which its inundations have reached." Such being the startingpoint, should the wind prevalent in Greece and in the northern regions above it have a southerly tendency, this pestilential south wind would find no difficulty in blasting with its poisonous breath the inhabitants of the Mediterranean islands and their northern neighbours. Thucydides, as we have seen above, in his account of the plague at Athens, traces it in a south-west direction to Persia, and thence in a south-east one to the island of Lemnos, the Piræus, and Athens.

But we must not draw too hasty a conclusion with regard to the wind being the means of conveying epidemics from one country to another: although, combined with the presence of other causes of disease, it might be instrumental in bringing about a pestilential state of the atmosphere, yet, for the spread of the plague and other epidemics we must look to the communication that takes place between one nation and another for the most important means of propagation. On this subject Hecker* remarks, in reference to the great plague of 1348"The corruption of the atmosphere came from the east; but the disease itself came not on the wings of the wind, but was only excited and increased by the atmosphere where it had previously existed. This source of the black plague was not, however, the only one; for far more powerful than the excitement of the latent elements of the plague by atmospheric influences, was the effect of the contagion communicated from one people to another, on the great roads, and in the harbours of the Mediteranean. From China, the route of the caravans lay to the north of the Caspian Sea, through Central Asia to Tauris. Here ships were ready to take the produce of the East to Constantinople, the capital of commerce, and the medium of connection between Asia, Europe, and Africa. Other caravans went from India to Asia Minor, and touched at the cities south of the Caspian Sea; and lastly, from Bagdad through Arabia to Egypt; also, the maritime communication of the Red Sea, from India to Arabia

* Epid. Midd. Ages, Syd. Soc. ed. p. 19.

and Egypt, was not inconsiderable. In all these directions contagion made its way; and, doubtless, Constantinople and the harbours of Asia Minor are to be regarded as the foci of infection, whence it radiated to the most distant seaports and islands.

To return, however, to the south wind, we must consider it more as the cause or concomitant of warm mild weather, than as being pestilent in its very nature; and from this point of view must we study it. With the south wind, therefore, have we associated heat and moisture; the former of which, according to Galen, is the active, and the latter the material cause of putrefaction. Throughout the writings of the many distinguished physicians who published essays on the plague, sweating sickness, influenza (epidemic catarrh), &c., we find several valuable meteorological observations, which will be interesting in this place, and tend to show that however varied the symptoms and signs of an epidemic may be, yet there is a certain constancy in the appearance of certain atmospheric phenomena. I must again refer the student to the above Table, whilst I enumerate a few of the many remarkable facts recorded in the history of epidemics.

The first visitation of the Sweating Sickness in England was in the beginning of August 1485, the year in which Richard III., the last king of the Plantagenet dynasty, was slain in the battle of Bosworth, and the Earl of Richmond was proclaimed king as Henry VII. The years from 1480 to 1485 were wet years. This dreadful disease was swept away January 1st, 1486, by a south-east wind. The humidity of the year 1485 was remarkable, says Hecker, throughout the whole of Europe; the rain fell in torrents, and inundations were frequent. He observes that damp weather is not prejudicial to health, if it be merely temporary; but if the rain be excessive for a series of years, so that the ground is completely saturated, and the mists withdraw baneful exhalations out of the earth, man must necessarily suffer from the noxious state of the soil and atmosphere which, under

these circumstances, must inevitably follow.* The second visitation of the sweating sickness took place in 1506, which year was preceded by the wet summer of 1505, followed by a severe winter."

In 1510 the Influenza broke out, which, according to Dr. Short, had for its precursor "a long moist air." The appearance of this epidemic in 1557+ was after the prevalence of continued wet weather, of which the same author writes:— "1557.-This year and last was a great scarcity of corn from the past great rains. It was a very unseasonable year in England: all the corn was choked and blasted, the harvest excessively wet and rainy." There were also ill-smelling fogs at the time. In short, to quote the summary of Dr. Theophilus Thompson's compilation from the authors on Epidemical Catarrh, we find that the visitation of 1580 commenced in October, after a cold dry wind preceded by two or three years of “a moist, rainy, southerly constitution."

That of 1675, after a pungent fog and cold moist weather. In 1710 the Influenza reappeared, "during a moist southerly constitution."

