# Lehre und Wehre_St. Louis Missouri_Dezember 1898_S366
# Machine transcription, uncorrected — CHI Digital Archive (demonstration)

366 Wissenschaften und Glaubensartikel.

f one foot a year would be a much more probable conjecture, and
estimateéd the length of time required for the excavation of the
Whole Niagara ravine at 35,000 years.“ (S. 377 f.) Man beachte
hierbei noch, es sind Conjecturen, die man hat, und noch dazu wie ver⸗
schieden in solcher einfachen Sache!

Aber wir wollen einmal annehmen, die Veränderungen auf der Erd—
oberfläche seien immer so vor sich gegangen, wie wir sie jetzt beobachten,
was wären dann aus den jetzt vor sich gehenden Veränderungen für Schlüsse
zu ziehen? Zunächst müßte — auf welche Weise, das wäre nicht leicht ein—
zusehen — festgestellt werden, von wo an, von welcher Tiefe an die Ver—
änderungen ihren Anfang nehmen. Dann fragen wir weiter, welcher Art
sind die jetzt beobachteten Veränderungen, sind sie einheitlich, sind sie der
Regel nach sehr langsam? Nichts von alledem. Hören wir.

Wie ungleich und oft schnell die Veränderungen an den Mündungen
der Ströme sind, darüber sagt Geikie: „Tbe upper reaches of the
Adriatic sea are being so rapidly shallowed and filled up by the Po.
Adige, and other streams, that Ravenna, originally built in a la-
goon like Venice, is now four miles from the sea, and the port of
Adria so well known in ancient times as to have given its name to
the Adriatic, is now fourteéen miles inland, wihile on other parts of
that coastline the breadth of land gained within the last 1800 years
has béen as mucb as twenty miles. ... It (the Piber) has long been
adding to the coastline at its mouth at the rateé of from 12 to 13 feet
per annum. The ancient harbor of Ostia is now consequently more
than three miles inland.“' (Footnote:) I accompanied the dis-
tinguished French geologist (Prof. Chas. Martins) on the occasion
0 his visit to Ostia in the spring 0of 1873, and was much struck
withe the proofs of the rapidity of deposit in favorable situations.
(S. 390.)

Ueber die Bildung von Torfmooren: The rate of growth of peat
varies within wide limits. An inteéresting exaimple of the formation
and growth of peat-moss in the latter half of the 17thcentury is on
record. In the year 1651 an ancient pine forest oecupied a level
tract of land among the hills in the west of Ross-shire. The trees
were all dead, and in a condition to be blown down by the wind.
About 15 years later every vestige of a tree had disappeared, the
site being occupied by a spongy green bog into which a man would
sink up to the arm-pits. Before the vear 1699 it had become firm
enough to yield good peat for fuel. In a moor in Hanover a layer
of péeat from 4—6 feet thick formed in about 30 years. Near the
lake of Constance a layer of 3— feet grew in 24 years. Among
the Danish mosses à peériod of 250—300 years has beéeen required

to form a layer 10 feet thick.“' (S. 460.) „From the treacherous