The Earth As Modified By Human Action Part 38

These heaps formed almost a complete rampart around the city, and impeded both the circulation of the air and the communication between Cairo and its suburbs. At two points these acc.u.mulations are said to have risen to the incredible height of between six and seven hundred feet; and these two heaps covered two hundred and fifty acres.

[Footnote: Clot Bey, Egypte, i., p. 277.] During the occupation of Cairo by the French, the invaders constructed redoubts on these hillocks which commanded the city. They were removed by Mehemet Ali, and the material was employed in raising the level of low grounds in the environs.

[Footnote: Egypt manufactures annually about 1,200,000 pounds of nitre, by lixiviating the ancient and modern rubbish-heaps around the towns.]

In European and American cities, street sweepings and other town refuse are used as manure and spread over the neighboring fields, the surface of which is perceptibly raised by them, by vegetable deposit, and by other effects of human industry, and in spite of all efforts to remove the waste, the level of the ground on which large towns stand is constantly elevated. The present streets of Rome are twenty feet, and in many places much more, above those of the ancient city. The Appian Way between Rome and Albano, when cleared out a few years ago, was found buried four or five feet deep, and the fields along the road were elevated nearly or quite as much. The floors of many churches in Italy, not more than six or seven centuries old, are now three or four feet below the adjacent streets, though it is proved by excavations that they were built as many feet above them. [Footnote: Rafinesque maintained many years ago that there was a continual deposition of dust on the surface of the earth from the atmosphere, or from cosmical s.p.a.ce, sufficient in quant.i.ty to explain no small part of the elevation referred to in the text. Observations during the eclipse of Dec. 22, 1870, led some astronomers to believe that the appearance of the corona was dependent upon or modified by cosmical dust or matter in a very attenuated form diffused through s.p.a.ce.

Tyndall has shown by optical tests that the proportion of solid matter suspended or floating in common air is very considerable, and there is abundant other evidence to the name purpose. Ehrenberg has found African and even American infusoria in dust transplanted by winds and let fall in Europe, and Schliemann offers that the quant.i.ty of dust brought by the scirocco from Africa is so great, that by cutting holes in the naked rocks of Malta enough of Libyan transported earth can be caught and retained, in the course of fourteen years, to form a soil fit for cultivation.--Beilage zur Allgemeinen Zeitung, Mar. 24, 1870.]

Nothing Small in Nature.

It is a legal maxim that "the law concerneth not itself with trifles,"

de minimis non curat lex; but in the vocabulary of nature, little and great are terms of comparison only; she knows no trifles, and her laws are as inflexible in dealing with an atom as with a continent or a planet. [Footnote: One of the sublimest, and at the same time most fearful suggestions that have been prompted by the researches of modern science, was made by Babbage in the ninth chapter of his Ninth Bridgewater Treatise. I have not the volume at hand, but the following explanation will recall to the reader, if it does not otherwise make intelligible, the suggestion I refer to:

No atom can be disturbed in place, or undergo any change of temperature, of electrical state, or other material condition, without affecting, by attraction or repulsion or other communication, the surrounding atoms.

These, again, by the same law, transmit the influence to other atoms, and the impulse thus given extends through the whole material universe.

Every human movement, every organic act, every volition, pa.s.sion, or emotion, every intellectual process, is accompanied with atomic disturbance, and hence every such movement, every such act or process, affects all the atoms of universal matter. Though action and reaction are equal, yet reaction does not restore disturbed atoms to their former place and condition, and consequently the effects of the least material change are never cancelled, but in some way perpetuated, so that no action can take place in physical, moral, or intellectual nature, without leaving all matter in a different state from what it would have been if such action had not occurred. Hence, to use language which I have employed on another occasion: there exists, not alone in the human conscience or in the omniscience of the Creator, but in external nature, an ineffaceable, imperishable record, possibly legible even to created intelligence, of every act done, every word uttered, nay, of every wish and purpose and thought conceived, by mortal man, from the birth of our first parent to the final extinction of our race; so that the physical traces of our most secret sins shall last until time shall be merged in that eternity of which not science, but religion alone a.s.sumes to take cognisance.]

The human operations mentioned in the last few paragraphs, therefore, do act in the ways ascribed to them, though our limited faculties are at present, perhaps forever, incapable of weighing their immediate, still more their ultimate consequences. But our inability to a.s.sign definite values to these causes of the disturbance of natural arrangements is not a reason for ignoring the existence of such causes in any general view of the relations between man and nature, and we are never justified in a.s.suming a force to be insignificant because its measure is unknown, or even because no physical effect can now be traced to it as its origin.

The collection of phenomena must precede the a.n.a.lysis of them, and every new fact, ill.u.s.trative of the action and reaction between humanity and the material world around it, is another step towards the determination of the great question, whether man is of material nature or above her.

THE END