This disease is, however, regarded by the author as infectious; by which term is meant that it is capable of being communicated from the diseased to the healthy animal through the medium of the air, which has become contaminated by the exhalations of poisonous matter. The ability to inoculate other animals in this way is necessarily confined to a limited space, sometimes not extending more than a few yards. Infectious diseases, accordingly, spread with more rapidity than contagious ones, and are, consequently, more to be dreaded; since we can avoid the one with comparatively little trouble, while the other often steals upon us when we regard ourselves as beyond its influence, carrying death and destruction in its course. The term by which this disease is known, is a misnomer. Pleuro-pneumonia proper is neither a contagious, nor an infectious disease; hence, the denial of medical men that this so-called pleuro-pneumonia is a contagious, or infectious disease, has been the means of unnecessarily exposing many animals to its poisonous influence. In the _Recueil de Medecine Veterinaire_, for 1833, will be found a very interesting description of this fatal malady. The author, M. Lecoy, Assistant Professor at the Veterinary School of Lyons, France, says: "There are few districts in the _arrondissement_ of Avesnes where more cattle are fattened than in that of Soire-le-Chateau. The farmers being unable to obtain a sufficient supply of cattle in the district, are obliged to purchase the greater part of them from other provinces; and they procure a great number for grazing from Franche Comte. The cattle of this country are very handsome; their forms are compact; they fatten rapidly; and they are a kind of cattle from which the grazer would derive most advantage, were it not that certain diseases absorb, by the loss of some of the animals, the profits of the rest of the herd. Amongst the diseases which most frequently attack the cattle which are brought from the North, there is one very prevalent in some years, and which is the more to be dreaded as it is generally incurable; and the slaughter of the animal, before he is perceptibly wasted, is the only means by which the farmer can avoid losing the whole value of the beast.