736 BLOOD BLOODHOUND times, the quantity of fibrine increases in the blood. There must be a very considerable formation of fibrine in the blood, as, according to the remarks of Brown-Sequard, there are many pounds of this substance transformed into other substances, in the course of a day, in the liver and the kidneys. The origin of the fats of the blood, as Persoz, Liebig, Bidder and Schmidt, and others, have well proved, is not exclusively from the fats of the food. But it remains to be shown from what principles of tlie food or of the blood, and in which organ, the formation of fat takes place. Many of the extractive substances of the blood are either formed in it or in the tissues. As to the salts and the metals of the blood, they come from the food. The sugar of the blood comes in a great measure from the food, and from a trans- formation of certain substances by the liver. VII. USES OF THE BLOOD. Nutrition that is, the act by which the various tissues grow or are maintained alive, and by which they ex- crete materials which are no longer useful to their organization and vital properties is the result of the interchange between the blood and the tissues. We will now examine how far some elements of the blood may influence the vital properties of the tissues, to show that these properties depend upon some materials furnished by the blood. Brown-Sequard has discovered that all the nervous and contractile tissues in the brain, the spinal cord, the motor and sensitive nerves, the muscles of animal or organic life, the iris, the skin, &c., may, after having lost their vital properties, their life, re- cover these properties again, and in some re- spects be resuscitated, when blood containing a great quantity of oxygen is injected into the arteries of all these parts. Still more, he has found that, when cadaveric or post-mortem rigidity exists in limbs of animals or men, oxy- genated blood has the power of restoring local life in these parts. These experiments he has made on many animals, and on the arms of two decapitated men, in one 13, in the other 14 hours after decapitation. He has ascertained that black blood (which contains but a small amount of oxygen) has no power of regenerat- ing the vital properties of the various tissues, and that the more blood corpuscles and oxygen there were in the blood employed, the quicker and the more powerful was its regenerating in- fluence. Blood deprived of fibrine acted as well as blood containing fibrine, showing that fibrine is not a necessary material for the pro- duction of the vital properties of the various tissues. In one case he maintained local life for 41 hours in a limb separated from the body of an animal. For other facts relating to the uses of the blood, see NUTRITION, SECRETION, and TRANSFUSION; for the circulation of the blood, see CIRCULATION. BLOOD, Thomas, an Irish adventurer, general- ly known as Colonel Blood, born about 1628, died in Westminster, Aug. 24, 1680. He was a disbanded officer of Cromwell's army. In 1663 he formed a conspiracy to surprise the castle of Dublin, which was defeated by flic vigilance of the duke of Ormond, the lord lieu- tenant, and some of the conspirators were exe- cuted. Blood escaped to England, determined to be revenged upon the duke. One night in 1670 he seized the duke while riding in his coach through St. James street, London, bound him on horseback behind an accomplice, and declared that he would hang him at Tyburn. The duke was finally rescued by his servants. In 1671 Blood nearly succeeded in carrying otf the crown and regalia from the tower of London. It was now for the first time dis- covered that he was the perpetrator of the as- sault upon Ormond. Charles II., at the insti- gation of Buckingham, who is supposed to have employed Blood, granted the felon an interview, and not only pardoned him, but gave him an estate in Ireland of 500 a year, and made him a special favorite. Blood enjoyed the pension for 10 years, but, being charged with circulating a scandal against the duke of Buckingham, was held to bail, and died in his own house before the trial came on. BLOODHOUND (canis familiaris), a hound trained for the pursuit of men, wounded ani- mals, or beasts of prey. The bloodhound is not peculiarly ferocious, as its name would im- Bloodhound (Canis familiaris). ply, and will hunt any other game to which he is trained as readily as he will man ; and many other dogs may be trained more or less per- fectly to follow the scent of man, as must be evident to every one who has seen a lost dog, which when he comes upon the scent of his master's foot will follow it until he has found him. Any hound naturally pursues whatever he perceives to be prey; and the distinc- tion of foxhound, staghound, harrier, boar- hound, or the like, is only a matter of educa- tion and training, and not of natural instinct. The bloodhound originally, of the old Talbot or southern breed, was larger than the fox- hound, tall, square-headed, slow, with long pendulous ears, heavy drooping lips and jowl, and a stern and noble expression. He was broad-chested, deep-tongned, and in pursuit so
