Two ideas appear to me essential in treating yellow fever; the fever must be diminished, and the essential poison of the disease neutralised. Two safe and apt remedies are at hand - purgatives and quinine, usable together, and not opposed - regarding the disease in this light.

Vomitives are very seldom necessary or advisable in this disease; the tendency to vomit is generally to be repressed. But if there are evidences of stomach oppression, and quite in the early period of this disease, the remedy is certainly useful. In the early period purgatives are absolutely indispensable; there is always constipation and fever, and they must be pushed until the fever abates.

The distressing headache is signally relieved by pediluvia of hot water and mustard, followed by the employment, constantly, of an evaporating lotion. The pain in the back is alleviable by sinapisms, and this and the general aching of the frame by the use of stimulating liniments.

Mercury is useful as a purgative and alterant of the secretions of the bowels; its constitutional action has seemed to me quite disadvantageous. Of course we have never employed general bleeding; I have cupped over the loins in urinary suppression, but without advantage; leech-bites give trouble when the second stage comes on, from the exudation of blood.

During my attendance at the lazaretto I was able to appreciate the marvellous results in restraining hæmorrhage of the ergot of rye. Given in doses of the powder of five grains every hour, or in pills, it controls most perfectly the hæmorrhages, and even the black vomit. I have not seen this remedy mentioned in any treatise on yellow fever. It is most valuable, and its employment a true advance in the treatment of the disease.

Baths of all kinds gave me no results; nevertheless, hot hip-baths in the urinary suppression should always be tried. The wet sheet was often agreeable to the patient, but it did not answer my expectations in the general result. The cold douche in the lethargic state also disappointed me.

Quinine was administered by an empirio in clysters, and, if we bear in mind that the autopsies showed the large intestine to be unaffected, are theoretically correct. However, as I never employed solutions of quinine, the stomach nearly invariably tolerated the remedy. My plan was to give ten grains of quinine, made into four pills, with extract of gentian every night and morning, at intervals of twelve hours between each dose, employing neutral saline purgatives between times, and combating symptoms as they arose.

Vomiting was often very difficult to allay. Chloric ether succeeded best, and ergot if there was black vomit. Hiccough was often most troublesome, and generally of fatal augury. Opium controlled it best in full doses. The gastric oppression was somewhat relieved by the use of poultices of linseadmeal and mustard. The urinary suppression was the intractable and fatal symptom. In one of my cases black vomit ceased, and the urine returned, after two days of absence, during the use of ergot of rye. I have heard it has also returned during that of nux vomica, and also of phosphorised glycerine. Perchloride of iron failed, to my knowledge, in producing it. Acetate of lead and opium in pills were spoken well of in the hæmorrhages. I never found the ergot to fail, if it were good, and so was satisfied with it. I believe chlorine solutions and carbolic acid were employed internally; I do not know with any specially good result. The digestive functions were naturally sufficiently impaired, and great care was necessary with diet during convalescence. At first, in the early part of the disease, an absolute diet seemed best, and plain barley-water the most suitable beverage. I have said that yellowness of the conjunctivæ was an early symptom. It seemed to me the earliest most reliable sign; the next albuminaria.

Gastric irritability was very marked. Palpation of the epigastrium so easily produced vomiting, that it was always well avoided. I believe that when quinine has been previously used in the treatment of "specific" yellow fever, it has been used too exclusively. If the stomach evidently requires unloading, it must be unloaded - just as you would unload it in a tropical fever, if it were indicated - before you give quinine. The same holds good of purging, with this advertence, that as yellow fever is a rapid disease you cannot wait until you have entirely subdued the feverishness before administering the quinine, but must be content to begin when you observe you have made an impression by your evacuant plan. As you can cure malarious fevers without quinine, so may you cure yellow fever of the specific type without it. The Paraguayans cure their milder paludals with such simple treatment as would be adopted in a common cold - in fact, they call their milder paludals colds. But just as a tropical fever is pernicious, so is quinine valuable.

There is a question as to how far all these fevers are the product of meteorological, topographical, or geological conditions, and whether they are merely expressions of the effect of climactic or weather peculiarities, or depend on some special terrestrial emanation, or are due to local meteorological influence on vegetable and animal decomposition; and so to what relation typhus and typhoid fevers bear to the severe tropical fevers; and as to the action of quinine, whether antiseptic or neurostenic. Fevers being diseases which affect the whole system, naturally will require numerous remedies; and where the nervous implication is the eloquent and serious expression, neurostenics claim a first place. I enclose extracts from the Buenos Ayres Medico-Chirurgical Review:-

"February 8,- In the early part of the present fortnight information was given by Dr. Larrosa that in Bolivar-street there had arisen some cases of yellow fever, due, doubtless, to the special pathological constitution, to the indifferent hygiene of the houses, and to the great heat of the weather. The Municipal Council of Health caused the house to be disoccupied immediately, burnt some of the furniture, and disinfected the remainder and the house itself. The disease does not seem to have made much progress, and appears to be stationery in the district where it began.

