Essays on the Microscope Containing a Practical Description of the Most Improved Microscopes, a General History of Insects, etc., etc.

A B C D, Fig. 4, represents the body of the microscope, consisting of two brass tubes. E F is the end of the inner moveable tube; _e f_, that of the single tooth and pinion micr...

If from the point A upon the right line C I, there be let fall the perpendicular A D, that line is called the sine of the angle of incidence.

These require little or no preparation. The first object is to procure them, the second, to render them visible by the microscope. A few observations, however, may be of use. Ma...

Place the lamp lighted before the glass lump n, and the object you intend to examine between the spring plates of the stage, and the instrument is ready for use.

The twenty-six divisions found on the strait scale of the micrometer, while the point of the needle passed over the magnified image of one-tenth part of an inch, were multiplied...

When a polype has nothing to eat, its mouth is generally open, but so small, that it can scarce be perceived without the assistance of a magnifying glass; but as soon as the arm...

As some objects, such as sections of wood, are seen to advantage both as transparent and opake, a frame containing a plane and a concave mirror is added to this instrument, serv...

Stagnant waters are generally filled with insects, who live therein in different manners. These are, 1. Aquatic insects which remain always on the superficies of the water, or w...

At the stage N I S, is a sliding brass spring, N, serving to confine down slips of glass or large sliders, when objects placed thereon are intended to be viewed out of the horiz...

November 25, a letter from Cambridge was read to the Royal Society, in which the author endeavours to lessen, by reason, the prejudices which then combated the belief of these f...

Sometimes he put into water the delicate viscera of the insects he had suffocated; and then shaking them gently he procured himself an opportunity of examining them, especially...

Each of these seeds, upon being bruised, divides into two hemispheres, Fig. 18, which discovers the edges of the rigid cortex, on the concave side there is a rising, and within...

The tail is constructed and planned with great skill and wisdom. The extreme verge or border, is surrounded by thirty hairs, and the sides adorned with others that are smaller;...

Plate XVI. Fig. 1. is a microscopic view of the proboscis of a tabanus, with which it pierces the skins of horses and oxen, and nourishes itself with their blood; Fig. 2. the sa...

The following names are made use of to describe the different kinds of wings. They are first distinguished, with respect to their surfaces, into superior and inferior. The part...

By the bark the tree is fed with a continual supply of moisture, protected from external injuries, and defended from the excesses of heat and cold; for these purposes it is vari...

These clusters are larger or smaller, according to the species of the vorticellæ which form them, as well as owing to the concurrence of many other circumstances. To obtain a cl...

The microscope, nearly at the same period, gave rise to M. Buffon’s famous system of organic molecules, and M. Needham’s incomprehensible ideas concerning a vegetable force and...

These subterraneous passages or galleries are lined very thick with the same kind of clay of which the hill is composed, and ascend the inside of the outward shell in a spiral m...

The termites resemble the ants, indeed, in their provident and diligent labour, but surpass them, as well as the bees, wasps, beavers, and all other animals, in the art of build...

From what has been said, it appears plainly, the advantages we gain by microscopes are derived, first, from their magnifying power, by which the eye is enabled to view more dist...

Chaos redivivum, Linn. Syst. Nat. 1326.[124] Leeuwenhoeck Opera Omn. p. 3, n. 1, f, l, o. Joblot Observ. Micros. 1, p. 2, pl. 2. Hooke’s Micrograph, p. 216, pl. 25, fig. 3. Bore...

The telescope is one of those which are composed of several sliding drawers or tubes, for the convenience of being put into the pocket; the sliding tubes are made of thin brass,...

It has already been observed, that the bodies of insects are covered with a hard skin, answering the purpose of an internal skeleton, and forming one of the characters by which...

The colour, while the fish is alive, is a fine pellucid crimson; when dead, is white. It is found alive on the fucus vesiculosus, and is a very common shell on all the coast, an...

A new polype is formed out of small portions or fragments, in a very different manner, the operations in nature being always varied, according as the circumstances differ; each...

It is a general rule, that all winged insects pass through the larva and pupa state, before they assume their perfect form: there are also insects which have no wings, and yet u...

The gnat, the ephemera, the phryganea, the libellula, hover over the water all day to drop their eggs, which are hatched in the water, and continue there all the time they are i...

“Some of these creatures crawl for a time as helpless worms upon the earth, like ourselves; they then retire into a covering, which answers the end of a coffin or a sepulchre, w...

