It was also an accepted belief that diseases could be transferred to animals, and even to vegetables. Cures held to be so effected were, according to one medical theory, cures by "sympathy." A few instances, culled from a work published during the latter half of the seventeenth century (1663), entitled _The Usefulness of Experimental Philosophy_, will illustrate this theory:--A medical man had been very ill of an obstinate _marasmar_ (?) which so consumed him that he became quite a skeleton, notwithstanding every remedy which he had tried. At length he tried a sympathetic remedy: he took an egg, and having boiled it hard in his own urine, he then with a bodkin perforated the shell in different parts, and then buried it in an ant-hill. As the ants wasted the egg he found his strength increase, and he soon was completely cured. A daughter of a French officer was so tormented by a _paronychia_ (?) for four days together, that the pain kept her from sleeping; by the order of a medical man she put her finger into a cat's ear, and within two hours was delivered from her pain. And a councillor's wife was cured of a _panaritium_ (?) which had vexed her for four days by the same means. In both cases the cat had received the pain in its ear and required to be held. The gout is cured by sympathy: by the patient sleeping with puppies, they take the disease, and the person recovers. A boy ill with the king's evil could not be cured, his father's dog took to licking the sores, the dog took the sores, and the boy was completely cured. A gentleman having a severe pain in the arm was cured by beating red coral with oak leaves, and applying it to the part affected till suppuration: a hole was then made in the root of an oak towards the east, and the mixture put into it and the hole plugged up with a peg of the same tree, and from that time the pain did altogether cease; and when afterwards the mixture was removed from the tree, immediately the torments returned worse than before. Sir Francis Bacon records a cure of warts: he took a piece of lard with the skin on it, and after rubbing the warts with it the lard was exposed out of a southern window to putrify, and the warts wore away as it putrified. Harvey tried to remove tumours and excrescences by putting the hand of a dead person that had died of a lingering disease upon them till the part felt cold. In general the application was effective. This idea of cure by sympathy retained its hold on the people till this century, and is not yet entirely gone.