SPIRIT OF DISCOVERY
Aerial Voyages of Spiders.
The number of the aëronautic spiders occasionally suspended in the atmosphere, says Mr. Murray, I believe to be almost incredible, could we ascertain their amount. I was walking with a friend on the 9th, and noticed that there were four of these insects on his hat, at the moment there were three on my own; and from the rapidity with which they covered its surface with their threads, I cannot doubt that they are chiefly concerned in the production of that tissue which intercepts the dew, and which, illuminated by the morning sun, "glitters with gold, and with rubies and sapphires." Indeed, I have noticed that, when the frequent descent of the aëronautic spider was determined, a newly rolled turnip field was, in a few hours, overspread by a carpet of their threads. It may be remarked that our little aëronaut is very greedy of moisture, though abstemious in other respects. Its food is perhaps peculiar, and only found in the superior regions of the sky. Like the rest of its tribe, it is doubtless carnivorous, and may subserve some highly important purpose in the economy of Providence; such, for instance, as the destruction of that truly formidable, though almost microscopically minute insect, the Fùria infernàlis, whose wounds are stated to be mortal. Its existence has been indeed questioned, but by no means disapproved; that, and some others, injurious to man, or to the inferior creation, may be its destined prey, and thus our little aëronaut, unheeded by the common eye, may subserve an important good.
Mr. Bowman, F.L.S. says, "We arrested several of these little aëronauts in their flight, and placed them on the brass gnomon of the sundial, and had the gratification to see them prepare for, and recommence, their aerial voyage. Having crawled about for a short time, to reconnoitre, they turned their abdomens from the current of air, and elevated them almost perpendicularly, supporting themselves solely on the claws of their fore legs, at the same instant shooting out four or five, often six or eight, extremely fine webs, several yards long, which waved in the breeze, diverging from each other like a pencil of rays, and strongly reflecting the sunbeams. After the insects had remained stationary in this apparently unnatural position for about half a minute, they sprang off from the stage with considerable agility, and launched themselves into the air. In a few seconds after they were seen sailing majestically along, without any apparent effort, their legs contracted together, and lying perfectly quiet on their backs, suspended from their silken parachutes, and presenting to the lover of nature a far more interesting spectacle than the balloon of the philosopher. One of these natural aëronauts I followed, which, sailing in the sunbeams, had two distinct and widely diverging fasciculi of webs, and their position in the air was such, that a line uniting them would have been at right angles with the direction of the breeze."—Mag. Natural History.
The Ichneumon Fly.
There are several species of ichneumon which make thinnings among the caterpillars of the cabbage butterfly. The process of one species is this:—while the caterpillar is feeding, the ichneumon fly hovers over it, and, with its piercer, perforates the fatty part of the caterpillar's back in many places, and in each deposits an egg, by means of the two parts of the sheath uniting together, and thus forming a tube down which the egg is conveyed into the perforation made by the piercer of the fly. The caterpillar unconscious of what will ensue keeps feeding on, until it changes into a chrysalis; while in that torpid state, the eggs of the ichneumon are hatched, and the interior of the body of the caterpillar serves as food for the caterpillars of the ichneumon fly. When these have fed their accustomed time, and are about to change into the pupa state, they, by an instinct given them, attack the vital part of the caterpillar (a most wonderful economy in nature, that this process should be delayed until they have no more occasion for food.) They then spin themselves minute cases within the body of the caterpillar; and instead of a butterfly coming forth (which, if a female, would have probably laid six hundred eggs, thus producing as many caterpillars, whose food would be the cabbage,) a race of these little ichneumon flies issues forth, ready to perform the task assigned them, of keeping within due limits those fell destroyers of our vegetables.—Mr. Carpenter—in Gill's Repository.
Hawking.
Professional falconers have been for many years natives of the village of Falconsward, near Bois le Duc, in Holland. A race of them was there born and bred, whence supplies have been drawn for the service of all Europe; but as there has been no sufficient inducement for the young men to follow the employment of their forefathers, numbers are dead or worn out; and there only remains John Pells, now in the service of John Dawson Downes, Esq., of Old Gunton Hill, Suffolk.
The hawks which have been trained for the field, are the slight falcon and the goshawk, which are the species generally used in falconry. The former is called a long-winged hawk, or one of the lure; the latter, a short-winged hawk, or one of the fist.
The Icelander is the largest hawk that is known, and highly esteemed by falconers, especially for its great powers and tractable disposition. The gyr falcon is less than the Icelander, but much larger than the slight falcon. These powerful birds are flown at herons and hares, and are the only hawks that are fully a match for the fork-tailed kite. The merlin and hobby are both small hawks and fit only for small birds, as the blackbird, &c. The sparrow-hawk may be also trained to hunt; his flight is rapid for a short distance, kills partridges well in the early season, and is the best of all for landrails.
The slight falcon takes up his abode every year, from October and November until the spring, upon Westminster Abbey, and other churches in the metropolis. This is well known to the London pigeon-fanciers, from the great havoc they make in their flight.—Sir John Sebright
Technicalities of Science.
The inutility of science, written in a merely technical form, is well exemplified in the instance of Cicero. He was advised by his friends not to write his works on Greek Philosophy in Latin; because those who cared for it would prefer his work in Greek, and those who did not would read neither Greek nor Latin. The splendid success of his De Officiis, his De Finibus, his De Natura Deorum, &c., showed that his friends were wrong. He persevered in the popular style, and led the fashion.—Mag. Nat. Hist.
Doubtful Discoveries.
It may serve, in some measure, to confirm M. Dutroehet's recent opinion of the non-existence of miscroscopic animalcula, that the celebrated Spallanzani persuaded himself that he could see Animálcula infusòria which could be seen by nobody else. He attributed his own superiority of vision, in this respect, to long practice in using the microscope. The philosopher exulted in his enviable distinction, when a peasant, to whom he showed his animalcula, could perceive nothing but muddy water.—Ibid.
Faculties of Brutes.
The dog is the only animal that dreams; and he and the elephant the only animals that understand looks; the elephant is the only animal that, besides man, feels ennui; the dog, the only quadruped that has been brought to speak. Leibnitz bears witness to a hound in Saxony, that could speak distinctly thirty words.—Medical Gazette.
Sea Air.
The atmosphere, in the vicinity of the sea, usually contains a portion of the muriates over which it has been wafted. It is a curious fact, but well ascertained, that the air best adapted to vegetables is pernicious to animal life, and vice versa. Now, upon the sea-coast, accordingly, animals thrive, and vegetables decline.—Hurwood's Southern Coast.