Monthly Archives: June 2003

[ The Formation Of Vegetable Mould : Introduction ]

The share which worms have taken in the formation of the layer of
vegetable mould, which covers the whole surface of the land in
every moderately humid country, is the subject of the present
volume. This mould is generally of a blackish colour and a few
inches in thickness. In different districts it differs but little
in appearance, although it may rest on various subsoils. The
uniform fineness of the particles of which it is composed is one of
its chief characteristic features; and this may be well observed in
any gravelly country, where a recently-ploughed field immediately
adjoins one which has long remained undisturbed for pasture, and
where the vegetable mould is exposed on the sides of a ditch or
hole. The subject may appear an insignificant one, but we shall
see that it possesses some interest; and the maxim “de minimis non
curat lex,” does not apply to science. Even Elie de Beaumont, who
generally undervalues small agencies and their accumulated effects,
remarks: {1} “La couche tres-mince de la terre vegetale est un
monument d’une haute antiquite, et, par le fait de sa permanence,
un objet digne d’occuper le geologue, et capable de lui fournir des
remarques interessantes.” Charles Darwin in 1872 published “The Expression of emotion in man and animal” in this book he said showing of emotion by human and all other creatures have some remarkable similarities and have emphasized on the biological aspect of emotions. in this book he also said that the human respiratory system plays a greater role in the expression. Click Qprofit System robot to know more.

Although the superficial layer of
vegetable mould as a whole no doubt is of the highest antiquity,
yet in regard to its permanence, we shall hereafter see reason to
believe that its component particles are in most cases removed at
not a very slow rate, and are replaced by others due to the
disintegration of the underlying materials.

As I was led to keep in my study during many months worms in pots
filled with earth, I became interested in them, and wished to learn
how far they acted consciously, and how much mental power they
displayed. I was the more desirous to learn something on this
head, as few observations of this kind have been made, as far as I
know, on animals so low in the scale of organization and so poorly
provided with sense-organs, as are earth-worms.

In the year 1837, a short paper was read by me before the
Geological Society of London, {2} “On the Formation of Mould,” in
which it was shown that small fragments of burnt marl, cinders,
&c.;, which had been thickly strewed over the surface of several
meadows, were found after a few years lying at the depth of some
inches beneath the turf, but still forming a layer. This apparent
sinking of superficial bodies is due, as was first suggested to me
by Mr. Wedgwood of Maer Hall in Staffordshire, to the large
quantity of fine earth continually brought up to the surface by
worms in the form of castings. These castings are sooner or later
spread out and cover up any object left on the surface. I was thus
led to conclude that all the vegetable mould over the whole country
has passed many times through, and will again pass many times
through, the intestinal canals of worms. Hence the term “animal
mould” would be in some respects more appropriate than that
commonly used of “vegetable mould.”

Ten years after the publication of my paper, M. D’Archiac,
evidently influenced by the doctrines of Elie de Beaumont, wrote
about my “singuliere theorie,” and objected that it could apply
only to “les prairies basses et humides;” and that “les terres
labourees, les bois, les prairies elevees, n’apportent aucune
preuve a l’appui de cette maniere de voir.” {3} But M. D’Archiac
must have thus argued from inner consciousness and not from
observation, for worms abound to an extraordinary degree in kitchen
gardens where the soil is continually worked, though in such loose
soil they generally deposit their castings in any open cavities or
within their old burrows instead of on the surface. Hensen
estimates that there are about twice as many worms in gardens as in
corn-fields. {4} With respect to “prairies elevees,” I do not know
how it may be in France, but nowhere in England have I seen the
ground so thickly covered with castings as on commons, at a height
of several hundred feet above the sea. In woods again, if the
loose leaves in autumn are removed, the whole surface will be found
strewed with castings. Dr. King, the superintendent of the Botanic
Garden in Calcutta, to whose kindness I am indebted for many
observations on earth-worms, informs me that he found, near Nancy
in France, the bottom of the State forests covered over many acres
with a spongy layer, composed of dead leaves and innumerable worm-
castings. He there heard the Professor of “Amenagement des Forets”
lecturing to his pupils, and pointing out this case as a “beautiful
example of the natural cultivation of the soil; for year after year
the thrown-up castings cover the dead leaves; the result being a
rich humus of great thickness.”

