The economy of the eyes : precepts for the improvement and preservation of the sight : plain rules which will enable all to judge exactly when, and what spectacles are best calculated for their eyes : observations on opera glasses and theatres, and an account of the pancratic magnifier, for double stars, and day telescopes

Front matter

LOWER HALL.

BOSTON PUBLIC LIBRARY.

One volume at a time can be had in home use from either Branch or from the Lower Hall of the Central Library, and at the same time one from the Bates Hall of the Central Library; and this volume must always be returned at this Branch, with the applicant's library card, within such hours as the rules prescribe.

Part II. How To Choose And How To Use

TELESCOPES,

OF ALL KINDS AND ALL SIZES, AND FOR ALL PURPOSES,

The Illuminating and Magnifying Powers and Prices of Newtonian, Gregorian, Cassegranian, and Herschelian Reflectors, and Galilean, Huygenian, and Achromatic Telescopes, of from 3 Inches to 7 Feet Focus, being Calculated and Described in Plain Terms which all Persons

., may easily understand To which will be added, An Appendix from the Writings of Sir Isaac Newton, Sir William Herschel, &c. and Original Communications from Eminent Practical Opticians of the present time, on the Construction and Use of Telescopes.

LONDON : PRINTED BY J. MOYES, GREVILLE STREET.

CONTENTS,

PAGE

Preface, to be read after the Work- • • 1

Spectacles for the poor • 10

Chap. I. On Reading Glasses for Persons whose Eyes are impaired by Age; and Single Eye Glasses for the Short-sighted * 12

II. Spectacles with Plain Glasses* • 18

III. Cases of Persons who could not read in Spectacles 20 and 34

IV. Hand Spectacles 15 and 21

V. Symptoms of the Eyes requiring Spectacles to read with • • • ♦ 23

VI. Of Preservers • • 29

VII. Table of the Focal Length of the Magnifying Glasses required

at various Ages • • 33

The time that the First Glasses of 36 Inches focus will assist the Sight sufficiently 37

VIII. When to change the First Spectacles 38

The Premature Use of Spectacles, how pernicious to the Sight 32

IX. My Grandmother's Spectacles* • 40 Spectacles for Gourmands •••• 41

X. Hints to Persons choosing Spectacles 44

Divided Spectacle Glasses 48

Plan for Preserving the Sight • • 51

IV CONTENTS.

PAGE

Chap. XL Hints to Persons beginning to wear Spectacles; and of Reading-

Lamps and Candlesticks 57

Case of Dimness of Sight from Over-exercise of the Eve 67

Of the Pole Star • •* 67

Of the Double Ring of Saturn ••••••• 69

Contents of the Second Part of the Economy or the Eyes 71

Magnifiers for Artists • • • * 73

Concaves for reducing Miniatures • • • • 77

Nervous Dimness of Sio;ht • • • • 78

Ointment for the Eye-lids 79

XII. Precepts for Improving and Preserving the Sight • • • • • 81

The Circumspector • • ° 84 and 200

Sight-Strengtheners for Painters, &c. • • 85

Double Rising Desk 87

Reading Candlestick • • » 90

Green or Coloured Glasses • • 91

To keep Glasses perfectly clean •••••• 93

XIII. Glasses for Short-sighted Persons 94

History of the Author's Case of Spectacles 95

Invisible Opera Glasses 103

The Disadvantages and the Advantages of being Short-sighted 104

XIV. Spectacle Frames ♦•• 107

Silver Frames • • ••• •• 107

Tortoise-shell Do. 107

Blued Steel Do. 107

The Length of the Bridge 109

Mean Distance between the Eyes • • • • 109

Width of a common Spectacle Frame » • 111

How many Tears shed Daily Ill

CONTENTS. V

PAGE

Proper Shape for the Openings which

hold the Glasses 112

Length of the First Joint 113

Prices of Spectacles 114

Chap. XV. Of the Quality or Spectacle Glasses, and how to measure their Focal Length 115

XVI. ' Pebbles 117

The Expense of the Best Glasses is a

Groat per Annum 121

XVII. On the various Degrees of the Perfection of the Eye and P^ar 121

The Gritty Chord 121

The Ocular Harpsichord 122

Beef and Cabbage, the music of 123

Good Sense and Good Senses 124

Perfect Senses 127

Bad Senses 128

Advantages of Insensibility 129

Portraits of Double Stars 133

Day Telescopes, how to use with perfect Vision and with effective Power 136

a Geminorum seen double 137

£ Bobtis do. 138

Hints to Observers of Double Stars • • • 139

Hints to Dumpy Fanciers 1 40

Newtonian Diagonal Eye-piece • 146

Advice to Buyers of Telescopes 157

XVIII. Opera Glasses 161

How to adjust an Opera Glass for various Eyes, and for various Ages, and Objects at different distances 163

How to hold an Opera Glass • 163

Field of View in an Opera Glass « • • • 167

The Grand Dandy Opera Glass • • • • • 168

Vi CONTENTS.

