How to use the microscope, being practical hints on the selection and use of that instrument, intended for beginners

Front matter

jfreto f?ork

£?tate College of Agriculture

at Cornell tHntberSitp

Contents

Dedication. .-..,.. jj;

PREFACE. .... yjj

Inteoduction. - - - .- - - - - -xi

Preface To Third Edition

This might with propriety be called the fourth edition— the main idea of the work having been embodied in a pamphlet under the same title, published in 1878. but long since forgotten. The successive editions have reached their present form by accretion, rather than by development; like Topsey. the book has "growed," rather than been ' brought up. and just as that young lady exhibited numerous traits which were inconsistent with a proper training, so this book shows patch-work and inequalities which do not add either to its value or its attractiveness.

Of all this the author is fully conscious, and if he could possibly have secured the necessary leisure he would gladly have rewritten the entire volume. But pressing, or rather imperative calls upon his time, have prevented this, and he has.'therefore. been compelled to feel satisfied' with such general revision and additions as were necessary to bring the work up to the present state of our knowledge.

The book is still intended for beginners and has changed nothing of its elementary character. It is true that we have inserted a few pages relating to the higher class of objectives, and the accessories used with them, but those who do not possess such apparatus can easily skip these passages.

That it is suited to the purpose for which it was intended, we have evidence, not only in the extended sale which it has secured, but in the fact that it has been adopted as an auxiliary text-book in sevei-al of our schools and colleges.

New York, January, 1881.

Preface To Second Edition

The fact that an unusually large edition of this work has been sold in a comparatively short period, is, to the author, evidence that such a work was needed, and that the present volume has, to a certain extent, supplied the want. In the present edition, therefore, he has endeavored to introduce several important improvements, while at the same time the elementary character of the work remains unaltered. With a few very slight and unimportant exceptions, the entire matter of the former edition has been incorporated in the present, and in addition several important subjects, particularly the chapter on objectives, have been greatly enlarged.

Tm ttffifAOS.

Many important points still romaju untouched, but it is believed that in its present form most beginners will And in it all the information that they may require upon general topics.

As the want of all illustrations of the stands of different makers, and of many accessories, has been urged as an objection to the first edition, and as we have not deemed it advisable to fully supply this omission in the present issue, a word of explanation may not be out of place. One great object in view in the preparation of this book was the furnishing of a cheap manual for those who cannot afford the more expensive books of Carpenter, Beale, Frey, etc. To have given anything like a fair representation of the products of the different makers of this country and of Europe, would have nearly doubled the size and price of the volume. But if the reader will examine the engravings of stands, etc., in the books just mentioned, he will find that, even in the best of them, these illustrations are mere reproductions of the figures found in the descriptive lists of the various dealers. As new editions of these lists are being constantly issued, and as they may in most cases be obtained without cost from those that publish them, we have thought it best to refer our readers to these catalogues for information in regard to the construction of the instruments of different makers. Forthe addresses of the prominent microscope makers of this country and Europe we refer our readers to "The Microscopist's Annual."

In this, as in the previous edition, we have omitted all descriptions of objects, believing that the proper aim of a book on the microscope should not be to teach the general principles of botany, zoology or histology, but simply the best methods of using the microscope in the pursuit of these studies. The proper books in which to find a description of objects, are those which treat of that department of science which takes cognizance of the special subject under consideration. The present volume is intended merely as a guide to the best general methods of using the microscope.

It has been a source of great satisfaction to the author to be assured by those whom he deems good authority, that this little book has done much to foster the use of the microscope in this country, and he hopes that the present improved edition will tend to still further increase the deep interest which is already felt in an instrument which has done more than any other to extend our knowledge of organic nature.

New York. August, 1877.

Preface

The Microscope and its applications in the Arts, and in general science, having deservedly occupied a prominent place in the pages of The Technologist, or Industrial Monthly, a very large number of enquiries in regard to the best methodB of using and applying this useful instrument have been directed to us. It would have been easy to answer these enquiries by a reference to some one of the many treatises tliat have been published on this subject, but as most of these works are expensive, and a3 many of our correspondents desire an answer in a more concjse and simple shape, we have endeavored to give, in cheap and compact form, the information that is most usually demanded.

It is an unfortunate fact that while the microscope is daily growing in favor with those who know anything of its achievements, the operations of certain parties, too well known to the public, have brought a certain degree of suspicion upon all attempts to popularize this most valuable instrument. Microscopes, varying in price from twenty-five cents to two dollars and a half have been offered for sale, and the claim made for them that they are capable of showing clearly the structure of the more minute tissues, and that they may be used to advantage by physicians and naturalists. To the young student whose means are limited, and to the country practitioner, whose ability to supply himself with needed books and instruments often falls far short of his desires, the offer of a serviceable microscope for a couple of dollars is a great temptation, and when the instrument in question is endorsed by a long list of clergymen; lawyers, and even editors, this temptation becomes irresistible. And if the purchaser should happen to be unfamiliar with really good microscopes, and unable to discriminate between a clear and accurately defined view of any object and one that is distorted and incorrect, he may be led to use it, and so fall into the most serious mistakes. That this, unfortunately, does happen too often must be well known to all who are familiar with the subject, and it is within our own knowledge that the most worthless cari-

X TtfBVAGA

cature of a microscope has been purchased and used under such circumstances.

We indulge a faint hope that the information conveyed in the following pages will enable the inexperienced reader to avoid these mistakes, and to assign a proper value to the certificates of clergymen and editors who vouch for the excellence of articles concerning whose properties and uses they are profoundly ignorant. These two classes we single out for reprobation, because — in this rsspect, at least — they seem to be sinners above all other men.

As stated in the title page, it is intended for beginners, and not for beginners in the use of the microscope only, but for those who have had little or no experience in the use of instruments of any kind. Hence the directions that are given are of the very simplest kind, and all theoretical explanations have been avoided, for the reason that any person that is desirous of studying the optical principles upon which the microscope is constructed will find in the ordinary text book's on natural philosophy all the information he may want. Our object has been solely to impart such information as will enable the reader to make a beginning in the practice of microscopy, hoping that the start thus given will lead him to proceed with his studies, and ultimately acquire that knowledge, skill and dexterity which will enable him to avail himself of the extraordinary powers and advantages which the use of this instrument confers, both in scientific pursuits and in everyday life. Above all things, therefore, we have endeavored to be accurate in our statements and judicious in our directions, and the reader is assured that no processes or methods are given which we ourselves have not frequently and successfully put in practice.

JOHN PHIN.

New York, January, 1875,