Cholera has no well marked periods or stages; but even if they could be defined, this would have no sort of practical value in the more intense degrees of the disease. Nevertheless, authors have thought proper to lay down certain stages, and we will follow their example.

First stage; stage of the invasion, precursory stage. In the more violent degrees of cholera this stage is scarcely, if ever, perceived; it sometimes lasts only a few minutes. In the milder forms of cholera, the invasion is characterized more or less by the following symptoms: About twenty minutes, and in very rare cases some days, previous to the outbreak of the disease, the patient complains of a general malaise, without considering himself sick; he feels debilitated, and exertions fatigue him extremely; there is an alteration in the expression of countenance, the patient looks anxious, sad, apprehensive, and a complete disfiguration of the countenance (the facies cholerica) soon follows. The patient is out of humour, restless, he moans, has an aversion to anything, especially to food and drink, complains of a disagreeable sensation of pressure, tension, creeping or rumbling in the stomach and bowels, without experiencing any real pain, sometimes accompanied with frequent eructations and slight nausea. The pulse is not much changed, but upon the appearance of the second stage it becomes more rapid, and withal smaller and weaker. The skin feels dry and cool, portions of the skin being covered with a slight, clammy sweat. The abdomen is generally tense, bloated, as if too full, but scarcely ever painful to pressure. In some cases the region of the stomach is somewhat sensitive, and there is some disposition to go to stool. Sometimes the patient complains of pressure in the chest, laboured breathing, a beating sensation in the chest, alternate chilliness and heat. The urine is more scanty than usual, and is either pale and clear as in spasms, or else turbid and cloudy. The head is generally without pain, but somewhat dull, heavy, and at times even giddy. Sleep is restless, frequently interrupted by starting and jactitation of the limbs. Those symptoms have degrees of intensity. The first stage may last from twenty minutes to twelve, fifteen, or even eighteen hours.

Second stage; stage of development. The symptoms which characterize the second stage vary, like those of the first, both as regards intensity and duration. In some cases the principal symptoms set in at once, increasing steadily until death has taken place; the first and third stage apparently do not set in. In other cases the symptoms increase more progressively and slowly, sometimes they seem even to remain stationary, and the patient improves, or, at any rate, seems to improve. This improvement, whether real or apparent, soon gives way to a new and so much more violently increasing aggravation, which may be considered the third stage. Some practitioners have observed, that the degrees of violence occurring in the second stage depend principally upon the nature of the locality where the epidemic prevails. This observation may be of importance in the treatment.

The second stage is generally characterized by the following symptoms: sudden vomiting, sometimes preceded by short nausea, but very seldom by real vomiturition; the food, which happens to be in the stomach, solid or liquid, is thrown up with a sudden jerk; after the first vomiting the patient sometimes feels a certain relief. Either simultaneously or a few minutes after the vomiting, diarrhoea sets in; this is papescent and partially liquid, the first three or four diarrhoeic stools being intermixed with faeces and half feculent, undigested food, slime and a watery fluid, accompanied with rumbling in the bowels, sometimes with pinching "and real colic, which is very seldom violent, and sometimes entirely wanting. The vomiting very soon returns, the diarrhoea likewise, the substances which are evacuated both by the mouth and rectum becoming more and more fluid, and quite watery. In many cases both kinds of evacuations are so frequent that the patient is scarcely able to rise from the chair; sometimes the debility is so excessive that the patient is unable to leave his bed, and has to be assisted in bed every fifteen minutes or more frequently, the average number of stools in twenty-four hours being from thirty to forty, together with as many vomitings. It is considered a symptom of the worst kind, and of approaching dissolution, if the diarrhoeic stools diminish in number while the strength of the patient and the pulse decrease proportionately. Generally speaking the number of the evacuations by the bowels or mouth varies; sometimes the evacuations are more numerous than in sporadic cholera, sometimes, and this is the more frequent, they are less in number; there have been cases of Asiatic cholera where only a few extremely copious and watery evacuations took place in the very commencement of the attack, occasioning excessive prostration.

After the second, third or fourth evacuation all succeeding evacuations are watery, or of the consistence and nature of an albuminous serum, or a serous mucus, or like rice-water; generally they are clear or somewhat whitish, inodorous and tasteless, with albuminous, cheesy, blackish flocks, floating in the midst of the liquid. As a general rule the abdomen caves in after the first diarrhoea; the whole body, in fact, sinks and becomes emaciated after the evacuations have continued one or two hours. This alteration is especially visible in the countenance. It is remarkable that there should not be any bile either in the evacuations upward or downward; even after death no trace of bile can be discovered in the intestinal canal. The want of bile is a characteristic phenomenon in the Asiatic cholera; not till the disease is on the decrease and an improvement sets in, do we perceive a tinge of bile in the alvine evacuations. These evacuations; which become painless as they continue, and finally take place without any sensation, are accompanied with a sense of exhaustion increasing to utter prostration. Restless and anxious, the patient is all the time endeavouring to change his position, even if he should faint in the effort. Shortly after, slight twitchings of the muscles, or only a drawing and tension in the muscles of the upper and lower limbs, sometimes make their appearance; sometimes these twitchings amount to violent and continuous spasms in the limbs, which are extremely painful, and are characteristic phenomena in cholera. These spasms first commence in the toss, fingers and hands; afterwards in the calves, etc. Sometimes the spasms are tonic or tetanic, in which case they are the most painful, and make the limbs immoveable, and stiff and hard as wood; generally the spasms assume the form of chronic convulsions. The spasms affect most frequently the calves, forearms and hands.