PAfeE

The Stops- 168

The Opening of the Pupil 172

Revolving Eye-head • 173

French Operas • • • * 173

English do. 174

Magnifying Power, how to vary 174

To see if any of the Object Glass is

cutoff 175

Diameter of Eye-glass • 176

Do. Eye-head 177

Average Distance the common Eye can see distinctly the Expression of the

Countenance 178

Average Distance between Spectators

and Performers ••••• 178

Requisite Magnifying Power to enable a Person to see as distinctly as if they were within 15 feet of the Stage* • • • 178 The Bell Opera with one sliding Tube

the best 178

Of Operas which have many Tubes • • - • 178 Operas for the extremely Short-sighted . 180

Operas that have no focus ** 181

Invisible Opera Glasses • • • - 103 and 182

Opera for a Picture Gallery 183

Opera for sweeping for a Comet 183

The Ouranologia ♦ • 183

Single Object Glasses 185

Concave Eye-glasses for varying the

Magnifying Power 1 86

To ascertain the relative Powers of Eye- Glasses ; • 187

Imperfections in Opera Glasses, to discover 189

Prices of Opera Glasses * 1 89

Cautions in trying Opera Glasses • • • • 1 89

CONTENTS. Vll

PAGE

Comparisons of Single and Double Object Glasses 1 92

To measure the Magnifying Powers • • 197

Diagonal Opera Glass 200

Circumspector 84 and 200

Chap. XIX. Theatres 204

Distance from the Curtain to the Boxes

at the English Opera House 204

Ditto at Drury Lane 204

Ditto at Covent Garden 204

Of the Extension of the Voice 206

Mr. Arnold's Theatre 209

Mr. Garrick's > 209

Account of the Expense of Building the

present Drury Lane Theatre 209 — 211 Number of Seats, &c. in the English

Opera House 212

Ditto, Drury Lane 212

Ditto, Covent Garden 212

Ditto, Haymarket 212

Ditto, the Words marked as they ought to be sung 220

RESPECTING SPECTACLES.

No. I. Rules for Choosing Spectacles, by

George Adams, Optician 221

II. George Adams on Short-sightedness 224

III. Of Optometers 225

IV. Dr. Smith's Rules for Choosing Spec-

tacles 226

V. Indistinctness in Old Eyes how caused

and how cured, by Dr. Jurin • • • • 22&

Vlll DESCRIPTION OF PLATES, &C.

PAGE

No. VI. Curious Experiment 231

VII. Dr. Wells on the Changes which the Vision of Short-sighted Persons undergoes from Age 232

VIII. Mr. Ware's Observations on the Near

and Distant Sight of different Persons 235 IX. Appendix to Mr. Ware's Paper, by

Sir Charles Blagden 240

X. Sir William Herschel on the Apertures of the Pupil of the Eye 243

Explanation of the Plate fronting the Title.

Fig. I. Is the Spectacle front recommended for Eyes in general ; the distance between the centres of the openings which hold the Glasses being 2\ inches, i. e. the average distance between the centres of the Eyes.

Fig. II. Is a portrait of the Pupil of the Eye when in a state of expansion. See Chapter XII. page 81, and No. X. of the Appendix.

Fig. III. The Pupil in its most contracted state. See page 81, &c.

Fig. IV. Convenient double Folding Hand Spectacles, See page 22.

Fig. V. A Preserver, or the Firstm Sight for Long Sighted Eyes, i. e. a Convex lens of 36 inches focus cut in half i — to shew its form, &c. the thickness of it at the middle and at the margin of it. See page 29.

Fig. VI. The 8th Sight, for Long Sighted Eyes — or 12 Inches focus.

Fig. VII. No. 1 Concave, or the First Sight for Short Sighted Persons. See Chapter XIII. page 94.

Fig. VIII. No. 12 Concave, or the 12th Sight for Short Sighted Persons.

The Plate of the Pancratic Eye-Tube and Double Stars to face page 1 30.

