BY THOMAS DAVIES. LONDON : ROBERT HARDWICKE, 192, PICCADILLY. AND ALL BOOKSELLERS. A New Edition, Revised and Enlarged. Price 2s. 6d. plain; 4s. coloured. HALF-HOURS WITH THE MICROSCOPE. A Popular Guide to the Use of the Microscope as a Means of Amusement and Instruction. With Drawings of 250 objects from Nature, by TUFFEN WEST. By E. LANKESTER, M.D., F.R.S. CONTENTS: Half an hour on the Structure. Half an hour in the Garden. Half an hour in the Country. Half an hour at the Pondside. Half an hou

In bringing this Handbook before the public, the Author believes that he is supplying a want which has been long felt. Much information concerning the “Preparation and Mounting of Microscopic Objects” has been already published; but mostly as supplementary chapters only, in books written professedly upon the Microscope. From this it is evident that it was necessary to consult a number of works in order to obtain anything like a complete knowledge of the subject. These pages, however, will be fou

Before entering into the subject of the setting of Objects for the Microscope, the student must be convinced of the necessity of cleanliness in everything relating to the use of that instrument. In no branch is this more apparent than in the preparation of objects; because a slide which would be considered perfectly clean when viewed in the ordinary way is seen to be far otherwise when magnified some hundreds of diameters; and those constant enemies, the floating particles of dust, are everywher

The term “dry” is used when the object to be mounted is not immersed in any liquid or medium, but preserved in its natural state, unless it requires cleaning and drying. I have before stated that thorough cleanliness is necessary in the mounting of all microscopic objects. I may here add that almost every kind of substance used by the microscopist suffers from careless handling. Many leaves with fine hairs are robbed of half their beauty, or the hairs, perhaps, forced into totally different shap

The nature and use of this substance has been before spoken of, so the method of working with it may be at once described. Perfect dryness of the objects is, if possible, more necessary in this mode of mounting than any other, as dampness remaining in the object will assuredly cause a cloudiness to make its appearance in a short time after it is fixed. Where pressure does not injure the specimens, they are most successfully treated when first dried betwixt the leaves of a book, or in any other w

There are many objects which would lose all their distinctive peculiarities if allowed to become dry, especially those belonging to the fresh-water Algæ, many animal tissues, and most of the very delicate animal and vegetable substances in which structure is to be shown. These must be preserved by immersion in some fluid; but it is evident that the fluid must be suited to the kind of matter which it is intended to preserve. As it often requires much study and trouble to obtain microscopic object

Many objects are almost worthless to the microscopist until the extraneous matter is removed from them; and this is frequently difficult in the extreme to perform satisfactorily. As an instance, certain Foraminifera may be mentioned in which the cells are placed one upon another, consequently the object must be reduced to a certain degree of thinness before a single uniform layer of these cells can be obtained to show something of the internal arrangements. Most animal and vegetable forms requir

1. Injection is the filling of the arteries, veins, or other vessels of animals with some coloured substance, in order that their natural arrangement may be made visible. This is, of course, a delicate operation, and needs special apparatus, which I will now attempt to describe. 2. Syringe. —This is usually made to contain about two ounces. On each side of the part next to the handle is a ring, so that the finger may be thrust through it, and the thumb may work the piston as in an ordinary syrin

It must be evident to all readers that there are various objects of interest to the microscopist which cannot be properly placed amongst any of the forementioned classes, but must not be omitted in such a guide as this professes to be. Of these may be mentioned the circulation of the blood in various animals, the rotary motion of the fluid in many plants, the best means of taking minute photographs, &c. &c. Perhaps the most interesting of these objects is the circulation of the b