style="font-size:15px;"> FIRST PART
The History of the Contagious Typhus of the Ox, from the remotest times down to the present day.
General, local, and particular causes of destruction are constantly reacting on organized creatures, and these causes account for those epiphytic diseases which infest plants, the epizootic diseases which spread mortality among the brute creation, and the epidemic, which strike and are fatal to the human species. Thus it is that we particularize at present, in the vegetable kingdom, the disease which has attacked the vines, olive-trees, and potatoes; in the animal kingdom, the silkworm sickness, and the cholera, and the typhoid fever of cattle: so that we may safely say, that one or other of these diseases is always, at a given moment, raging in some part of the globe among some species of animal, either birds, pigs, horses, sheep, horned cattle, or, in fine, attacks man himself.
When, however, the peccant invasion falls only on the vegetables and animals situated at our antipodes, we seldom hear of the ravages it commits; and when we do, forgetful of the affinity which links together all the organic beings on the earth and their mutual dependence, nothing can exceed the indifference we show to these calamities. Then, when the danger threatens us nearer home, or when the evil has invaded us, we have recourse to quarantine as the grand preservative to shield us. But this preservative remedy is most frequently deceptive – a mere illusion; for the real plague, typhus and cholera, borne along by the winds of heaven, pass over the longest distances and the highest obstacles, and baffle all our calculations; teaching us, by their successive returns, that we shall continually be exposed to their destructive havoc so long as we neglect to eradicate the evil at its original source, that is, in those countries from which it emanates.
And this is the place to observe, that the cholera morbus threatens to keep a permanent footing in the English possessions of India, because the public works, by means of which the great rivers used to be confined to their beds, have not of late been repaired and kept in good order in those countries; owing to which neglect, their waters overflow the plains, leaving, when they subside, those pestilential deposits which afford a perpetual incubation to the cholera.
We are induced to dwell thus on the general causes of these diseases, because the sick plants, on which dumb animals feed, and the sick animals, on which man himself feeds, have a continual relation of cause and effect; and we shall have to refer to this subject and give it weight, when we come to speak of the treatment of these diseases.
It is an important fact, which deserves our most pointed attention and consideration, that the vital resistance inherent in the animal frame to withstand the attacks of these contagious diseases, is very far from being the same throughout the whole kind. Man, in this respect, is the most favoured and best fortified; he is able, without much degenerating, to inhabit any latitude, to go with a sort of impunity, if his calling require him to do so, amidst the most pestilential emanations, and to continue for hours inhaling their baneful fumes. We could quote many striking examples of this resisting power in man. But there is one which we have recently witnessed, and which all can appreciate. We refer to the slaughter-house of the great Metropolitan Market. Here we saw, in lumps and fragments, every variety of corrupt detritus of animals which had been seized with the contagious typhus; we saw the animals, too, being felled and slaughtered and dissected, in a high temperature which rendered the air so poisonous that we could hardly breathe it; yet amidst all this infection the workmen employed to move and handle these revolting wrecks appeared indifferent to the scene, and quite in their usual health. No living animal besides man could stand such a trial; no other could breathe for hours, and day after day, like these workmen, an atmosphere so charged with decomposing impurities.
We say, therefore, that man may expose himself, with less danger to his life than any other animal, to those pernicious causes which produce and develop contagious diseases. Next to him, with respect to this power of vital resistance, come the omnivorous animals, then the carnivorous, and last of all, the herbivorous, in which this faculty is very feeble indeed.
This prime consideration, to be fully understood and appreciated by unscientific readers, would require explanations beyond the scope of this work. Let us, however, for the present establish the fact, that herbivorous animals, such as sheep and horned cattle, offer but a very weak resistance to the causes which generate infectious and epizootic diseases, and let us do our best to prove it by demonstration; for if this truth be once admitted, we shall therefrom deduce that it is the duty of man constantly to surround these frail and delicate creatures with special care and attention, if he wishes to prevent their being decimated from time to time, and if he would likewise avoid the consequent injuries to himself – the loss of health and money accruing from this deterioration.
So long as the herbivorous or grass-eating animal is properly fed; so long as he browses on fat pastures; so long as his blood retains those physiological elements which are the prime condition of health, he can, and does, resist the causes of most contagious maladies. But if a hot summer and a long continuance of dry weather chance to curtail, in temperate zones, the usual abundance of his fodder, then comes the fatal change: the blood is impoverished, the secretions are debilitated, a strange languor runs through the system, the vital resistance is unnerved, and he becomes an easy prey to those noxious influences which were encountered before without injury whilst his provision was abundant.
This is a fundamental matter. We therefore beg leave to support and justify our argument by borrowing some additional evidence from prior labours of ours, accomplished at the Ecole d'Alfort, near Paris, conjointly with Professor Delafond, whose name has so often been cited in the public journals in connexion with the cattle plague.
All vegetables and animals; with the exception of adult men, whenever their health declines from any cause (but more particularly from paucity of food), spontaneously generate microscopic parasites, or very minute insects, the germs of which are inherent in their system. A flock of fleecy animals, wasted by deficient food in dry and parched meadows, becomes attacked in due time by a parasitical cutaneous disease, known as the itch, which is enough, if not checked, to destroy the whole. Now, all that is required is to remove this flock to a more fertile soil, where there is plenty to feed them, and the disease will disappear of itself without any treatment. Deficiency of food destroys the health of animals, and abundance of food overcomes disease in them.
A sheep affected by this parasitical disease may, without any fear, be placed in a flock of healthy sheep, for he will not propagate the distemper; but if instead of being sound and healthy, the flock is in a weak declining state, this contaminated animal will diffuse the disease with frightful rapidity, and may cause their entire destruction. These facts may seem startling, but we are only speaking after the incontestable authority of experiments.
We selected six healthy sheep, which we kept well supplied with provisions; we covered these healthy sheep with parasites (acari). On every one of these sound, well-fed sheep, the microscopic animalculæ died off without generating the cutaneous disease; for the blood, the humours, and the skin of sound and healthy sheep constitute a soil unfavourable to the propagation of these parasites, and actually starve them to death.
After this first experiment, we subjected these six sheep to a deficient diet; they grew lean, their blood was impoverished, and then all we had to do was to lay upon them not thousands and thousands of these parasites – as we had done in the first instance – but one solitary female in a state of fecundity; and the parasitical distemper unfolded itself so fiercely as to cause the death of three of these sheep on which the test was allowed to run its course; whilst the other three sheep, having been restored in time to a recoverable condition just as they were about to drop off, were thoroughly cured, without any special treatment, by the sole influence of good food and ordinary hygienic attention.
Other tests, similar to these experiments, were applied to dogs, horses, and horned cattle. A lean and scraggy dog, covered with parasites and eruptions, with eyes running foul humour, a dog which could neither
