“It is well known to what an extent various diseases, such as cutaneous complaints and scurvy, have identified themselves with peculiar situations, more especially after certain seasons. Medical practitioners are of opinion, that, for the thoroughly comprehending the nature and the cure of endemical diseases, an accurate study of topography is essentially necessary. The inhabitants of countries or places where diseases prevail endemically are very often exempted from other serious indispositions; and the natives of a country or district frequently become inured by habit to influences which at once manifest their power over newly-imported strangers, especially in tropical regions. In countries inhabited by different races of men, the same circumstances do not always produce the same effects upon different varieties. The water of the Seine produces disorder in the Londoner, to which the Parisian, who is accustomed to it, is exempt. The treatment also of similar diseases often requires to be very different in consequence of the locality where it appears, and also the constitution and habits of the patient. “The miasmata, or particles which emanate from the surface of the earth, produce marked effects upon the human constitution in those places where they prevail. The districts where they are most conspicuous are the marshes, fens and swamps in Lincolnshire, Cambridgeshire, and Essex: intermitting fevers and agues are the consequence. Although marshy districts are pre-eminently capable of engendering miasmata, they are not exclusively so: the result of numerous observations proves that the circumstances essential to this phenomenon are the presence of water, or moisture, and the influence of solar heat: when the quantity of water is great at any particular time, the effects do not manifest themselves until it subsides. Many circumstances are supposed to influence the development of the effects of these exhalations. It is also asserted, that it has sometimes been carried to considerable distances, to situations naturally healthy, by currents of air. This is a consideration of vast importance in forming an opinion upon the fact of kennel lameness being indigenous to certain situations, and shows most clearly how little benefit can be anticipated in those cases where the malady is severe, by the interposition of impervious concretes, asphaltum, and such like preparations.