3. The evidence is just as indubitable that exhalations arise from the bodies of the dead, which are capable of producing disease and death. Many instances are recorded of the communication of small-pox from the corpse of a person who has died of small-pox. This has happened not only in the dwelling-house before interment, but even in the dissecting room. Some years ago five students of anatomy, at the Webb-street school, Southwark, who were pursuing their studies under Mr. Grainger, were seized with small-pox, communicated from a subject on the dissecting-table, though it does not appear that all who were attacked were actually engaged in dissecting this body. One of these young men died. There is reason to believe that emanations from the bodies of persons who have died of other forms of fever have proved injurious and even fatal to individuals who have been much in the same room with the corpse. The exhalations arising from dead bodies in the dissecting room are in general so much diluted by admixture with atmospheric air, through the ventilation which is kept up, that they do not commonly affect the health in a very striking or marked manner; and by great attention to ventilation, it is no doubt possible to pursue the study of anatomy with tolerable impunity. Yet few teachers of anatomy deny that without this precaution this pursuit is very apt to injure the health, and that, with all the precaution that can be taken, it sometimes produces such a degree of diarrhœa, and at other times such a general derangement of the digestive organs, as imperatively to require an absence for a time from the dissecting room and a residence in the pure air of the country. The same statements are uniformly made by the professors of Veterinary anatomy in this country. The result of inquiries which I have personally made into the state of the health of persons licensed to slaughter horses, called knackers, is, that though they maintain their health apparently unimpaired for some time, yet that after a time the functions of the nutritive organs become impaired, they begin to emaciate, and present a cadaverous appearance, slight wounds fester and become difficult to heal, and that upon the whole they are a short-lived race.