"February 23,- The small epidemic of yellow fever diminishes notably in the district where it began, although a few cases present themselves in the northern and western districts of the city. The connexion of the cases (of many of them) in the other districts with those in the parish first infected has been clearly proved. However, some cases do not show any such connexion, so we keep a prudent reserve about the future of the epidemic. The fact of many being saved in this epidemic, and the spirit of contradiction which exists in all, has caused that some have denied that yellow fever exists, but it is not the less certain on this account, and has made somewhat more than 200 victims. The fever contracted in assisting the sick has carried off one of the most notable Medical men of the Republic.

"March 8,- Yellow fever has much increased, particularly in houses where many persons are congregated together, especially amongst Italian emigrants. 800 have died of the fever in the last fortnight, the Italians in a proportion of 70 per cent. of the deaths The Nacion newspaper has commenced the crusade against the Riachuelo, our little Ganges - a focus of corruption which infected the atmosphere with miasmas favouring and feeding the development of diverse epidemics.

"March 23,- This fortnight's review offers us a very unconsoling picture. Now it is not only in certain districts that the fever exists. Without much difficulty, it has advanced until it has dominated completely the population, and its victims have fallen by hundreds daily. The atmosphere we breath is completely infected. The daily statistics are very incomplete.

"April 8,- In the past fortnight the epidemic has been general; the whole of this extensive city is invaded, The funeral cortéges pass constantly through the streets. The exodus to the country is considerable. During certain hours of the day, and principally at nightfall, the closed doors and solitude of the streets give this great city a mournful and sepulchral appearance. There have been days in this fortnight when the number of deaths from the fever has amounted to 700.

"April 23,- The yellow fever has acquired colossal proportions, and has taken possession of all quarters of the city. All the well-to-do families take the efficacious precaution to leave for the country. We should further this emigration amongst all classes of society by all possible means.

"May 8,- The sanitary state of the city is more agreeable this fortnight, for the epidemic beats its retreat notably. Thirteen worthy and ever-to-be-remembered colleagues have succumbed to the cruel influence of the epidemic now disappearing.

"May 23,- The epidemic undoubtedly bids us farewell, since. in spite of the large number who return from the country, the death-rate does not increase, and there are very few more cases."

Dr. Aguirre, writing in the Review of March 23, says:- "We have yielded to the temptation to make some experiments with the sulphate of quinine, and repentantly have we recognised with how much truth others have previously had prescribed it, for given in the first period it does not abate the inflamatory symptoms, but increases the agitation and anxiety; given later and in larger doses, it produces a hypostinisation which predisposes to irremediable adynemia."

Dr. Sturrios, writing in the Review of May 23, says:- "We give a singular case of yellow fever. A patient, who had passed through all the stages of the disease, amd was still in the third, presenting hæmorrhage from the mouth and much epigastric anxiety, suddenly one night was seized by tonic contractions of the muscles of relational life (voluntary meant), accompanied by pains and parodying tetanic convulsions. The first fit lasted six hours, causing the patient to suffer cruelly. On the following day the attack repeated itself, almost at the same hour, threatening seriously the life of the patient, for the contraction of the muscles of the chest rose to such a point that the agony of asphyxia appeared imminent. This attack lasted four hours. A third access repeated itself the third day, and was like the second; it lasted three hours. The fourth and last fit was very short and mild. Quinine was given as an antiperiodic until cinchonisation was obtained, it being then that the attacks disappeared; chloral and syrup of belladonna were used at the same time."

