BRICKS, MORTAR, GRANITE, SLATE, LIMESTONE, OR CALCAREOUS ROCKS,
STEEL, EARTHS, VOLCANOES, AND EARTHQUAKES.
Of what are Bricks composed?
Of clay, dried by the heat of the sun, or burnt in kilns; their color
varies with the different degrees of heat to which they are subjected
in burning. In the East, bricks were baked in the sun; the Romans used
them crude, only laying them to dry in the air for a long space of
time.
_Crude_, in the rough, unbaked state, just as they were
formed.
How long have Bricks been in use for building?
Bricks appear to have been in use at a very remote period of
antiquity, both from the account of them in the Holy Scriptures, and
from the remains of them which have been found; the Tower of Babel and
the walls of Babylon were built of them. They were in early use among
the Egyptians, as appears from the history of the Jews before their
deliverance by Moses. In the book of Exodus, we are told that this
captive people were compelled to make bricks for that nation. The
Romans, under their first kings, built with massive square stones; but
towards the end of the Republic they began to use brick, borrowing the
practice from the Greeks; and the greatest and most durable buildings
of the succeeding Emperors were composed of them, as the Pantheon, &c.
_Massive_, bulky and heavy.
By whom was the Tower of Babel erected, and why?
By the descendants of Noe's three sons, Sem, Cham, and Japheth; they
were extremely numerous, and dwelt in the land of Sennaar; becoming
ambitious of distinguishing themselves, they set about building a
tower whose summit might reach to heaven. Sennaar was the original
name of the country about Babylon.
_Descendants_, those descended from a particular person or
family.
What remarkable event followed their foolish pride?
The Almighty suddenly frustrated their purpose by confusing their
language and causing them all to express their words by different
sounds; hence arose the numbers of different languages spoken by the
nations of the earth; and thus what they imagined would be a monument
of glory, was made an awful memento of their pride and folly.
_Frustrated_, prevented.
_Monument_, anything by which the memory of persons or
things is preserved.
_Memento_, a hint to awaken the memory of anything; that
which reminds.
What good effect did this event produce?
God, who at all times can bring good out of evil, by this means caused
the other parts of the earth to be peopled; for this visitation having
effectually broken up their scheme, they emigrated in parties, and
dispersed themselves over different parts of the world.
_Scheme_, plan, intention.
_Emigrated_, removed from one country to another.
_Dispersed_, separated.
Where was Babylon?
This celebrated city, so often mentioned in Holy Writ, (and remarkable
for the minuteness with which its destruction was foretold by the
Prophets,) was the capital of the Assyrian Empire, and situated on the
river Euphrates. After the destruction of Nineve, the ancient capital
of this empire, Babylon became the most famous city of the East.
_Minuteness_, particularity.
What is meant by the Assyrian Empire?
The country of Assyria, in Asia.
For what was this city particularly celebrated?
For its hanging gardens, palaces, temples, and walls, the latter of
which are said to have been three hundred and fifty feet high, and so
broad that six chariots could go abreast upon them. The city was so
strongly fortified, both by nature and art, as to be thought
impregnable.
_Fortified_, defended.
_Impregnable_, incapable of being taken or destroyed by an
enemy.
By whom was it destroyed, and when?
By Cyrus, 538 years before the birth of Christ, just fifty years after
Nabuchodonosor had destroyed the city of Jerusalem and its temple.
Who was Cyrus?
The founder of the Persian Empire.
Who was Nabuchodonosor?
The King of Babylon.
What was the Pantheon?
A temple of a circular form which was dedicated to all the Gods, or
all the Saints. That of all others the most celebrated, is the
Pantheon of ancient Rome, and its remains are the most perfect amongst
the wonders of that city at the present day.
_Circular_, having the form of a circle, round.
By whom was it built?