Amongst insects, some are produced in the state in which they will remain during their whole lives; others come forth inclosed in an egg, and are hatched from this into a form t...

The construction of the single microscope is so simple, that it is susceptible of but little improvement, and has therefore undergone but few alterations; and these have been ch...

The substance of which the silk is formed, is a fine yellow transparent gum, contained in two reservoirs that wind about the intestines, and which, when they are unfolded, are a...

The ligneous fibres are very fine tubes, proceeding nearly in a vertical direction from the top to the bottom of the tree; they are sometimes parallel to each other, sometimes t...

Figures 1 and 2 represent the muscles of the caterpillar, when it is opened at the belly. Fig. 3 and 4 exhibit a view of the muscles when it is opened at the back. Fig. 5 and 6,...

375. BRACHIONUS URCEOLARIS. For a full description of this animalculum, being the same as the vorticella urceolaris, the reader will please to refer to page 408. Views of the an...

This extraordinary little creature was found by my ingenious friend, Mr. John Adams, of Edmonton; he was at the New Inn, Waltham Abbey, where it was spied by some labouring men...

This is also to be placed amongst the most minute animalcula; the end of it is rather pointed, and has a tremulous motion; it almost induces one to think it has a tail. Two of t...

When the configurations are fully formed, and all the water evaporated, most kinds of them are soon destroyed again by the moisture or action of the air upon them; their points...

Their habitations are exceedingly diversified: some are found in rotten and half decayed wood, and under the decayed bark of trees, as the lucanus cervus, flying stag, scarabæus...

Of all the different classes or orders of insects, that called LEPIDOPTERA is not only one of the most numerous, but the most beautiful, with respect to the variety as well as r...

If the smallest drop of urine be put into a drop of water where these animalcula are roving about, apparently happy and easy, they instantly fly to the other side, but the acid...

This is among the number of the smaller animalcula, nearly of a round figure, and so pellucid, that it is not possible to discover the least vestige of intestines. Though they m...

The gnat is a beautiful object for the microscope. The curious manner in which it disposes its eggs upon the surface of the water has been noticed in page 288. From the egg proc...

It appears plainly from the foregoing experiments, that when the blighted grains of wheat have been kept a long time, and the bodies of these animalcula are consequently become...

The subjects of that part of the creation we are now going to survey, merit our attention as exceeding the rest of animated nature in their numbers, the singularity of their app...

This is one of the most singular of the microscopic animalcula; when viewed sidewise, it is sometimes nearly cylindrical, but somewhat tapering towards the hinder-part, and havi...

Early in the month of June, some of the third generation, which were produced about the middle of May, after casting off their last covering, discover four erect wings, much lon...

These insects usually shelter themselves among the moss and other extraneous matters growing on the trunks or branches of trees, or beneath the rotten bark; these substances sho...

It bears some resemblance to the vorticella polymorpha, No. 290, and the vorticella viridis, No. 283, and requires to be observed for some time before its peculiar characters ca...

Below the thorax there is an annular circle that joins the thorax to the abdomen; this is considerably the largest part of the animal, and contains the stomach and viscera. When...

The body is cylindrical, pellucid, muscular, and capable of being folded up; it appears double; the interior part is full of molecules, with an orbicular muscular appendage whic...

This appears like a little quadrangular membrane, plain on both sides; with a large magnifier it looks like a bolster, formed of three or four cylindric pillows, flattened or su...

IV. ASTRONOMICAL AND GEOGRAPHICAL ESSAYS, containing, 1. A full and comprehensive View of the general Principles of Astronomy, with a large Account of the Discoveries of Dr. Her...

The mechanical powers, for illustrating and demonstrating the laws of motion, gravity, &c. a set neatly made in brass, consisting of the balance, the pullies, the different kind...

[170] Those who are desirous of seeing well delineated and elegantly coloured figures of a variety of curious objects among the insect class, particularly such as require invest...

Every work that tends to enlarge the boundaries of science has a peculiar claim to the protection of Kings. He that diffuses science, civilizes man, opens the inlets to his happ...

The following is a new, useful, and ready method of making globules for microscopes, differing from the customary one described in page 8, and is extracted from Mr. W. Nicholson...

The LUCERNAL MICROSCOPE, as improved by W. JONES, exhibiting images of opake and transparent objects by night or day, in a manner singularly pleasing, brilliant and distinct, wi...

Microscope, date of its invention, 1--name of inventor not known, ibid.--its excellence, 2, 23--early introduced by Jansens, 2--one brought to England by Drebell, ibid.--made by...