Block, s. A short heavy piece of timber; a sea term for a pulley.
In Falconry, a solid piece of wood, shaped like a sugar loaf, with the six upper inches broken off, whereon the hawk perches, being tied to it by the leash, which goes through the last link of a small iron swivel fixed in its side.—Campbell.
Blood, s. The red liquor that circulates in the bodies of animals.
Blood, v. To stain with blood; to inure to blood, as a hound.
In essential characters and properties, blood is the same in all animals: in some, it wants the colouring matter, but it is invariably red in the higher orders, though the intensity of its hue varies with circumstances, the principal instance of which is that afforded between the venous and arterial; where it is, in the former, almost purple, but in the latter a bright scarlet.
The specific gravity of the blood is very differently estimated, it being subject to increase and decrease at different times. Disease and emaciation make it lighter, while in the contrary states, from its more perfect organisation, it is found heavier. If water be estimated at 1000, the specific gravity of blood may be reckoned at 1050; from which it may, however, be increased to 1120. Venous blood is heavier than arterial, as 1052 is to 1049; but these data vary.
The temperature of the blood in the horse is about 100°; in the ox, 102; and in the sheep, 103: but various circumstances tend to increase or decrease it. Arterial blood is usually one or two degrees warmer than venous: Mr. Vines, I believe, rates the difference much higher. Some diseases reduce the heat of the blood, and ardent inflammations are also capable of augmenting it. The quantity that an animal contains, in proportion to his bulk, has been endeavoured to be ascertained: but the results have been various. Very fat animals are found usually to have proportionally less than lean ones; and in those in a state of close confinement, the quantity is found to be smaller than in the wild; but it is evident, that as the calculation must be in a degree imaginary, from that which will remain in the vessels, so the real quantity is not easy to estimate. A medium sized horse has lost forty-four pounds without apparent injury, and most of them will lose one-fifteenth of their total weight before life becomes extinct: it may, therefore, be presumed that it forms one-tenth of the whole: Mr. Percivall thinks one-eighth.
Blood-hound (Canis Sanguinarius), s. A hound that follows by the scent.
In the darker ages the blood-hound had the fabulous reputation of pursuing naturally with unerring precision, and of taking murderers, robbers, and other depredators, if he were laid on the footsteps of those intended to be pursued, within a certain given time. We, however, cannot give our assent to the character thus ascribed to him, although experience has taught us, that all sorts of hounds may be broken in to follow any kind of scent, when resolutely taught that they are to run on no other.