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STUDIES serve for delight, for ornament, and for ability. Their chief use for delight, is in privateness and retiring;
for ornament, is in discourse; and for ability, is in the judgment and disposition of business : for expert men
Presented by the thon
LUDGATE HILL, E. C.
In bringing our Fourth Volume to a close, we heartily thank all our Subscribers for their steady and unwearied support. The letters of encouragement and of commendation which we have received during the past six months, have been more numerous and more gratifying than ever. We have endeavoured to show our sense of these favours, by labɔuring more earnestly to impart solid and useful instruction in various important branches of learning; we have, in fact, considered that we were entrusted by our readers with the responsible task of their education, and we rave aimed at fulfilling our duties to their satisfaction. We have given a concise and popular summary of the leading facts in several branches of Natural Philosophy, as may be seen by consulting the Index; but many highly useful and interesting departments are soon to follow in their order; these are Caloric and Optics, or the doctrines of Heat and Light, including some of their most interesting applications, as the Steam Engine, the Telescope and Microscope, Daguerreotype and Photography; Magnetism and Electricity, including the nature of the Telegraph, the Electrotype, and other useful applications; and, as soon as possible, Astronomy, which is much in demand.
Chemistry has also been treated in a highly popular manner, and has converted a great number of our Subscribers into practical Students of that art. The elegant languages of ancient Greece and of modern Rome have also occupied our pages, and have been expounded with great care by the authors of the Lessons on these branches of Literature; nor have we forgot our Students in French, as a “ Course of Readings” in that popular language is still appearing at convenient intervals. The Mathematics, including Algebra and Geometry, with Instrumental Arithmetic and Mathematical Illustrations, have also been progressing under our own care, and these branches will be still more vigorously pursued in our next Volume, where some of them, if possible, will be brought to a conclusion. Bookkeeping has already occupied a portion of our labours, and we shall conclude this branch in a few early Numbers, with the subject of Foreign Trade. The Lessons in Reading and Elocution will be rendered still more useful and attractive in our next Volume; but we cannot promise any new language till we have finished one or more of those now in hand ; the German, however, is very near a conclusion. We are preparing for Lessons in Mechanical Drawing, and in various other branches which have been unavoidably, postponed, on account of the great demand for those which we have given, and which we are now carrying on. In closing these remarks, we can only say that we shall continue to place before our Readers, as we have always striven to do, those subjects which are the most irr demand, and which are calculated to do “ the greatest possible good to the greatest possible number.”
LESSONS IN ALGEBRA.
LESSONS IN GEOGRAPHY.
Map of France, with the Railways, and Divisions
into Provinces and Departments; Map of
Turkey in Europe, with Greece and the Ionian
Islands; and Division into Provinces and
Islands, Map of the Austrian Empire, with
Divisions into Provinces and Population;
Map of Russia in Europe, with Divisions into
X. Cotton Book; Purchases; Sales; Profits 176
XLVI. Results of the Agency of Man, by Agriculture,
XII. XIII. The Ledger ; Posting; Balancing; Index to XLVIII. Relative Position of Rocks in their vertical order 231
XLIX. Rocks of Recent Formation; Rocks in course
III. Zinc; Manganese ; Facts for the Student, etc.. 37
XXIII. Lectures on Euclid, Book I. Props. XVI.,
VI. Application of the Pneumatic Trough
XXIV. Book I. Props. XIX., XX.; with Scholia, Corol-
laries, and Exercises
XXV. Props. XXI., XXII., XXIII; with Scholia,
XXVI. Props. XXIV., XXV., XXVI.; with Scholia
Corollaries, and Exercises ..
XXVII., XXVIII., XXIX; Props. XXVII., XXVIII;
XXV. Principle of the Blast Furnace; The Argand LXXIX. Observations on the Paradigm of a Compound
Verb; Inseparable Prefixes,..