In 1729, "after a rainy November with high tides.”

In 1732-3, "during a damp chilly spring, southerly, and fetid fog."

In 1737-8, the influenza commenced in November, when, Huxham says, "a southerly wind indeed damped the month." In 1743, "during the three months preceding the attack of influenza, the atmosphere was for the most part moist and damp, and a stinking fog in January." Dr. Millar observed, with regard to the epidemic of 1758, that "October was very cold and moist, and that a great quantity of rain fell.”

In 1762, Dr. Pretty observed that after the drought there were "great gluts of rain." The influenza of 1775 "prevailed during a wet autumn." In 1782 it appeared after the summer *Op. cit. p. 187.

The year in which Calais was taken by the French.

in 1781 having been very dry, the autumn very rainy, the spring of 1782 remarkably late, then gloomy, cold and humid, with occasional dry fogs and peculiar storms." During the epidemic of 1803, the three months February, March, and April, were for the most part cloudy, showery, foggy, and rainy. The epidemic of 1836-7 succeeded disastrous gales, the drifting of the snow, and the floods by the thaw. The year 1836 was remarkable for the number of days in which the south-west wind blew. The mean for the seventeen years from 1826 to 1842 inclusive was found by Daniell* to be 79.8 days, whereas, during this year, the number of days in which this wind prevailed was 126. The amount of rain for the same year was also above the average (24·16 inches); the quantity that fell at Chiswick when the observations were made being 28.73. In the following year, however, the rain was not so abundant, 19.88 inches only being registered: but the wind which prevailed was the south-west. From the above facts the reader will be able to draw his own inferences; and I think he will be satisfied that a southerly wind does seem to merit a great deal of the odium that the antient writers used to attach to it. The necessity of observing the constitution of previous years and seasons was well appreciated by the older physicians, who, from their more intimate acquaintance with the writings of the Fathers of Medicine, were led to adopt the judicious mode of observation which the writings of Hippocrates prove that he adopted.

Celsus wrote thus with regard to the weather of foregoing days: "Neque solum interest, quales dies sint, sed etiam quales antececesserint." The aphorism would hold equally good if we substitute anni for dies. The prevalence of the south-east wind was observed to be particularly favourable to the increase of Cholera and Influenza; and Dr. C. J. B. Williams

* Meteorological Essays, vol. ii. p. 339.

+ Celsi Med. lib. ii. cap. i. p. 36, Milligan.

Princip. Med. and Pract. of Medicine, p. 42, foot-note.

cannot

but think that this had some connection with the general tendency exhibited by the former to spread chiefly from east to west. He asks this question: "Has the morbific property of this wind aught to do with the haziness of air when it prevails,-a haziness seen in the country remote from smoke, and quite distinct from fog? What is this haze? In the West of England a hazy day in spring is called a blight." During the cholera epidemic of 1854, the south-westerly winds and calms prevailed, as will be seen from the following analysis. From the 28th week of the year (ending July 15th) to the 49th (ending December 9th) the deaths from cholera rose from five in the week until they amounted to the maximum during the 36th, after which they gradually declined until they again were reduced to five in the 49th week: within this period 22 weeks are included, during fourteen of which the south-west prevailed: the remainder were characterised thus:-one, east-north-east; one, north-west and south-west; two, north-east; three, variable; and one, north-east and south-west. Out of these twenty-two weeks, there were twelve in which calms prevailed, and during many of the rest there were several calm nights and days.

The Calm that prevailed throughout this pestilential constitution is another characteristic: ἄπνοια διὰ τέλεος-there was a calm throughout observed Hippocrates. This absence of wind has been observed during the prevalence of cholera. Mr. Hingeston, in his highly interesting papers, in the Association Medical Journal, lays stress upon the fatal calm that reigned during the visitation of the cholera in 1832. Conjoined with this fearful atmospheric stillness was that seemingly interminable moistness that was suspended for such a length of time over our ill-fated island. Even the most indifferent observer could not help remarking how gloomy and cloudy the weather was, a state of the air that was either associated with or dependent upon the calm. Hippocrates observed the same phenomena, and noted them down in his description of this pestilential year (φθννόπωρον σκιώδες, ἐπινέφελον). Amongst many other remarks,