By Agrippa, the Consul of Rome, twenty-five years before Christ; it
was dedicated by him to Jupiter: the name Pantheon was given on
account of the great number of statues of the Gods ranged in niches
all round it; and because it was built in a circular form to represent
heaven, the residence of the Gods. It was afterwards converted into a
church by Pope Boniface IV, and dedicated to the Blessed Virgin and
all the Martyrs, under the title of "Our Lady of the Rotunda." Agrippa
likewise built the Pantheon at Athens, which was but little inferior
to that of Rome. The Greek Christians afterwards converted it into a
church, dedicating it to the Blessed Virgin; but the Turks, when they
subdued Greece, changed it into a mosque.
_Dedicated_, appropriated to a particular person, or to a
sacred use.
_Residence_, dwelling, habitation.
_Martyr_, one who is put to death for the cause of religion.
_Mosque_, a Mahommedan temple.
[Illustration: A SLATE QUARRY.]
What is understood by a Consul?
The chief magistrate of the Roman republic or commonwealth. After the
Romans had expelled their kings, they were governed by two Consuls;
these were established in the year of Rome 245. The Consuls were the
head of the senate; they commanded the armies of the republic, and
judged all the differences between the citizens: they held their
office for the space of a year; at the end of which time, new ones
were elected. Consuls were even continued under the Emperors after the
republic was destroyed; but it was then little more than an honorary
title, and at last was totally abolished.
_Expelled_, turned out.
_Abolished_, annulled, made void.
To what is the term Consul applied at the present time?
To an officer established by a commission from a king or state, to
reside in foreign countries of any considerable trade, to facilitate
and despatch business, protect the merchants of the state, &c.
_Commission_, a trust imposed, command, authority.
_Facilitate_, to render easy.
What is meant by a Senate?
An assembly or council of senators, that is, of the principal
inhabitants of a state, who have a share in the government.
What is the government of the United States?
It is one of limited and definite powers, defined by a written
constitution.
How are the legislative powers, granted to the government, vested?
In a Congress, consisting of a Senate of two Senators from each state,
chosen by the legislature thereof; and a House of Representatives,
consisting of one or more members from each state, elected by the
people in equal electoral districts.
_Legislative_, giving or enacting laws
How are our laws made?
Bills passed by the House of Representatives and the Senate, on
receiving the sanction of the President, become laws; or, if vetoed by
the President, may be passed by two-thirds of both Houses.
_Vetoed_, withheld assent to.
Who was Jupiter?
The principal deity of the Pagan world.
What is used to cement bricks firmly together?
Mortar; a composition of lime, sand, gravel, &c., mixed up with water;
the ancients had a kind of mortar so very hard and binding, that, even
to this day, it is next to impossible to separate the parts of some of
their buildings.
What is Granite?
A rock which has been formed by the union of three different minerals
in a state of fusion; these, on cooling, have crystallized and become
distinct from each other in the mass. It is remarkable for the beauty
of its colors, its hardness and durability. There are granites of many
different colors, as red or rose-colored, grey, green, variegated, &c.
_Fusion_, a melted state.
_Mass_, a body, a lump.
What form does it bear?
Granite does not, generally, form one extensive mass, but remains in
separate and large fragments, rudely compacted together; besides the
three minerals of which it is composed, particles of other stones, or
metallic earths, are often accidentally mixed with it. It is called
granite from its granulous structure.
_Compacted_, joined together.
_Granulous_, consisting of small grains.
Where is Granite found?
Granite occurs in all the larger mountain ranges, and in isolated
masses in every country; not being a stratified rock, and being
excessively hard, it is difficult to get it out in manageable masses.
In Arabia Petræa, the whole country abounds in masses of different
granites.
_Isolated_, alone, separated, detached.
_Stratified_, consisting of strata or beds.
What mode is usually employed in this country in obtaining it?
Blasting, or blowing up with gunpowder; the force of which detaches
pieces from the rock, which are hewn roughly into forms on the spot by
a small pickaxe. Granite is also quarried by cutting a deep line some
yards long, and placing strong iron wedges at equal distances along
this line; these wedges are struck in succession with heavy hammers,
till the mass splits down. Another method of detaching masses of rock,
is by driving wooden wedges into a deep artificial or natural crack,
or fissure; the wedges are then wet, and, in consequence of swelling,
burst the rock asunder.
