Pleasures and Uses of Microscopy—Development of the Microscope—Extemporised Apparatus.

Within the last half-century the use of the microscope, not only as an instrument of scientific research, a tool in the hands of the investigator of the finer organisation of the world of nature, nor even as an adjunct to the apparatus of the chemist or the manufacturer, but as a means of innocent and instructive recreation, has become so firmly rooted amongst us that it seems hardly necessary to advocate its claims to attention on any of these grounds.

So wonderful is the information which it affords, so indispensable is it in many, if not in all, branches of scientific research, that not only would the lover of nature be deprived of one of his most valued sources of information and enjoyment, but some sciences would be brought absolutely to a standstill if by any conceivable means the microscope were to be withdrawn from their followers.

On the other hand, from every improvement in the construction of the latter, a corresponding enlargement and enlightenment of the fields reviewed by these sciences has taken place, and the beauty and interest of the revelations made by its means has attracted an ever-increasing host of earnest and intelligent volunteers, who have rendered yeoman service to the cause of knowledge.

Moreover, so vast is the scope of the instrument, that whilst discoveries in other fields of research are few and far between, comparatively speaking, in microscopic science they are of everyday occurrence, and the number of problems calling for solution by means of the instrument in question is so vast that even the humblest worker may be of the greatest assistance.

In the following pages we propose to carry out, as far as possible with reference to the microscope, the system followed in the “Common Objects of the Seashore and of the Country,” and to treat in as simple a manner as may be of the marvellous structures which are found so profusely in our fields, woods, streams, shores, and gardens. Moreover, our observations will be restricted to an instrument of such a class as to be inexpensively purchased and easily handled, and to those pieces of supplementary apparatus which can be extemporised at small cost of money and ingenuity by the observer himself, or obtained of the opticians for a few shillings.

With the same view, the descriptions will be given in language as simple and as free from technicalities as possible, though it must be remembered that for many of the organisms and structures which we shall have to describe there are none but scientific names; and since, moreover, this little work is intended to furnish a stepping-stone between the very elements of microscopic science, and those higher developments of it which should be the aim of every worker, it would be unwise to attempt to invent commonplace appellations for the purpose of this book, and leave him to discover, when he came to consult works of reference in any particular subject, that his “simplified” knowledge had all to be unlearnt, and a new vocabulary acquired. Rather will it be our purpose to use correct terms, and explain them, as far as necessary, as we introduce them.

The commencing microscopist is strongly recommended, whilst not confining his interest entirely to one branch of research or observation, to adopt some one as his particular province.

The opportunities for discovery and original work, which are afforded by all alike, will be more readily appreciated and utilised by adopting such a plan than by a general and purposeless distribution of effort. To mention one or two. The student of the fascinating field of pond-life will find new organisms awaiting description by the hundred, and of the old ones, life-histories to make out; if he be attracted rather to the vegetable inhabitants of the same realm, the diatoms will furnish him with the opportunity of studying, and perhaps solving, the enigma of their spontaneous movement, and of watching their development. The smaller fungi, and indeed the larger ones too, will amply repay the closest and most laborious study of their habits of life and processes of development. Since the first edition of this work was published, the whole subject has been practically revolutionised, and more remains to be done than has yet been accomplished.

In short, there is scarcely an organism, even of those best known and most studied, which is so completely exhausted that persevering investigation would reveal nothing new concerning it.

There can be little doubt but that if any worker, with moderate instrumental means, but with an observant mind, were to set determinately to work at the study of the commonest weed or the most familiar insect, he, or she, would by patient labour accomplish work which would not only be of value to science, but would redound to the credit of the worker.

Something like finality appears to have been reached, at least for the present, in the development of the microscope; and whilst it is beyond the scope of this work to treat of the refined and costly apparatus which is essential to useful work in certain departments of research, the result has, on the whole, been highly favourable to the worker of moderate means and ambitions, since lenses are now accessible, at the cost of a few shillings, comparatively speaking, which could not have been purchased at all when this work first appeared. It is with such appliances that we have here to deal. The worker whose finances are restricted must be contented to extemporise for himself many pieces of apparatus, and will find pleasure and occupation in doing so. And let him remember, for his encouragement, that many such home-made appliances will fulfil their purpose quite as well as the imposing paraphernalia of glittering brass and glass which decorates the table of the wealthy amateur. It is not the man who possesses the best or most costly apparatus, but the one who best understands the use of that which he possesses, that will make the most successful microscopist. A good observer will discover, with only the aid of a pocket-magnifier, secrets of Nature which have escaped the notice of a whole army of dilettante microscopists, in spite of the advantages which, as regards instruments, the latter may enjoy.

It is for those who desire to be of the former class that this book is written, and in the course of the following pages instances will be given in which the exercise of a small amount of ingenuity and the expenditure of a few pence will be found equivalent to the purchase of costly and complicated apparatus.

An enormous amount of valuable work was done in the earliest days of microscopy, when the best apparatus available was a single lens, composed of the bead formed by fusing the drawn-out end of a rod of glass. Inserted into a plate of metal, or a piece of card, such a primitive instrument was capable of affording a large amount of information. Similar instruments are to be purchased for a few pence at the present day, and are not without their use for purposes of immediate examination of material. A very common form is a glass marble, ground flat on one side, and mounted in a tube. The material to be examined is placed upon the flat side, and is seen magnified to an extent inversely proportional to the diameter of the sphere of glass.