Now it is remarked by travellers that the Egyptian dogs are almost in a state of inaction during the day; they lie down in the shade near vessels full of fresh water, prepared by the natives. They only run about in the night-time; they evince the signs and effects of their love but once a year, and only for a few moments. They ate seldom seen together or coupled. They do not go into the houses in the daytime; they remain at the sides of the streets, and wander into the country at night, in order to find any dead animals which happen to he unburied. Their disposition is meek and peaceable, and they rarely fight with each other. Possibly all these causes may exempt them from rabies.

Now this observation about the exemption of the Egyptian dogs from rabies is very ancient, having been made by Prosper Alpinus; and according to Barrow, the dogs in the vicinity of the Capo of Good Hope and in Caffraria very rarely go mad; while several writers assert that rabies never occurs in South America. Again, Valentin declares that it is exceedingly rare in the warm regions of America, but common in the northern part of that continent. Dr. Thomas, who resided a good while in the West Indies, never saw or heard of a case of rabies there; and Dr. B. Moseley states that the disorder was not known in those islands down to 1783. On the other hand, the disease sometimes happens in the East Indies, though not with such frequency as at all to justify the doctrine about heat being the cause of its production. The silence of Hippocrates proves that in his days hydrophobia must have been very rare in Greece. And as the disorder is not mentioned in the Scriptures, an inference may be made that it could not be common in the hot tracts of the globe inhabited by the Hebrews, as in the temperate climates of Europe and America.

Neither can the sentiment be received as correct that rabies is more frequent in the north than in the temperate parts of Europe, for De la Fontaine particularly notices how extremely rare it is in Poland. Again, the disease is reported to be very common in Prussian Lithuania; but mad dogs are seldom or never heard of at Archangel, Tobolsk, or in the country north of St. Petersburg.

In Mr. Meynell's account, which was communicated to him by a physician, it is asserted that the complaint never arises from hot weather or putrid provisions, nor from any cause except the bite; for however dogs have been confined, however fed, or whatever may have been the heat of the season, the disorder never commences without a possibility of tracing it to the preceding cause; nor was it ever introduced into the kennel except by the bite of a mad dog.

Dr. Gillman endeavours to prove that the disease in dogs is probably excited independently of particular climates, of putrid aliment, of deficiency of water, of want of perspiration, etc, and he expresses his belief that it originates somewhat like typhus in the human subject, and is not always produced by inoculation or by means of a bite. He thinks that it may be occasionally brought on by the close confinement of dogs, want of exercise, or close, filthy kennels, and that the success of Mr. Trevalyan, as related by Dr. Bardsley, in clearing his kennel of the disease by changing even the pavement, after other means of purification had failed, affords presumptive evidence in favour of the opinion; and, consequently, this author thinks that the method of quarantine adopted by Mr. Meynell and recommended by Dr. Bardsley, on the supposition that the disease originates exclusively from contagion, will not be a sufficient prevention alone; and he infers from some facts reported by Mr. Daniel that the poison sometimes lies dormant in dogs four, live, and six months, and, consequently, that the period of two months is not a sufficient quarantine. Now, in opposition, however, to some of the sentiments contained in the foregoing passage, it should be known also that Dupuytren, Magendie, and Breschet have purposely kept many dogs for a long time in the most disgusting state of uncleanliness. Aye, they have even allowed them to die in this condition for want of food and water, or even devour each other; yet, notwithstanding all this, they failed to excite rabies. And yet Professor Rossi of Turin is said to have produced this or some similar disease in cats by keeping them shut up in a room.

Therefore, on the whole, I consider it well proved that neither long thirst, hunger, eating putrid flesh, nor tilth, will occasion the disease in the canine race.

At Aleppo, whore these animals perish in great numbers from want of food and water and the heat of the cliinate, the distemper is said to bo unknown. Nor is rabies found to attack dogs and cats with particular frequency during the copulating season, and therefore the oestrus veneris cannot be admitted to have any share in its production, as some writers have been disposed to believe. Although most writers believe in the reality of a poison or specific infectious principle in cases of rabies, the fact has been questioned or absolutely rejected by others. In fact, Bosquillon considered the disease always as the effect of fear, or an impression upon the imagination. This view of the matter is far from being new, and has been ably refuted, because it will be difficult for us to imagine now that one could impress a terror of hydrophobia into a horse's, ass's, or mule's head; yet they die from rabies.

Another notion has partially prevailed, that rabies does not depend upon any virus, but upon the continuance of an irritation in the bitten parts affecting the whole nervous system. Bat this doctrine confounds rabies and locked-jaw together, and can only apply to the symptomatic non-infectious hydrophobia from an ordinary wound or laceration.

Now the facts in proof of the reality of a peculiar infectious principle in cases of rabies are too numerous to leave any doubt upon the subject Twenty-three individuals were bit one morning by a female wolf, of whom thirteen died in the course of a few months, besides several cows which had been injured by the same animal. How could all these unfortunate persons have had similar symptoms, and especially a horror of fluids, had they not been all under the influence of some cause besides the bites? The patients who died were bit on the naked skin, while in the others who escaped infection the bites happened through their clothes, which no doubt intercepted the saliva, the vehicle of the virus.