XVII., XVIII. The Pronouns ; Personal; Reflective;
XXIII, Conjugation; Augment; Characteristic Let- XIV., XV. Capillary Attraction; its Effects; Laws of
the Ascent and Depression of Liquids in Capil-
lary Tubes, between Plates of Glass, in Siphons;
of Liquids in Contact with Solids, etc. 203, 213
XVI. Endosmose, Absorption, and Imbibition; Ab-
III. The Plane Scale and Protractor ; Principles of
spheric Pressure; Torricellian Experiment;
XVIII. The Atmosphere ; its Pressure ; the Barometer,
Cistern, Portable, and Siphon; Variations in
Apparatus for Increasing Sound; Effect of
XI., XII. The Articles; Declension of Nouns 159, 178
XXV. Echoes and Ringing Sounds; the Speaking and
192, 211, 232
Hearing Trumpets; Vibrations of Cords; the
Monochord; Nodes and Nodal Lines; Savart's
Toothed Wheel; the Siren; the Blowing
XXI. Use of the Preposition Per, and Exercises...... 356
Sound; Unison; Gamut; Diatonic Scale;
Intervals, Sharps and Flats; Harmony, Dis-
cord; Pulsation; Tuning Fork; Vibrations
Length of Notes; Absolute Length of Notes
LESSONS IN READING AND ELOCUTION.
I. Punctuation ; Characters employed
XXI. Of accidendal Flats and Sharps, and Rules
Note of Exclamation; Rules and Examples.. 285
III. The Comma; Rules and Examples
IV. The Semicolon; the Colon; the Parenthesis,
Crotchets, and Brackets; Rules, etc.
XXII. Minor Tunes ; Exercises ; Remarks on the Com-
IV. Description of the Skeleton Map of Africa, with
Table of Latitudes and Longitudes; Table of
the Length of Degrees in Different Latitudes 7
Inclined Plane, Atwood's Machine, Morin's
VI. Moral Excellence; Cyrus; Confucius ; Socrates ;
VIII. Hydrostatics; Properties of Liquids; Piesome-
1. Asymptotes to Curves; the Conchoid; the Conic
X. Bodies immersed in Liquids; Principle of
Sentences, 176. University of London, Nos. IV., V., and VI., 207,
centre; Specific Gravity; the Areometer ....
ON PHYSICS, OR NATURAL
OBJECT OF THE SCIENCE.
The object of physics, or natural philosophy, is the study of all in the air, and a great number of other bodies, to which the phenomena which material substances present, except those general appellation gas or aëriform fluid is applied. In gasos which relate to changes of internal composition; the latter the mobility of the molecules is still greater than in liquids; but come under the domain of chemistry. For example, selecting the special characteristic of gases is their unceasing tendency the metal iron as a subject of contemplation, we may study its to expand into a greater volume; a characteristic expressed by specific gravity, its degree of hardness, its property of weld- the term expansibility, and which will hereafter be demonstrated ing, of being drawn out into wire, and rolled or beaten into experimentally. The general term fuid is applied both to plates; all these phenomena depend upon the physical proper liquids and to gases. The greater number of simple bodies, ties of the metal, and the study of such phenomena comes under and many compound ones, are capable of presenting themselves the domain of physics, or natural philosophy, sometimes called successively under the three forms of solid, liquid, and gaseous, mechanical philosophy. But iron is endowed with another according to the variations of temperature to which they are set of qualities. It is capable of being dissolved in certain exposed. Of this successive change, water affords a well-known acids, and rendered invisible as iron, although its presence may example. Hereafter, when we farther advance into the regions be recognised by various tests. All this department of study of natural philosophy, it will be found that the three states of belongs to chemistry;
solid, liquid and gaseous, depend chiefly on variations of We have stated that matter (or material bodies) admits of molecular attraction and repulsion. being studied under two aspects : but what is matter? It is On Physical Phenomena.-Every change which the state of a necessary to arrive at some understanding as to this question body may undergo without involving alteration of composition before proceeding farther. Perhaps the best definition of mat- is a physical phenomenon. The falling of a body, the sound ter is comprehended in the expression, whatever falls or is produced by such falling, the freezing of water, all are physical capable of falling under the immediate cognisance of the phenomena. senses. At this time, there are sixty-three known elementary, or to designate the constant relation which exists between any
Laws and Physical Theories. The term physical law is applied simple bodies; that is to say, bodies out of which chemical particular phenomenon and its cause. For example, in demon. analysis has not succeeded in extracting more than one species Atrating the fact that a given volume of gas becomes one-half, of matter. Nevertheless the number sixty-three is by no one-third, one-fourth, &c., its original size, according as it is means to be regarded as the permanent representative of simple exposed to a degree of pressure, twice, three times, &c., we illusbodies. Possibly their number may hereafter be increased or trate the well-known physical law which is expressed by saydiminished, according as new simple bodies may be discovered, ing that the volumes of gases are in an inverse ratio to the or those with which chemists are at present acquainted may pressures under which they eiist. A physical theory is the colbe proved to be made up of simple constituents.
