Delta 

 Denial 



SCIENTIFIC SIDE-LIGHTS 



156 



particles of mud not settling at the mouths 

 of the river, but being swept out far to sea 

 during the predominant action of the tides 

 and the waves in the winter months, when 

 the current of fresh water is feeble. Yet, 

 however vast the time during which the 

 Mississippi has been transporting its earthy 

 burden to the ocean, the whole period, tho 

 far exceeding, perhaps, 100,000 years, must 

 be insignificant in a geological point of view, 

 since the bluffs or cliffs bounding the great 

 valley, and therefore older in date, and 

 which are from 50 to 250 feet in perpendicu- 

 lar height, consist in great part of loam con- 

 taining land, fluviatile, and lacustrine shells 

 of species still inhabiting the same country. 

 LYELL Principles of Geology, bk. ii, ch. 

 18, p. 273. (A., 1854.) 



761. DELUGES, ANCIENT TRADI- 

 TIONS OF Floods of Ogyges and Deucalion. 

 The traditions which have come down to 

 us from remote ages of great inundations, 

 said to have happened in Greece and on the 

 confines of the Grecian settlements, had 

 doubtless their origin in a series of local 

 catastrophes, caused principally by earth- 

 quakes. The frequent migrations of the 

 earlier inhabitants, and the total want of 

 written annals long after the first settlement 

 of each country, make it impossible for us at 

 this distance of time to fix either the true 

 localities or probable dates of these events. 

 The first philosophical writers of Greece 

 were, therefore, as much at a loss as our- 

 selves to offer a reasonable conjecture on 

 these points, or to decide how many catas- 

 trophes might sometimes have become con- 

 founded in one tale, or how much this tale 

 may have been amplified, in after times, or 

 obscured by mythological fiction. The floods 

 of Ogyges and Deucalion are commonly said 

 to have happened before the Trojan war; 

 that of Ogyges more than seventeen and 

 that of Deucalion more than fifteen cen- 

 turies before our era. As to the Ogygian 

 flood, it is generally described as having laid 

 waste Attica, and was referred by some wri- 

 ters to a great overflowing of rivers, to which 

 cause Aristotle also attributed the deluge of 

 Deucalion, which, he says, affected Hellas 

 only, or the central part of Thessaly. Oth- 

 ers imagined the same event to have been 

 due to an earthquake, which drew down 

 masses of rock, and stopped up the course of 

 the Peneus in the narrow defile between 

 mounts Ossa and Olympus. LYELL Prin- 

 ciples of Geology, bk. ii, ch. 22, p. 356. (A., 

 1854.) 



762. DELUSION BY SYSTEM Logic 

 Disregarding Fact. Yet the essential and 

 fundamental error of this [former medical] 

 system was, and still continued to be, the 

 false kind of logical conclusion to which it 

 was supposed to lead; the conception that 

 it must be possible to build a complete sys- 

 tem which would embrace all forms of dis- 



ease, and their cure, upon any one simple 

 explanation. HELMIIOLTZ Popular Lectures, 

 lect. 1, p. 212. (L. G. & Co., 1898.) 



763. DELUSIONS BENEFICENT Al- 

 chemy Led to Chemistry Greatness in 

 Spite of Errors. Albertus Magnus, of the 

 family of the Counts of Bollstadt, must be 

 mentioned as an independent observer in the 

 domain of analytic chemistry. It is true 

 that his hopes were directed to the transmu- 

 tation of the metals, but in his attempts to 

 fulfil this object he not only improved the 

 practical manipulation of ores, but he also 

 enlarged the insight of men into the general 

 mode of action of the chemical forces of Na- 

 ture. His works contain some extremely 

 acute observations on the organic structure 

 and physiology of plants. He was ac- 

 quainted with the sleep of plants, the pe- 

 riodical opening and closing of flowers, the 

 diminution of the sap during evaporation 

 from the surfaces of leaves, and with the in- 

 fluence of the distribution of the vascular 

 bundles on the indentations of the leaves. 

 . . . In his own observations, we, how- 

 ever, unhappily too often find that Albertus 

 Magnus shared in the uncritical spirit of his 

 age. He thinks he knows " that rye changes 

 on a good soil into wheat; that from a 

 beech-wood which has been hewn down a 

 birch-wood will spring up from the decayed 

 matter; and that from oak branches stuck 

 into the earth vines arise." . . . The work 

 of Albertus Magnus, entitled " Liber Cosmo- 

 graphicus de Natura Locorum," is a kind of 

 physical geography. I have found in it ob- 

 servations which greatly excited my sur- 

 prise, regarding the simultaneous depend- 

 ence of climate on latitude and elevation, 

 and the effect of different angles of incidence 

 of the sun's rays in heating the earth's sur- 

 face. HUMBOLDT Cosmos, vol. ii, pt. ii, pp. 

 243-4. (H., 1897.) 



764. Columbus Aided by 



Ancient Medieval Error Ocean Supposed 

 Less than Land. In the present condition 

 of the surface of our planet, the area of 

 the solid is to that of the fluid parts as 

 l:2fths (according to Rigaud, as 100:270). 

 The islands form scarcely ^d of the conti- 

 nental masses, which are so unequally di- 

 vided that they consist of three times more 

 land in the northern than in the southern 

 hemisphere, the latter being, therefore, pre- 

 eminently oceanic. . . . When we con- 

 sider that nearly three-fourths of the upper 

 surface of our planet are covered with water, 

 we shall be less surprised at the imperfect 

 condition of meteorology before the begin- 

 ning of the present century. ... In the 

 Middle Ages the opinion prevailed that the 

 sea covered only one-seventh of the surface 

 of the globe, an opinion which Cardinal 

 d'Ailly (" Imago Mundi," cap. 8) founded on 

 the fourth apocryphal book of Esdras. Co- 

 lumbus, who derived a great portion of his 

 cosmographical knowledge from the cardi- 

 nal's work, was much interested in uphold- 



