§ 2. As no sane person doubts the harmony which can be shown to exist in all created beings, so it is probable, if not quite certain, that the laws of decomposition must be as regular as the laws of composition; or, in other words, that as the organic matter is without a doubt the same throughout the living world, and as living bodies are built up or constructed agreeably to certain laws, so, undoubtedly, will they be decomposed by laws equally fixed and constant; invariable; and the nature of the material so decomposed will in no shape be affected by those specific differences which bestow on organic nature her beauteous and varied aspect. § 3. The final product, whether of composition or decomposition, must be the same in all respectively; the infusoria, as well as the gigantic whale and elephant, are composed, when living, of the same elementary tissues, and, when dead, decompose into elements the same in all. § 4. The presence of microscopic animalcules in putrifying substances is viewed by Liebig as accidental, and not essential to putrefaction or to fermentation; but even admitting this, it is certain that animalcules (infusoria) exist everywhere in inconceivable numbers; if water contains these putrescible substances, as it must always do, then the infusoria are also present in the water; let this water evaporate under the heat of the sun, and we have in a fermentable, that is, putrescible, condition countless myriads of infusoria wafted through the atmosphere, and in certain localities (Pontine Marshes, Sierra Leone, the Orinoco, &c.) forming almost a constant, if not a constituent, part of the atmosphere; they pass into living bodies by respiration: hence the hitherto inexplicable phenomena with regard to the influence of locality in the production of disease, whether derived from animal or vegetable remains. § 5. Thus these bodies cause disease, not as live matter, but as dead, fermentable, and putrescible. They are not found everywhere, nor are they everywhere liable to pass into fermentation, a certain degree of heat being necessary for the production of this condition. Their evil effects on human life are chiefly felt when man places himself in a false position in regard to them. In pursuit of gain, national or individual, he seeks the deltas of the rivers of hot climates, plunges within the tropics, despising the maxims of the natives of those countries, encamps on or near putrescent marshes, hoping to escape destruction; prances in holiday costume across the Dobrudscha, as if he were on the Champs Elysées or the grassy slopes of Hyde Park, and having carried folly and contempt for the experience of others to its height, pays the sad penalty sure to be exacted by nature from all those who despise her warnings. These are my opinions, supported, I believe, by facts and figures, and to those who honour me with a perusal of the preceding chapters I beg leave to say, in the words of the ancient poet and satirist--