls because everything of interest was within them, and that his business was solely with men. But men do have to live on the soil and live in community with nature, and one wonders whether Socrates wouldn’t have done more good to his fellows if he had paid a little more attention to what went on outside the city walls.
Those of you who are acquainted with the literature of the conservationists will know what an immense amount of land has been destroyed here in an extraordinarily short space of time by wantonness. The same thing is true in many other areas of the world; there are vast areas of erosion in China, in Africa, in South America, and in Southern Europe. And the dreadful process goes on and on, becoming progressively more and more dangerous as more and more people are born into the world and have to be supported and the increasing pressure drives peasants and farmers to attempt to get more and more out of the soil.
The combination of human destructiveness and population increase is an enormous and frightening fact. It is clearly one of the major problems confronting human beings at the present time. But it mustn’t be thought that all people have been destructive all the time and everywhere. On the contrary, in many parts of the world, quite primitive people have shown remarkable understanding of preserving and conserving the soil. I had the opportunity of visiting the Inca regions of the Andes this summer. To see the Inca terraces rising from the floor of the Urubamba River two or three thousand feet up the side of a mountain is an exceptional sight.
Some of this wonderfully cared-for terracing is made with dressed stone, and some of the terraces are used to this day—they permit quite intensive agriculture on incredibly steep slopes (often thirty-five degrees). You go to a place like Machu Picchu, a fantastic city built on a sugarloaf hill, and you discover that its population, which was quite small—probably not more than two or three thousand—was able to survive for two or three centuries at least on its elaborate system of terracing. You will also find extraordinary examples of terracing in Indonesia and the Philippines: among the Igorots in the Philippines there is a wonderful rice cultivation. You will see the same thing in Java, and there is good reason to suppose that many of these rice-growing terraces have been used for a thousand, perhaps even two thousand years.
These are remarkable achievements, but one of the saddest things is to realize that the good examples which some people have set in some parts of the world have certainly not been followed in others. You will find the remains of the ancient pre-Spanish Inca terraces within thirty miles of Cusco, where the worst kind of farming practices have been used in barley cultivation and where the most fearful gullying and erosion is seen. One wonders why on earth modern farmers couldn’t have taken the hint; evidently, as someone said, the greatest lesson of history is that nobody ever learns the lessons of history. Similarly, it is extraordinary that the methods of contour ploughing which are now being applied more and more to agriculture in this country were really not developed until thirty years ago, although a hundred and fifty years ago the process was already apparent to Thomas Jefferson, who talked about soil erosion and soil exhaustion. These facts are all the more disturbing when one realizes that, owing to the increasing pressure of population upon resources, there is extraordinarily little time.
There are several most powerful instruments of soil destruction which man has employed during the ages, but the most disastrous has probably been over-grazing, which has been going on at least since the domestication of sheep and goats—probably seven or eight thousand years. There is a very ironical point here: We generally feel a great sympathy for Abel and a great dislike for Cain, but let us never forget that Abel was the man who had sheep and goats and Cain was the agriculturist. Actually, if there was ever a justified homicide, it