Preface

TO BE READ AFTER THE WORK.

Now, friendly Reader, before I take leave of You — after — Your deliberate perusal of this Volume, — if You vote that my labour has been lost, or has afforded you so little pleasure, that You begin to think You would rather have your Seven Shillings in your pocket again, than this first part of " the Economy of the Eyes" under your Chin, — allow me to suggest, that You ought to Lend it to every body You know — to prevent others being decoyed, as in such case You will suppose you have been — to buy a Book which is not worth reading.

But if it so happen that fortunately for the Writer, You think you have derived Amusement or Instruction from his Work, — if You are so good as to wish to be grateful for the Information which it has given you — Lend it not — to one of those prudent folks who are in the habit of borrowing your new Books, and so contrive to become wise at your expense, — but do the Author the favour to recommend all your Friends to purchase it.

Introduction

GENERAL OBSERVATIONS ON SPECTACLES.

Without Spectacles'* all the other working tools, of most Artists, soon after their 40th year, would be almost useless.

At that precious period of Life, when Genius begins to wait upon Judgment/)- the persever* ing Student would no longer be able to enjoy the fruits of the labours of his Predecessors, or to preserve the produce of his own for the benefit of Posterity.

* " Were there no other use of Optics, than the invention of Spectacles for the help of defective Eyes, I should think the advantage which mankind receives thereby, inferior to no other benefit whatever, not absolutely requisite to support Life." — Molyneux's Optics.

f " The exact time when years have ripened the Judgment, without diminishing the Imagination, by good critics is held to be punctually at Forty"— See Martin Scriblerus on the Dunciad} p. 55.

The accomplished Artist, almost as soon as he acquires his Art, would be incapable of pursuing it, — the seeds of perfection which he has been industriously cultivating during the First period of Life, would very soon after cease to be productive, and, but for the Eyeinvigorating Art of the Optician, his latter days would be melancholy and forlorn.

It is hoped that by a little attention to the following pages, that All who can hear,# may be enabled to procure precisely such Glasses as are most proper for them.

Every body is in want of such Information, because Nobody has given it, — therefore, I have endeavoured to render it as easily attainable, as it is universally desirable, by communicating it in such plain terms that Every body may understand.

The choice of Spectacles is one of those acts which cannot be properly performed by proxy — the Sight cannot be perfectly suited, unless

" Every Eye negociate for itself."

* It is presumed, that the majority of the purchasers of this Work, cannot See ! till they have learned how by the instructions herein given.

This is so absolutely true, that not only One Person cannot choose for Another — but One Eye has often very little notion what Glass will be best even for its own Brother, so extremely does the Left Eye occasionally differ from the Right.

No faculty of man varies more in its nature, or is susceptible of so high a degree of Improvement and Refinement by Art, as the Sense of Sight. The highest degrees of its discriminating power are acquired slowly and imperceptibly.

From organic imperfection and neglect of cultivation^ many People pass through Life who (it may be said, comparatively,) never See — i. e. whose Eyes never have the faculty of accurately appreciating either Form — or Colour : — to very few indeed is it given to perfectly perceive and portray both.

There cannot be a more evident proof of the

* " Every person acquainted with Optics and the nature of vision, knows that what is generally comprehended under the term Seeing, is a complex operation; an art acquired by degrees, in which judgment and imagination are concerneda together with simple perception." — Crisp on Vision, 8vo. 1796, p. 106.

general defect in people's Sight — than the general acceptance of capricious and unreasonable Fashions, which appear to be prevalent, in proportion that they are in direct opposition to all the principles of good taste, and which to a fine Eye, are frequently frightful, and absolutely painful to behold.

From the different modes of colouring of different Artists, I suppose that the Eyes of no two Painters feel exactly the same impression of colours, — and objects, appear of different Colours accordingly as they are illuminated with different Lights.

" The Mole's dim curtain, and the Lynx's beam,'*

Pope. do not differ more extremely than does the Sight of different persons — and of the same persons at different Ages.

The peculiar conformation of the Eyes, differs quite as much in different persons, as the construction of their Noses ; — it is just as impossible to guess exactly what Spectacles will best suit the Sight of another Person, as it is to tell what Tunes are most delightful to his Ear, — or what Tastes are most delicious to his Tongue.

Nothing can be more erroneous than the common notion, that there is an invariable Rule, that a certain form of Glass is calculated for a certain Age. No Rule has more exceptions : — but this Vulgar Error has been productive of great and irremediable Injury to the Eyes of Thousands !