Dr. Reynal, parochial Medical Officer of the Piedad District, wrote to the Republica newspaper in April, stating that he had only lost ten patients out of 140 in using quinine in solution in large doses. He states as follows:-

"Computing the number of patients treated by a general method with those who have been saved thereby, I did not hesitate to abandon such plan, and adopt as basis of my treatment the sulphate of quinine. In a few days the result justified my resolution, since I found that, of 140 patients to whom the remedy had been given in the first period, and many in the second period, I lost only ten, and even those not in spite of the quinine, but on account of it being badly given. I continue employing it, and with the same result. I do not make any pretension to offer this as a novelty, nor still, as an infallible remedy, but as being more certain and based upon analogy, facts, experience, and judgement. My plan of administration is as follows:- Sulphate of quinine grs. xxx., water ziv., citron-water zj. Of this I give two tablespoonfuls every two hours until cinchonisation supervenes. I only precede this administration of the remedy by a vomitive or purgative if there are manifest signs of gastric and intestinal embarrassment; and when such signs are wanting, as is usual in the invasion period, I do not lose time, but give the quinine immediately. Four-and-twenty hours do not pass before the cinchonism manifests itself, and in a few hours the headache is replaced by heaviness, the fever ceases, and there only remains the prostration consequent upon the medication and the battle between the system and the disease. In mild cases, a vomitive, a purgative, sudorifics, or even the sole powers of the constitution itself, are sufficient; but, at first, who can anticipate a benign disease, and say, so far and no more shall be the fatal essence of the miasma reach? So I do not hesitate, but to all, without exception, give quinine, harmonising the dose with the pronunciation of the fever. The results obtained authorise me to recommend quinine as almost infallible in the first period, doubtful in the second, and entirely useless in the third."

I prefer to give quinine in pills and obtained my object by exhibiting it in such form. The stomach is so affected in the disease that it should hardly tolerate such a nauseous bitter draught as a solution of quinine. As I constantly gave purgatives, I did not employ quinine in enemas, as I have said such treatment was pursued by an empiric who had seen this method adopted in countries where yellow fever is endemic. I believe pretty good results followed this person's treatment.

It seemed to me that the contagiousness of the fever might be assumed to be a local infectiousness, existing in the place where a patient lay. The importation of the disease seems certain. Albumen generally existed in the urine, and suppression of that secretion was a frequent and almost invariably fatal symptom.

The origin of the term "mal de Siam" for this disease is thus accounted for by the Siglo Medico, a Spanish Medical journal:- 'That at the end of the seventeenth century three vessels (one called the Oriflamme) arrived at Martinique from Siam, and that coincidentally with the arrival of these ships a disease, of a severity unknown previously, sprang up. But it asks the question - "Did the ships bring the disease with them or get it in this port?" The matter has been explained by averring that the Oriflamme previously touched at a Brazilian port, and there took the disease on board. But the writer of the article referred to says this is not proved, and believes that the arrival of unacclimatised persons at the Antilles in these ships was the determining cause of the appearance of the disease. It is well to be in mind that Martinique and Siam occupy analogous latitudes in the different hemispheres, and that any disease brought by the vessels probably might have encountered favourable conditions for its development, and yet it may not have differed so much from any endemic disease, except in the element of deadliness; and really causes it to merit such distinction politically.

The Medical Officer of the port of Monte Video made his public statement at the commencement of the epidemic, that the epidemic must be a bilious remittent on account of a similar announcement by a Brazilian Medical man who wrote from Asuncion, Paraguay, to that effect, and, I believe, based his opinion on the beneficial results which followed antiperiodic treatment, to the efficacy of which Dr. Newkirk, a Canadian living in Asuncion, gave me his personal testimony afterwards.

In Corrientes the same phenomena were observed as here; a large part of the population fled, and of those who remained a great proportion died, one-fourth of the population remaining. The poverty in which so many working families will be plunged by the loss of their chief supports must naturally be very great, and the number of orphans to provide for be very large. The neighbouring republics of Chili and the Banda Oriental have come splendidly to the help of the desolated city, as also has the Empire of Brazil. Since men suffered to a much larger extent than women, and both than the younger members of families, it is natural to anticipate distress of a considerable amount in consequence of the epidemic; fortunately, our winters are not of the severe northern type; frosts are neither frequent nor severe, and snow unknown.

The epidemic of this year does not seem to be in the least connected with the few cases that occurred in one establishment during the summer - or rather, the autumn - of the previous year. That outbreak appeared to extinguish itself in the locale where it sprang up; it was notoriously imported from Rio Janeiro. The epidemic was notified this year as springing up in an opposite quarter of the city. There is also no doubt that the first yellow fever appearing in Paraguay, twelve months before the great outbreak, was connected with Brazil. Where did the Rio epidemic of 1869-70 arise?

The winter temperatures in Buenos Ayres should be an extinguisher to the yellow fever poison, and, it is to be hoped, will prove such, as it has done previously. Buenos Ayres is favourable enough for epidemics from its insanitary conditions, but it is probably not worse than most New-World cities, where sanitary progress is generally the last point thought of.