_Quarried_, from _to quarry_, a term used for the getting of
stone from a quarry, or place where stones are dug from the
earth, or detached from a large mass of rock.
_Detach_, to separate.
For what is this Rock used?
On account of its great hardness, it is used for large public
structures, as bridges, churches, &c. The ancient temples and other
buildings in Egypt, Asia, and Italy, were built of different colored
granites, especially the beautiful Oriental red granite.
What is Slate?
The common name for a bluish fossil stone, very soft when dug out of
the quarry, and easily cut or split into thin plates,--a property
which renders it invaluable for a variety of purposes.
_Invaluable_, extremely valuable.
For what is it used?
Slate has superseded the use of lead for covering roofs, even of the
largest buildings; being lighter and more durable, it is preferable to
tile: it is also employed for slabs to form cisterns, shelves for
dairies, and other purposes, on account of its strength, coolness, and
the ease with which it can be cleaned; the latter quality renders it
also of great value in the business of education, as a cheap
substitute for paper. The ancients were unacquainted with the use of
slate.
What other kinds of stone are used in building?
Limestone, or the calcareous rocks of the geologist: of these there
are many varieties. Those which are easily cut and polished are termed
marbles, and are used in sculpture and in ornamental architecture. The
coarser marbles are used for the common purposes of building.
_Calcareous_, partaking of the nature of calx or lime,--a
term employed to describe chalk, marble, and all other
combinations of lime with carbonic acid.
_Geologist_, one who studies the science of Geology.
Of what do Calcareous Earths or Stones consist?
Calcareous earths, stones, or rocks consist of lime, or pure
calcareous earth, carbonic acid, and water.
What is Quick-Lime?
Limestone deprived of its carbonic acid and water by being subjected
to an intense heat in a kiln.
How are these Stones wrought?
To whatever purpose the stones are to be applied, the larger blocks
obtained from the quarry must be cut into smaller and more manageable
pieces by sawing: the saw used is a long blade of steel, without
teeth, fixed in a heavy wooden frame. These huge saws are worked by
one or two men who sit in boxes to shelter them from the weather;
water is caused to drip constantly into the cut, to facilitate the
motion of the saw, and keep it cool, so as to prevent it from losing
its temper.
_Huge_, very large.
_Temper_, hardness; in speaking of metals it signifies the
state to which they are reduced, especially with regard to
their hardness.
What is Steel?
Iron combined with a small portion of carbon; its chemical name is
_Carburet of Iron_. It is not so malleable as iron in its ordinary
state; but is much harder, more elastic, and susceptible of a higher
polish. Of this material are manufactured knives, swords, and all
kinds of cutting instruments and edge tools, used for domestic
purposes and in the arts, from the ponderous pit-saw to the finest
lancet. Good steel is much more ductile than iron; and a finer wire
may be drawn from it than from any other metal. The excellence of
edge-tools depends upon their temper.
_Ponderous_, heavy.
You say that a Geologist is one who studies Geology: what is meant by
this term?
A science which enables us to read, in the simple language of nature,
the changes which have taken place on the surface of the earth, in its
structure and mineral constitution. It describes the different
materials and the strata of which the crust of the earth is composed,
and investigates the causes of its physical features.
_Simple_, easily read.
What are Strata?
Layers of rocks and other substances of which the whole earth seems to
be composed. These rocks are found lying one above another in regular
order; beneath them are the _unstratified_ rocks, which seem to form
the basis or foundations upon which the others have been deposited.
The various layers seem to have been formed during progressive stages
of vegetable and animal organization. These rocks and strata are
divided into five classes or formations.
_Progressive_, moving forwards.
_Organization_, formation or structure of bodies.
Name them.
