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TABLE OF

OF CONTENTS.

PAGE

5

9

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DEDICATION to Swarthmore College

Introductory Note.

Explanation of some Symbols and Abbreviations employed

:

Remarks to the Student

Various Geometrical Problems in “Triangles, Quadrilaterals, and Par-

allels,” analyzed by Geometry, 64 in number

Geometrical Problems involving Properties of “the Circle," analyzed

by Geometry, 33 in number .

Theorem and Problem proposed by Francis Miller

Problem to illustrate the Mode of "Discussing a Problem”

Construction of Algebraic Equations of one unknown quantity of the

First Power, in which each letter represents a right line

Construction of Algebraic Equations of the Second Degree

Problems analyzed by Algebra, and constructed and demonstrated by

Geometry

Problems analyzed by the Differential Calculus, and constructed and

demonstrated by Geometry.

Problems in relation to Areas and the Division of Surfaces
Demonstration of some Theorems

66 Theorem of Pappus”
Theorem proposed in Ladies' Diary for 1735–6
This Theorem extended and applied
The same Theorem further applied. (X.)
Three Theorems believed to be original
A Theorem and Singular Property deducible from these
A Problem in Tree-Planting deduced from Theorem X. .

Problem in Tree-Planting, proposed in The Agriculturist
An Attempt at simple Illustrations of some Principles and Problems in

the Differential and Integral Calculus .

Finding the Differential of a Simple Function

Finding the Integral of a Simple Function

The Differential Co-efficient

To find the Areas of Plane Figures by the Calculus

To find the Solidity of the Cylinder, Cone, Paraboloid, and Sphere

by the Calculus

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Some Elementary Problems in Analytical Geometry

240

The Equation of a Point .

240

The Equation of a Straight Line

243

To construct an Algebraic Equation of two unknown quantities of

the First Power

243

Having given two Equations of two unknown quantities of the

First Power, to find the values of the unknown quantities by

Construction

250

To construct the Circle from its Equation

252

Section on Curves, showing the manner of constructing several of

them, and some of their prominent Properties

253

The Parabola.--To determine Points in the Parabola geometrically,

and deduce its Equation

253

To find the Axis, Focus, Directrix, Latus Rectum, etc. of a given

Parabola by Construction

255

To construct a Parabola by Points from its Equation

256

The Ellipse.--To determine Points in the Ellipse geometrically,

and find its Equation

257

To find the Axes, Foci, Focal Tangents, Tangent, Normal, Sub-

tangent, etc. of a given Ellipse by Construction

258

To find the Area of an Ellipse by the Calculus

260

To construct the Ellipse by Points from its Equation

260

The Hyperbola.–To determine Points in the Hyperbola geomet-

rically, and find its Equation when referred to its Asymptotes 262

Having the Equation of the Hyperbola referred to its Asymptotes,

to determine its Equation when referred to its Axes

264

To construct the Hyperbola from its Equation by means of Points . 265

To construct the Conchoid of Nicomedes

270

To construct the Cissoid of Diocles .

271

To construct the Quadratrix of Dinostratus

272

To construct the Logarithmic Curve

274

To construct the Spiral of Archimedes

276

To construct the Lemniscate from its Equation

277

Table of Square Roots of Numbers from 1 to 200, to facilitate the Con-

struction of Curves by Points from their Equations

279

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INTRODUCTORY NOTE.

In an engagement of nearly forty years' duration in teaching Mathematics, first in the boarding-schools of Fair Hill, Maryland, and Westtown, Pennsylvania, and afterwards in a boarding-school of my own, for boys and young men, at Alexandria, Virginia, I became convinced that the analytic or algebraic method of Descartes, Delambre, and Laplace, while it is a most efficient instrument in the hands of a mathematician, is not so well adapted as the geometric or Greek method, to impart to the student a knowledge of mathematical principles, or to inspire such student with an affection and taste for the science.

The mind of the young is less capable than that of an older person of abstract thought, and it needs assistance to the concentration of its ideas, such as is afforded by a mathematical diagram; and with this aid continued for some time, the faculties of perception and conception become cultivated and strengthened, till the mind of the student can readily grasp, without a diagram, a problem of considerable intricacy, and be able to apply to it Descartes' method efficiently

So entirely has the analytic method taken the place of the geometric in our prominent schools and colleges, that no work on pure Geometrical Analysis has, to my knowledge, ever been published in this country.

Thomas Simpson, F.R.S., and Professor of Mathematics in the Royal Academy of Woolwich, England, in his “Select Exercises for Young Proficients in the Mathematics," which was published in London in 1752, gave a number of geometrical problems, with the method of constructing them.

And, in a treatise on Geometry, by the same valued author, published in London in 1760, the fifth and sixth books are entirely devoted to the Construction and Demonstration of Geometrical Problems; and nearly fifty problems, of great variety, and some of them of much elegance and beauty, are constructed and demonstrated at the end of the volume.

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To his Algebra, also, which was published in England about the same time, and reprinted in Philadelphia, by Mathew Carey, in 1809, “from the Eigbth London Edition," Thomas Simpson added an “Appendix, containing the Construction of Geometrical Problems, with the Manner of resolving them numerically." This work was of very great value to the mathematical student, and of much service to my revered preceptor, John Gummere, in the preparation of his admirable treatise on Surveying, which was published a few years after Carey's edition of Simpson's Algebra was issued.

But in all these works, including the problems in Gummere's Surveying, the mode of construction was arbitrarily given, without the least clue to the line of thought that had led to it; and the thoughtful student would naturally inquire, and even wonder, in a problem like the seventy-sixth or seventy-seventh of the Appendix to Simpson's Algebra (Problems six and eight in “ Algebraic Analysis” in this book), how the author ever came to think of so complicated a method; and he would feel discouraged, in view of its complexity, from an apprehension that his own mind would never be endowed with a penetration sufficient to accomplish a result of such intricacy and depth.

Whereas, had the problems been analyzed, and the student shown that it was all done by taking one step at a time, and that an easy one, --gradually acquiring a knowledge of what we do not know by means of what we do know, which Doctor Johnson says is the only way it can be done, he would have felt increased confidence in his own powers, and been prepared to make an effort himselfwhich is a great point--in a similar direction.

In 1821, Professor John Leslie, of Edinburgh College, published, in Edinburgh, a very valuable treatise on “Geometrical Analysis, and Geometry of Curve Lines.” The “

The “ Geometrical Analysis” had been previously published, annexed to his " Elements of Geometry,' and it greatly “conspired to advance the study of Geometry, by reviving the fine models bequeathed by the Greeks.” As has been said with great truth of this work of Professor Leslie, “the study of such a digest, appears admirably fitted to improve the intellect, by training it to habits of precision, arrangement, and close investigation. The spirit of Geometrical Analysis may be carried, with the happiest effect, into the domains of Inductive Philosophy, which are to be explored by a similar procedure."

But, about the time of the publication of this work of Professor Leslie, the algebraic method of Descartes and Leibnitz came rapidly

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