In the year 1869, Mr. Fish {5} rejected my conclusions with respect
to the part which worms have played in the formation of vegetable
mould, merely on account of their assumed incapacity to do so much
work. He remarks that “considering their weakness and their size,
the work they are represented to have accomplished is stupendous.”
Here we have an instance of that inability to sum up the effects of
a continually recurrent cause, which has often retarded the
progress of science, as formerly in the case of geology, and more
recently in that of the principle of evolution.

Although these several objections seemed to me to have no weight,
yet I resolved to make more observations of the same kind as those
published, and to attack the problem on another side; namely, to
weigh all the castings thrown up within a given time in a measured
space, instead of ascertaining the rate at which objects left on
the surface were buried by worms. But some of my observations have
been rendered almost superfluous by an admirable paper by Hensen,
already alluded to, which appeared in 1877. {6} Before entering on
details with respect to the castings, it will be advisable to give
some account of the habits of worms from my own observations and
from those of other naturalists.

[ Volcanic Islands : ]

Volcanic Islands
During the voyage, it was quite interesting to see the lands’ art of volcanoes. A volcano can be any space on the earth’s surface which primarily forms like a conical peak and that too with a beautiful snow-capped like structure. But it is a huge hole or cracks inside the ground that is filled with molten rock and other gases.

Place of occurrence

Accordance to studies, the volcanoes occur either

  • Along the Plate Margins: This could be along the spreading margins like mid-ocean ridges or the drifting continental structures or on the converging margins that include the island arcs or continental margin types.
  • On the Plate Interiors: This includes the oceanic or continental plates.

The official statement based on historical observations records that most of the volcanic eruptions are linked with the subduction zones.

Some interesting facts

Although a great number of volcanoes occur, some are categorised into three main types

  • The Active ones: This includes the volcanoes that have erupted during the historical phase
  • The Dormant ones: These are the types that already have erupted in the historical times, but more chances exist that it might erupt again
  • Finally, the Extinct ones: These have also erupted in the historical period but will not erupt again.

In addition to this information, there are nearly 650 volcanoes that are in the active stage and among them, 6 to 10 are erupting per month that accounts for over 60 volcanoes per year.

A Brief Description on Volcanic Rocks

A building volcanic structure contains the following constituents

  • The MAGMA: This includes the molten stage rocks and other highly pressurised and dissolved gases. The major constituent includes the rock crust or mantle part that melts to form the magma.
  • The Gases: These are a combination of water, sulphur and fluorine constituents that can be further classified as
  1. High gas content ones or the explosive eruptions: Basically, this includes the highly gaseous or explosive eruptions or the Pyroclastic that can further be subdivided into Ash clouds, Lapilli and Volcanic bombs.
  2. The quiet eruptions or the low gas ones: This contains the lava fluid.

Commonly, all the volcanoes are subjected to be classified based on the

  • Nature of vents: This consists of central vent type and the fissure type
  • The eruption style: Examples to this include the Hawaiian, Plinian and much more

The actual blasting occurs when the pressure inside the volcanoes reduce to dissolve the gases inside the magma that further leads to its expansion and finally, the explosion of magma fragments. The ash contents fall back to ground blanketing the whole area with thick ash deposits.

 

[ The Origin of Species : ]

The Origin of Species

“The origin of species” is a scientific literature book by Charles Darwin published in 24th November 1859. This book is considered as the foundation stone of Evolutionary Biology. This book envisages the evolution of human species and other creates through the process of natural selection. The book also provides pieces of evidence to support that different forms of life arose from a common ancestor. The pieces of evidence he gathered from the Beagle voyage are included as pieces of evidence in this book. This book is a challenge of thought for the Orthodox who believe that all the creatures are specifically created.