The Primitive, or lower formations, supposed to have been formed in
the chaotic state of the earth, because they have no trace of
organized beings or petrifactions; they are chiefly composed of
silicious and argillaceous earths, as granite, slate, &c.--Transition
rocks, supposed to have been formed during the transition of the earth
into a habitable state; they differ from the primitive, in containing
the remains of marine animals:--the Secondary rocks, containing the
remains of animals and vegetables, and consequently formed after their
creation;--the Tertiary formation, composed of layers of clay, sand,
gravel, and marl, and containing peculiar organic remains;--and the
Alluvial formation, constituted of parts of previous rocks separated
by water, &c., and deposited in beds.
_Petrifaction_, an animal or vegetable substance turned to
stone.
_Silicious_, consisting of flint.
_Transition_, change from one state to another.
_Argillaceous_, clayey, consisting of clay.
_Chaotic_, resembling chaos, confused.
_Chaos_, confusion, a mingled heap; a term used in speaking
of the world while yet without form; a Greek word,
signifying a confused mass.
_Alluvial_, deposited from water.
Of what is this last compounded?
The Alluvial formation is composed of sand, gravel, loam, clay, turf,
&c., and contains plants, roots, moss, bones, petrified wood, and
skeletons of animals. It is distinguished from the Tertiary formation
chiefly by its superior position, and by extending over regions where
existing streams or other causes now in action could have produced it.
Some geologists mention another formation called the Volcanic, because
composed of minerals thrown from the crater of a volcano, such as
pumice stones, lava, &c.
_Crater_, the mouth or opening of a volcano.
_Petrified_, hardened into stone.
You mentioned Silicious and Argillaceous Earths: is not, then, the
earthy covering of our globe of one common character?
No; by earth is understood a combination of many distinct bodies.
Chemists, by separating earths from each other, and from foreign
matters connected with them, have discovered nine or ten primitive
earths; all of these, except silex, are compounds of oxygen with
metallic bases.
_Chemist_, one who understands the science of chemistry.
Of which of these Simple or Primitive Earths are the solid portions of
the globe principally composed?
Of flint or silex, lime or calcareous earth, and clay or argil, in
various degrees of combination, the greatest parts of the mountains
and plains, and the whole of what we commonly understand by soil,
mould, earth, &c. are composed. These, however, though forming nearly
all of the solid portions of the world, are constantly mixed with
foreign matters, as metals, (particularly iron,) and acids, (as
carbonic acid.)
What are the properties of Silex?
Silex, or pure flint, will not dissolve in water, nor can it be melted
by itself in any heat; but combined with alkalies, as soda or potash,
it forms glass. It is the principal ingredient of most of the precious
stones.
What are the chief uses of Silex?
It is the most durable article for the formation of roads; a necessary
ingredient in earthenware, porcelain, and cements; and the principal
material of glass and vitreous substances. The making of pastes or
artificial gems is a branch of the art of glass-making; the basis used
is a very hard and pure silex.
_Basis_, that part of any mixture which is the ground or
base; the first principle or element of a substance.
Describe the properties of Lime.
It is of a white color, and possesses a hot, caustic taste. It forms
peculiar salts with acids; changes vegetable blues to green; will not
fuse; gives out a quantity of caloric when united with water; and
absorbs carbonic acid when exposed to air. Lime is very useful in the
arts and manufactures, in medicine, &c. The farmers use it as manure
to fertilize land.
_Caustic_, burning, corroding: a term applied to substances
which eat away and burn any thing with which they are
brought in contact.
In what state is Lime found in nature?
Never native, but combined with other substances;--generally with an
acid, and most plentifully with carbonic acid, as in chalk, marble,
&c. It is also found in vegetables, and is the basis of animal bones;
it likewise occurs in the water of the ocean, and in that of all
springs and rivers. The method of procuring _lime_, from chalk,
marble, limestone, oyster-shells, &c., has already been described in a
former chapter.
What are the properties of Clay?
