TRANSFUSION of Blood. an operation by which it has been imagined that the age of animals may be renewed. The method of transfusing Dr Lower gives us to the following effect. Take up the carotid artery of the dog, or other animal, whose blood is to be transfused into another of the same, or a different kind: separate it from the nerve of the eighth pair, and lay it bare above an inch. Make a strong ligature on the upper part of the artery; and an inch nearer the heart another ligature with a running knot, to be loosened and fastened as occasion requires. Draw two threads between the two ligatures, open the artery, put in a quill, and tie up the artery again upon the quill by the two threads, and stop the quill by a stick. Then make bare the jugular vein of the other animal for about an inch and a half in length, and at each end make a ligature with a running knot; and in the space between the two knots draw under the veins two threads, as in the other. Open the vein, and put into it two quills, one into the descending part of the vein, to receive the blood from the other dog, and carry it to the heart; the other quill put into the other part of the jugular, towards the head, through which the second animal’s own blood is to run into dishes. The quills being tied fast, stop them up with sticks till there be occasion to open them. Things being thus disposed, fasten the dogs on their sides towards one another, in such a manner as that the quills may go into each other; then unstop the quill that goes down into the second dog’s jugular vein, as also that coming out of the other dog’s artery; and by the help of two or three other quills put into each other, as there shall be occasion, insert them into one another. Then slip the running knots, and immediately the blood runs through the quills as through an artery, very impetuously. As the blood runs into the dog, unstop the quill in the upper part of his jugular, for his own blood to run out at, though not constantly, but as you perceive him able to bear it, till the other dog begins to cry and faint, and at last die. Lastly, take both quills out of the jugular, tie the running knot fast, and cut the vein asunder, and sew up the skin: the dog, thus dismissed, will run away as if nothing ailed him.

In the Philosophical Transactions we have accounts of the success of various transfusions practised at London, Paris, in Italy, &c. Sir Edmund King transfused forty-nine ounces of blood out of a calf into a sheep; the sheep, after the operation, appearing as well and as strong as before. Μ. Denis transfused the blood of three calves into three dogs, which all continued brisk, and ate as well as before. The same person transfused the blood of four wethers into a horse twenty-six years old, which thence received much strength, and a more than ordinary appetite. Soon after this operation was introduced at Paris, viz. in 1667 and 1668, M Denis performed it on five human subjects, two of whom recovered of disorders under which they laboured; one being in perfect health suffered no inconvenience from it; and two persons who were ill, and submitted to the operation, died; in consequence of which the magistrates issued an order, prohibiting the transfusion on human bodies, under pain of imprisonment. Mr John Hunter, we are told, made many ingenious experiments to determine the effects of transfusing blood, some of which are sufficient to attract attention. But whether such experiments can ever be made with safety on the human body, is a point not easily determined.