lection of laws relating to the same class of phenomena. Thus Bodies, Atoms, Molecules.-Every definite or limited amount we speak of the theory of light, the theory of electricity. of matter is termed a body or mass, and the properties of such Nevertheless this expression also applies, though in a more bodies or masses show that the matter of which they are com- restricted sense, to the explication of certain particular phenoposed is not continuous, but is made up of elements, as it were, mena. In this latter sense, we speak of the theory of San, the infinitely small; so small that they are incapable of physical theory of mirage, &c. or mechanical division, and not in actual contact, but in near Physical Agents.-As causes of the phenomena which bodies proximity; the distances between them being maintained by present, philosophers admit the existence of physical agents or reciprocal repulsions, known under the name of molecular natural forces, by the operation of which all matter is governed. forces. These minute elements of bodies are termed atoms, These agents are universal attraction, caloric or heat, light, and groups of atoms are termed molecules,-of which latter, a magnetism and electricity. Mere physical agents only manifest body or mass is only an aggregated collection.
themselves to us by their effects, their ultimate nature being Mass.—The term mass of a body is applied to the amount of completely unknown. In the present state of science, the matter which it contains. The absolute mass of a body cannot question still remains undetermined, whether the physical be determined, but its relative mass, considered with regard agents are to be regarded as properties inherent in matter, or to the mass of some other body taken as unity, can be readily whether they are in themselves subtle material bodies, impalarrived at.
pable, pervading all nature, and the effects of which are the Physical Conditions or states in which Bodies exist.—These result of movements impressed upon their mass. The latter states are three, each being well characterized and readily dis- hypothesis is that most generally admitted ; but being admittinguishable from the others. 1. The solid state. This condition ted, next follows the important question,—"Are these kinds of is manifested at ordinary temperatures by wood, stone, and matter distinct amongst themselves, or are we to refer them to metals. It is characterized by an entire adherence of mole. one and the same source?" This latter opinion appears to gain cules amongst themselves, so that they only admit of separa- ascendency in proportion as the boundaries of natural philosotion by the exercise of a certain degree of force, varying for phy, become expanded. Under the assumption that the phydifferent solids, and for the same under different circumstances. sical agents are subtle forms of matter, devoid of all appreciIt is a direct consequence of this molecular adherence, that able weight when tested by balances of the highest sensibility, Bolid bodies retain their original forms. 2. The liquid state. they have been termed imponderable fluids ; hence arises the of which we are furnished with examples in water, alcohol, distinction between ponderable matter, or matter properly and oils. The distinctive character of liquids is an adherence 80 called, and imponderable matter, or imponderable physical of so feeble a degree between their molecules, that the latter agents. slide upon and pass each other with extreme facility, in conse
ON THE GENBRAL PROPERTIES OF BODIES. quence of which it results that liquid bodies do not affect any external form of their own, but invariably assume that of the Different kinds of Properties.
By the term properties of bodies containing vessel. 3. The gaseous state. Or this we have examples or of matter is understood, the different methods by which they VOL. IV.