Argil, or pure clay, also called _alumina_, from its being the basis
of alum, is soft to the touch, adhesive, and emits a peculiar odor
when moistened;--forms a paste with water, and hardens in the fire.
Its uses are so various and important, that it would have been almost
impossible for man to have attained his present degree of
civilization, if it had not been given him by nature in such
abundance. Its uses have already been described in the arts of
brick-making, pottery, &c. Besides these three principal primitive
earths just described, there are seven others, having several
properties in common, yet each possessing its different and specific
properties, and evidently designed by nature for different purposes of
utility.
_Specific_, belonging to its particular species.
_Utility_, usefulness.
What is a Volcano?
An opening in the surface of the earth, or in a mountain, from which
are ejected smoke, flames, stones, lava, &c. Beneath the outer crust
of the earth inflammable materials appear to exist, which different
causes excite into combustion. Volcanoes are supposed to owe their
origin to the metals and minerals which form the basis of earths and
alkalies; and which, when ignited, expand,--shake the rocky
foundations,--and sometimes, bursting through, produce all the
destructive effects of earthquakes. They break forth under the sea, as
well as the land, and throw up mountains which rise above the level of
the water. During an eruption of Vesuvius, A.D. 79, three cities,
Herculaneum, Pompeii, and Stabiæ, were overwhelmed, and lay buried
beneath the matter ejected from the volcano until within a few years,
when excavations were made and many relics discovered;--streets,
houses, papyri, (manuscripts,) grain, fruit, bread, medicines, &c.
&c., all in a remarkable state of preservation, have been found just
as they were left by the terrified inhabitants at the time of the
eruption!
_Eruption_, an issuing or breaking forth with violence.
_Ejected_, thrown out.
Are there many Volcanoes?
There are upwards of two hundred volcanoes upon the globe; more than
one half of them are in America and Oceanica The most noted volcanoes
in America are Cotopaxi (the highest in the world), near Quito;
Popocatapetl, in Mexico; Cosiguina, and the Water Volcano, in
Guatemala. In France, Spain, Portugal, and many other countries, there
are districts which show the former existence of volcanoes, which have
long been extinct; near Naples, in an area of two hundred square
miles, there are sixty craters, some of them larger than Vesuvius; in
one of these, the town of Cumea has stood for three thousand years.
What can you say of new islands formed by Volcanic Agency?
Many examples of new islands rising out of the sea by volcanic action
are on record. Some of them are permanent, but others, after a time,
disappear. Teneriffe, Iceland, Sicily, St. Helena; part of Sumatra,
Java, Japan; and the Sandwich Islands, seem to have been upheaved by
volcanic agency; Hawaii, the largest of the last-named group, contains
an area of four thousand square miles, and rises eighteen thousand
feet above the ocean.
What are Earthquakes?
Shakings or vibrations of the ground; sometimes accompanied by rents,
and rockings or heavings of the surface, so as to overthrow buildings,
and swallow up towns and large tracts of country. They are attended
with a terrible subterranean noise, like thunder, and sometimes with
an eruption of fire or water, or else of smoke or winds.
_Subterranean_, underground.
What is supposed to cause them?
An electrical action between the atmosphere and some deep sub-strata;
or the sudden formation of gaseous matter beneath the surface of the
earth by internal volcanic fires. Many hot countries, where much
electrical disturbance takes place, are very subject to them:
earthquakes almost always precede volcanic eruptions; an open volcano,
also, probably diminishes the force of earthquakes, by the vent which
it affords. Earthquakes, at different times, have been productive of
the most terrific effects: towns and cities have been swallowed up,
and thousands of people destroyed by them. The island of Jamaica is
remarkable for the earthquakes which frequently happen there.
_Precede_, to go before.
_Vent_, opening.
_Terrific_, full of terror, dreadful.
Where is Jamaica situated?
In the West Indies,--a large group of fertile islands which lie
between North and South America. Jamaica is the principal one of those
which belong to the English.