On August the 4th, 1775, we surprised a large viper, which seemed very heavy and bloated, as it lay in the grass basking in the sun. When we came to cut it up, we found that the abdomen was crowded with young, fifteen in number; the shortest of which measured full seven inches, and were about the size of full grown earthworms. This little fry issued into the world with the true viper spirit about them, showing great alertness as soon as disengaged from the belly of the dam: they twisted and wriggled about, and set themselves up, and gaped very wide when touched with a stick, showing manifest tokens of menace and defiance, though as yet they had no manner of fangs that we could find, even with the help of our glasses.
To a thinking mind nothing is more wonderful than that early instinct which impresses young animals with the notion of the situation of their natural weapons, and of using them properly in their own defence, even before those weapons subsist or are formed. Thus a young cock will spar at his adversary before his spurs are grown: and a calf or lamb will push with its head before its horns are sprouted. In the same manner did these young adders attempt to bite before their fangs were in being. The dam, however, was furnished with very formidable ones, which we lifted up (for they fold down when not used) and cut them off with the point of our scissors.
There was little room to suppose that this brood had ever been in the open air before; and that they were taken in for refuge, at the mouth of the dam, when she perceived that danger was approaching; because then probably we should have found them somewhere in the neck, and not in the abdomen.—White’s Selborne.
Viperous, a. Having the qualities of a viper.
Viscera, s. The bowels or entrails.
Viscera of the horse.—The alimentary canal is continued from the expellent orifice of the stomach to the anus, or end of the passage; forming a long canal, whose varying dimensions have occasioned it to be divided into the small and large intestines. The length of the tract ranges between twenty-seven and thirty yards; of which proportions the small intestines occupy from twenty to twenty-two yards, and the large from seven to eight. It is not easy to give a determinate place to the intestines, either individually or generally; the large, however, may be said to occupy all the inferior portion of the abdomen throughout, and the small to range between and upon them; both occasionally shifting their position by the peristaltic motion. They are, however, prevented from an unnatural displacement, by membranous productions of the peritoneum, under the name of mesentery, mesocolon, and mesorectum. The first intestinal coat is derived from the peritoneum, which separates to receive the tube between its lamen; at once protecting it, and affording a medium for the transmission of its vessels and a lubricating surface. The second, or muscular coat, presents a longitudinal and a circular plan of fibres; by the contraction of which, the vermicular motion, called peristaltic, is performed, the longitudinal slightly shortening them, and the circular diminishing their diameter; the inner surface of this fabric being garnished with a quantity of dense cellular tissue, was formerly erroneously considered as another and a nervous coat. The inner tunic of the intestinal canal is villous, or mucous, and is very vascular and sensible, its villi presenting an increased surface for the mucous secretion, as well as more numerous chyliferous orifices, with which it is thickly studded; but it presents no valvulæ conniventes, as in the human, their place being supplied by the increased length of the tract.—Blaine.
Viscous, a. Glutinous, sticky, tenacious.
Vision, s. Sight, the faculty of seeing; the act of seeing.
Vision of Birds.—Ross, in his voyage to Baffin’s Bay, proved that a man under favourable circumstances could see over the surface of the ocean to the extent of one hundred and fifty English miles. It is not probable that any animal exceeds this power of vision, though birds, perhaps, excel men and most quadrupeds in sharpness of sight. Schmidt threw at a considerable distance from a thrush (Turdus musicus) a few small beetles, of a pale grey-colour, which the unassisted human eye could not discover, yet the thrush observed them immediately and devoured them. The bottle tit (Parus caudatus,) flits with great quickness among the branches of trees, and finds on the very smooth bark its particular food, where nothing is perceptible to the naked eye, though insects can be detected there by the microscope. A very tame red-breast (Sylva rubecula, Latham,) discovered crumbs from the height of the branch where it usually sat, at the distance of eighteen feet from the ground the instant they were thrown down, and this by bending its head to one side, and using of course only one eye. At the same distance a quail discovered, with one eye, some poppy-seeds, which are very small and inconspicuous.—Montagu.
Vitriol, s. Vitriol is produced by addition of a metallic matter with the fossil acid salt.