Hence, the grand desideratum, is to instruct people how to choose wisely for Themselves — which, I hope, even those who are totally unacquainted with the subject may do with the most perfect ease and accuracy, by the help of this Treatise, which is not published for the purpose of recommending some particular Oculist — or of persuading the reader that the simplest of all Optical instruments, spherical Spectacle Glasses, can only be purchased of One Optician: — is not a collection of crude conceits, — but is a plain impartial statement of all the Facts I have accumulated during my consideration of the subject for 30 years past — in which I have

" Nought extenuated, nor set down aught in malice." My Motto, friendly Reader, is

" Truth, tempered by Good Humour."

' u Men must be taught as if you taught them not, And things unknown propos'd as things forgot. Without Good-Breeding, Truth is disapproved ; That only, makes superior sense belov'd."

Essay on Criticism.

I do not think it is my business — I am sure it is not my Pleasure, to register the various pretended improvements in Spectacles which have from time to time been proposed to the Public, — such as the Sympathetic Pebbles — which u as the Sight alters, they will alter also to the Sight, by which one pair will last the wearer for Life," &c. &c. &c. ! ! ! This would be irksome to the Writer, and useless to the Reader. — I shall only mention the most remarkable.

In 1785, Mr. B. Martin published a pamphlet recommending what he called

" VISUAL GLASSES,"

the use of which, he assures us, would be " productive of peculiar advantages," — they might be — but, by Mr. Adam's account, not to the gentlefolk who bought them.

" The desire men have to increase their

Business, and extend their Fame, has, in many instances, been the origin of alterations and inventions, — injurious to Science and detrimental to the Public.

u To this we may, with propriety, impute the invention of Visual Spectacles. But the good sense of the world, which always, in the long run, justly appreciates the value of every invention, now leaves Visual Spectacles to the neglect they merit." — G.Adam's Essay on Vision, 8vo. 1792, p. 113.

I beg to be excused saying more, than that 1 do not think that any of the Spectacle Glasses which have come before my Eye, have any superiority over the Common Spherical Lenses now in general use.

In instituting Experiments for ascertaining the distinctness and brightness of Spectacle Glasses — be extremely careful, that the Glass is not only of exactly the same quality, but also of exactly the same Focal length — or any attempt at comparison will be useless.

If one of the Glasses be only of a very little shorter focus than the other — objects will always make a very different, and sometimes a much stronger impression on the Eye.

i

To measure the Focal Length of Spectacle Glasses, see Chapter xv.

To give my Readers all the satisfaction in my power, — I have added an Appendix — which contains sufficient corroboration of what I have asserted on certain important points, — because — by the time Persons want Spectacles, they have generally become wise " in their own conceit," — and have picked up a parcel of silly prejudices concerning them, which unless completely counteracted, and rectified by the invariable standard of irresistible Truth, — will prevent their deriving that benefit from this publication, which the Author heartily wishes that they should receive to the utmost extent.

I have given Rules for the choice of Glasses as relates to their degrees of Magnifying,— and have also pointed out those criterions by which All may judge if the Glasses are good — and of the right focus — and readily discover those imperfections in them which are so common, and so injurious to the Eyes.#

* See Chapter xvii. " Of the Quality of Spectacle G lasses"* and the Note at the foot of page 40.

To effectually eradicate erroneous opinions, and to establish the Truth beyond all doubt, I know is no easy task — therefore, I have given an Appendix of Quotations from the best Authors on the subject — the correctness of whose Judgment has been established by Experiment, and has been pronounced indubitable, by universal acceptance — i. e. from the Writings of Dr. Smith; — Dr. Jurin; — Dr^ Porterfield ; — Dr. Blagden ; — Dr. Wells ; — Dr. Herschell; — Mr. G. Adams, the Optician; — the late Mr. Ware, the Oculist ; — and Mr. Stevenson, the Oculist; — and for many valuable facts, I am indebted to that experienced Optician, Mr. Samuel Pierce, who was upwards of Thirty Years with Mr. Jesse

Ramsden.

There could not be a more useful Charity — than that of providing proper

SPECTACLES FOR THE POOR.

The Best Glasses, set in Single- Jointed Steel Frames, may be purchased wholesale at the rate of 18s. per dozen Pairs; — if a Singlejointed frame is fastened round the head with a Riband, it may be kept on, almost as steadily and comfortably as a Double-Jointed Frame.

