How else than on the principle of infection, and not of contagion, can we explain the attack of individuals frequenting those parts of the city, where the disease had originated, and which (all the inhabitants having been removed to some distant situation) had been barricaded? How could we, in any other way, account for the exemption from the fever of individuals, who, out of the infected district, nursed, touched, and even slept with their diseased relatives and friends; and not always in clean and well ventilated apartments and parts of the city; but, in very many instances, in the filthiest hovels, and alleys, and among the lowest classes of society. Striking and unanswerable facts of the sort have frequently presented themselves to my observation, during our various epidemics. Children have sucked their parents, affected with the fever, and, in one case which fell under my notice, the child continued attached to the breast after its mother's death; and in all such instances with impunity. I have constantly reprobated the practice of burning the clothes and bedding of the dead, and have never found any bad results to occur to those who followed my advice. From a consideration of all these facts, I must once more express it as my decided opinion, that the yellow fever, so far as I have had an opportunity of observing it, is not a contagious disease. _Treatment._--Whatever opinion we may entertain respecting the specific nature of yellow fever, I was early convinced that this disease was not to be treated by specific remedies, and that our curative indications should be formed on an attentive consideration of the condition of the system in general, and of particular organs, as pointed out by the symptoms during life and the morbid lesions after death.