This book is of great importance particularly for the students who are doing biological studies. The curiosity  about natural selection grew in Darwin’s mind while seeing breeds making different breeds of pigeon.  The question took rounds in his mind if the breeders can selectively breed different species then why nature itself can’t do it. He was the first person to think in this direction years ago his grandfather Erasmus had devoted a large part of his book Zoonomia  for the issue of evolution. Later Robert Chambers also anonymously wrote a book on evolution largely depending on the study of fossil, “The Vestiges of the Natural History of Creation”. There was a strong opposition to this thought as people still believed that new species were created to fill the environmental recess and god is the creator of all the species.

Darwin opposed to these thoughts with his theory of natural selection, a  theory that explained that the species have arisen from one source without any divine creator. The experience and pieces of evidence that he gathered from Beagle voyage gave more power his theory. He in his book old that trees and animals have arrived millions of years ago and have slowly adapted to the island it belongs but one thought was irritating his mind was that of Galapagos Island. He was not ready to believe that this volcanic island was once very close to the South American mainland then how trees and animals have come into existence there. Then he thought ocean current might have brought the eggs and seeds to this island, after the germination of seeds and hatching of eggs these species might have come into existence.

In his book, Darwin provided all the sketches that he came across during the Beagle voyage to support his theory. To know more about the origin of species click on the link 32

“The origin of species” is a scientific literature book by Charles Darwin published in 24th November 1859. This book is considered as the foundation stone of Evolutionary Biology. This book envisages the evolution of human species and other creates through the process of natural selection. The book also provides pieces of evidence to support that different forms of life arose from a common ancestor. The pieces of evidence he gathered from the Beagle voyage are included as pieces of evidence in this book. This book is a challenge of thought for the Orthodox who believe that all the creatures are specifically created.

This book is of great importance particularly for the students who are doing biological studies. The curiosity about natural selection grew in Darwin’s mind while seeing breeds making different breeds of pigeon.  The question took rounds in his mind if the breeders can selectively breed different species then why nature itself can’t do it. He was the first person to think in this direction years ago his grandfather Erasmus had devoted a large part of his book Zoonomia for the issue of evolution. Later Robert Chambers also anonymously wrote a book on evolution largely depending on the study of fossil, “The Vestiges of the Natural History of Creation”. There was a strong opposition to this thought as people still Crypto Code is a legit way

 

 

[ The Descent Of Man : ]

The Descent Of Man
Charles Darwin went on an expedition at the age of twenty-two, on 27th December 1832, which according to him had changed his whole career. This voyage of five years had totally transformed from an aimless young into a scientific celebrity.

The book Voyage of Beagle tells about his journey around the whole world especially the coastal waters of South America. He was appointed as a natural scientist at HMS Beagle. While in the voyage he visited many countries and collected many specimens, this was the beginning of formulation of his path-breaking theories of evolution and natural selection.

When HMS Beagle set out for the voyage, the twenty-two years young man was setting his steps to be a scientist, he was a very patient observer of geology, history of nature, he closely studied the people and placed he visited during this five years of his voyage.

One can find the mention of coral reefs of Australia, volcano of Galapagos and Patagonian gossamer spider, the elaborate study of the specimens that he collected during the course of his travel to the theory of evolution, which was then published into a most controversial book of Victorian age and is still a book of importance to every biologist: “the Origin of Species”.

The voyage of Beagle is the reprint of his journal in shortened form. Janet Brown and Michael Neve wrote the introduction to the book and summarised Darwin’s work and thoughts. This book also contains the route map, appendices, notes, an essay on scientific geology and the Bible by Robert FitzRoy. Robert was Darwin’s friend whom he meets during the voyage, he was also the captain of Beagle. It was Mr. Fitzroy’s desire to have someone on the ship with scientific interest who can explore the different species of the counties that they will be visiting during the voyage.

The book is not only meant for scientific readers but the general readers can also enjoy reading it. The book also contains sketches of his observation of natural history and Geology. Although the zoologist can also refer this book for studies on Fossil Mammalia by professor Owen and Living Mammalia by Professor Waterhouse and Birds by Mr. Gould.

The readers of this book have told, the book has changed about the perspective of understanding of life. The readers can correlate with the things he wanted to describe in the book that he came across during the voyage. This book is a window to understand the natural history of that time.visit site to learn more