For the small sum of 18 Pence the Benevolent may enjoy the gratifying reflection of giving an industrious Workman the power of long continuing his labour with undiminished Ability, and of earning a subsistence till extreme Old Age.

In no way — can so much Good be done ivith so little Money I

The greatest part of the Disorders of the Eyes of Poor People who are upwards of 45 years of Age, are occasioned by their straining their Sight for want of Spectacles, — or by looking through Bad Glasses, — or those of a Focus not suitable to their Eyes : — I hope when this is considered by the Overseers of the Poor, — The District Societies for Bettering the Condition of the Poor, and the Patrons of The Eye Infirmaries, that they will make the distribution of Spectacles a part of their Bounty*

Chapter I

For Persons ivhose Eyes are impaired by Age — and Single Eye-Glasses for the Short- Sighted.

When would-be-thought-young Persons, first feel the necessity of giving their Eyes Optical assistance, they are, nevertheless, shy of mounting Spectacles, which they seem to consider an inconvenient manner of advertising their Age upon their Nose — not reflecting that they are worn by many persons who have not seen half their years, but who being Short Sighted, are obliged to walk about in Spectacles, or forego the sight of " the Human Face Divine. "

However, they suppose that Spectacles are such unequivocal evidence of Age and Infirmity— that they desire to dispense with exhibiting them as long as possible — therefore, they purchase "a Reading Glass," and habitually put it up to One and the same Eye, leaving the other involuntarily to wander; — after a few years, the sight of the Idle Eye becomes of a different focus to that which has been employed with the Glass — and is often irreparably impaired.

" These puerile propensities, give rise to a variety.of artifices, by which each individual endeavours to hide from himself and others, what no artifice can conceal, and which every one can discover, in all but himself ; — these endeavours often contribute to hasten the Evils they are meant to conceal. Opticians have daily experience of the truth of this Observation, and in no instance more so than in the preference given by many to Reading-Glasses , (under whatever pretext it may be covered) merely because they think that the decay of their Sight, and their advances in age, are less conspicuous by using a Reading-Glass, than Spectacles: but the Eyes in endeavouring to See with a Reading-Glass are considerably strained, and in a short time much fatigued: and there is another objection to the use of Reading-Glasses, which arises from the unsteadiness of the hand, and the motion of the head, which occasion a perpetual motion of the Glasses, for the Eye endeavours to conform itself to each change, and this tender organ is thereby kept in continual agitation : to these evils we may add the dazzling glare and irregular reflexion from the surface of the Glass, which so weakens the Eyes, that those who accustom themselves to a Reading-Glass, are in a short time obliged to take to Spectacles, and to use them much older than they otherwise would have done. " — Mr. George Adams on Vision, 8vo. 1789, p. 115.

When persons who have long patronized One Eye, and slighted the Other, take to Spectacles, they will (generally) require Glasses of a different focus for each Eye.

When You go to an Optician's to choose Spectacles, the first thing to attend to, is to look at a Book with each eye alternately, — and carefully ascertain, if You see equally well, with both Eyes, with the same Glass, at exactly the same distance.

Inequality of the focus of the Eyes, is much more common than is generally supposed, as Watchmakers, Engravers, and most Artists who work with a Magnifier, will tell you ; they generally work with One and the same Eye — with which, they can see much better than with the other.

After a certain Age, the relative sharpness of the sight of the Eyes, varies as much as does the quickness of the Ears — the Senses of Hearing, — and of Seeing, begin to fail about the same time ; — there are few people past 40 who cannot hear better with One Ear, than they can with the Other.

The Eye least used, soon becomes weak, and in the course of a little time almost useless.— This fact, is so little known, that I have frequently heard persons who up to the age of 40 have worked their Right Eye — and finding it begin to fail, say, they must begin to teach their Left Eye to See — however, as I told them, they found on trial, that the Eye which had been Idle, was much more impaired than that which had been active.

" By ceaseless action all that is, subsists."

Cowper.

Spectacles are always preferable, because

both Eyes* by being kept in action, are kept

in Health — Vision is brighter and easier,

and the labour of each Eye is considerably

lessened.

* To ascertain whether an Object seen with Both Eyes, appears brighter or larger, than when seen with One Eye

ON READING GLASSES.

As the Eyes of Persons who have either a very Long. or a very Short sight, are useless without Optical assistance — they should have Double Folding Spectacles slung round their neck ; (See Chapter IV. and Figure IV. in the Plate fronting the Title); or, if they will have a Single Eye-Glass — let them take care to use it without partiality — and put it to Each Eye alternately.

