The Elements of Geology; Adapted to the Use of Schools and Colleges
CHAPTER II.
SECTION I.
What is the primary division of rocks?
Upon what principle are the unstratified rocks divided?
Upon what principle are the stratified rocks divided?
Why are the non-fossiliferous called metamorphic rocks?
Name the four classes of rocks.
SECTION II.
What is the most abundant plutonic rock?
How is its thickness ascertained?
What is its amount?
Where is it found?
What is its ordinary structure?
What peculiarity of structure facilitates the cleavage of granite?
The granitic masses are generally deep below the surface; in what other position does granite appear?
In what classes of rocks are granite veins found?
Were they all produced at the same time?
How is this demonstrated?
What is the relative position of the older and newer granites?
What other plutonic rocks occur in considerable quantities?
SECTION III.
Of what do volcanic rocks consist?
In what states are they ejected?
What are the principal varieties of lava, and how are they distinguished?
Why is the basaltic lava the last to be ejected?
How is the age of the volcanic rocks determined?
What are the three divisions of the volcanic rocks, as dependent upon age?
What is the proportion of the volcanic to other rocks?
How many active volcanoes exist?
Describe the eruptions of Kilauea.
Describe the eruption in Iceland in 1783.
What are the dimensions of Mount Ætna, and how has it been produced?
How are the tertiary lavas known to be such?
Where have they been most studied?
What is the evidence that these rocks in France are volcanic?
Have these lavas been produced within the historic period?
Were they produced at an early period in the earth's history?
Give the evidence that their activity was long-continued.
What is the form of the earlier volcanic rocks?
What circumstances distinguish the trappean from other volcanic rocks?
What are some of the prominent localities of the trappean rocks?
How do they occur in the islands west of Scotland?
How in the valley of the Connecticut river?
SECTION IV.
What is the lowest metamorphic rock?
Describe it.
How does mica slate differ from gneiss?
Is it well distinguished from argillaceous slate?
What is the third rock in the metamorphic series?
Why is it difficult to determine the upper limit of this series?
Why do the principal rocks of this series occur in the order here given?
What other rocks may take the place of these principal rocks?
Where do the metamorphic rocks occur?
What is their thickness and amount?
SECTION V.
How many systems of fossiliferous rocks are there, and what are they?
What other system is provisionally introduced?
What is its position?
Describe it.
What materials of value are obtained from this system?
What fossils does it contain?
In what localities is it found?
What explanation, in reference to these rocks, is given by those who deny that they constitute a distinct system?
In what respects does the State of New York present the best facilities for studying the Silurian system?
Describe the Champlain division.
The Ontario division.
The Helderberg division.
Describe the Erie division.
What are the fossils of this system?
Describe the Crinoidea.
The Cephalopoda, and the two forms.
The Trilobite.
What higher forms of animal life existed during the silurian period?
The geographical range of the system?
Of what does the Old Red Sandstone consist?
Describe its three divisions.
What are its fossils?
Describe the fishes of that period.
What was the peculiarity of the Pterichthys?
Of the Cephalaspis?
Where are the rocks of this system found?
How is the carboniferous system divided?
Describe the carboniferous limestone.
What ores are found in it?
Describe, its fossils.
Describe the millstone grit.
Of what do the coal measures consist?
How does the ironstone occur?
Describe the coal beds.
How is the continuity of the strata interrupted?
What variations from this general type occur in the formation?
Describe the several varieties of coal.
How is the coal quarried?
What mineral springs occur in this formation?
To what uses is coal applied?
(The coal was deposited thousands of years ago, and has served no useful purpose, that we know of, till very recently. Its formation was planned and completed to meet a want which was not to be felt till the lapse of many ages. It is a notable instance of the wisdom and forethought, as well as of the benevolence, of God.) In what does this prospective arrangement consist? What are the character and position of the fossils of the coal measures?
What are the four most abundant forms?
Describe the Stigmaria. The Sigillaria. The Lepidodendron. The Calamite.
Where are the beds of coal found?
What is the fourth formation of rocks?
Into what two portions is it divided?
Of what does the Permian portion consist?
The Trias?
What minerals are found in this formation?
What springs?
What fossils?
How are the fishes of the earlier and later portions distinguished?
What peculiarity of the red sandstones is mentioned?
By what kinds of animals were the tracks, which they contain, made?
Give localities of the new red sandstone.
What are the three divisions of the Oölitic system?
Describe the Lias.
The Oölite.
The Wealden.
What are the general peculiarities of the system?
What are the fossil animals of the system?
By which class of fossil animals is the system characterized?
Describe the Ichthyosaurus. The Plesiosaurus. Pterodactyle. The Iguanodon.
Where is the system developed?
What are the divisions of the Cretaceous system?
How are the layers of chalk separated?
What is the geological position of the Neocomian system, and the greensand of this country?
What are the fossils of this system?
What the geographical range?
How are the tertiary deposits distinguished from the older formations?
Upon what principle is the tertiary system divided?
What are these divisions called, and what does each, name signify?
In what portion of the tertiary period was the drift deposited
What is the geographical range of the drift?
Of what does it consist?
What is the latest tertiary deposit?
What are the fossils of the tertiary system?
Describe the Paleotherium. The Anoplotherium. The Megatherium. The Mastodon. The Mammoth.
What other animals belonged to this period?
Where are the tertiary deposits found?
What formations are regarded as recent?
What formations of this class are accessible?
What others are in progress?
What are the fossils of this formation?
SECTION VI.
What is a fossil?
In what ways are they preserved?
When is a fossil said to be mineralized?
Describe the process of mineralization.
How is it proved that the removal of the organic matter and substitution of mineral particles are simultaneous?
Were animals created before vegetables?
How is this shown?
At what period was the vegetable growth the greatest?
What forms of animal life were most abundant during the earlier periods?
What vertebrated animals belonged to these periods?
What advance is made in the new red sandstone period?
During what period do the mammalia first appear in abundance?
During what geological period was man created?
How are the footprints and skeletons of human beings hi solid rocks accounted for?
Why are not fossils distributed uniformly through all the formations, and through all the parts of each formation?
In what does the importance of fossils consist?
How are the fresh-water and marine formations distinguished?
What circumstances render it difficult to identify rocks of the same age in different localities?
How are formations identified?
Was the work of creation one of short duration?
What was the last work of creation of which we have any geological evidence?
Why may we presume that no more species will be created?
Do all the animal and vegetable species which have been created still exist?
What causes are operating to destroy species?
SECTION VII.
How long has it been since the creation of the earth?
How does the amount of stratified rock indicate the great antiquity of the earth?
How does the stratification show the same thing?
What is the proof that the principal strata were deposited before the creation of man, and how does this fact bear upon the question of the antiquity of the earth?
Give the argument drawn from the successive creations and disappearance of animal and vegetable species.
The argument drawn from the amount of organic matter in the stratified rocks.
The argument from slow accumulation.
What is the general conclusion from these facts?
Why is this conclusion an important one?
What objection to it has been raised?
How is this objection answered?
What additional explanation is given?