A Single Glass, set ir^ a smart Ring, is often used by Trinket-fanciers merely for Fashion's sake, by folks who have not the least defect in their Sight, — and are not aware of the mischievous consequences of such irrita-

only, Dr. Jurin made several experiments, which are too long to insert more than the results of them.

" This difference was most conspicous, when in making the experiment by candle-light, the book was at such a distance from the candles as that there was scarce light enough to read with both eyes ; when the column which was seen by One Eye only, was not at all legible; but I could read with both; though with some difficulty. — See Dr. Smith's Optics, 4to, vol. ii. p. 107 of Remarks.

" Though the Letters of a printed book appeared brighter and stronger — yet they do not seem at all larger when viewed with Both Eyes than when seen with One Only" — See Dr. Priestley on Vision, 4to. 1772, p. 669.

tion : — this pernicious plaything will most assuredly, in a very few Years, bring on an imperfect vision in One or Both Eyes.

Notwithstanding all the experience collected during the preceding 42 Years — the Third act of Life, i. e. from 42 to 63 — is as seldom performed properly, as either of the former. u The Art of Growing Old with a Good Grace" — I believe, is one of those, which the Ancients termed "Occult Arts" — and it appears to be almost as little understood, as that of communicating to our speedily perishing Body, the unchangeable nature of the incombustible Asbestos.

Query. Which appears most ridiculous 9 A Young Man pretending to the Sagacity and Experience of Age — or an Old Man affecting the Strength, and Apeing the Alertness of Youth ?

The only way that Persons can indulge their humour of appearing Purblind with impunity, is to use —

18 SPECTACLES WITH PLAIN GLASSES.

Chapter II. Spectacles With Plain Glasses

These should be kept by all Opticians, — who are not seldom puzzled and plagued by more nice than wise folks, who without any need of Spectacles, yet hearing their acquaintance talk of how charmingly they can see in Glasses, they long, like " the Italian Count,* to be better than weir' — and will not believe, that although they have not the least occasion for Optical assistance, yet, without trying all sorts of Glasses, cannot be convinced, that however this branch of Optics may alleviate the infirmity of the Eyes, as a Hearing Trumpet does that of the Ear, yet that when the Eyes are in a healthful state, they can receive no more assistance from Glasses, for the ordinary purposes of the Sight — than a person who is not Deaf can from a Hearing Trumpet — which, although so serviceable to a person who is deaf, is not of the least use to one who is not deaf.

* Whose Epitaph is — "I was well — wished to be better — Took Physic — and Died."

SPECTACLES WITH PLAIN GLASSES. 19

" Why has not man a Microscopic Eye ? For this plain reason, Man is not a Fly. Say what the use, were finer Optics given T' inspect a Mite, not comprehend the Heaven ! God, in the nature of each being, founds Its proper bliss, and sets its proper bounds.

Pope.

That ingenious Optician, the late Mr. Jesse Ramsden, informed me, that he had ofttimes more trouble to make obstinate and ignorant persons understand that the Art of Optics could not be of any service to them, than he had to find Glasses for correcting the most eccentric aberrations from good Vision — and that he found the only plan of completely convincing such troublesome Customers was, after he thought that they had sufficiently amused themselves with trying a variety of Glasses, — and had tired him, — to give them a pair of Spectacles glassed with plain Glass — when they would cry out with rapture — "Aye, these will do, I can see charmingly in these — why — why didn't You give me these at first?! !!"

Nothing, short of such ocular demonstration, could satisfy them.

20 CASE OF A PERSON, &C.

Chapter III. Case Of A Person Who Could Not Read In Spectacles

Mr. R. told me that he was once strangely puzzled, by a clever Old Gentlewoman of 79 years of age, for whom he was requested to make a pair of Spectacles. — She had applied in vain, to several eminent Opticians, and no Glass could be found that improved,, her Sight.

With all that Ambition to overcome difficulties, which was the ruling passion of Jesse Ramsden, he waited upon the Lady, with several pairs of Convex, and of Concave Spectacles, making quite sure, that however others had failed, he should succeed, and enjoy one of those triumphs, which constituted the Zest of his Existence, — but after patiently trying every one of them, She said with a Sigh ! — " No, — not one of these will do — I can see better with my Naked Eye. Well ! what an unfortunate Creature I am, at my Age, not to be able to see to read in Spectacles ! ! "