3. Climate and Diseases. —The climate of Jerusalem, while bearing the broad character- istics common to the land, presents in some re- spects marked features of contrast to that of the Jordan Valley and other low-lying places which were the scenes of the ministry of Jesus. There is
* This V and has heen recentlj Samlay.
t Cf. BJ T. iv. 1, VI. vi. 3, and V. vii. 2
every reason for believing that the general climatic features are the same to-day as then. On tlie whole, Jerusalem must be considered healthy, and what disease there is, is largely due to preventable causes. The marked changes of season, the clear pure atmosphere, with frequent winds, and the cool nights even in midsunmier, combine to give Jeru- salem a climate superior to the lower parts of Palestine. In winter the cold is considerable but never extreme, the lowest temperature recorded in 20 years being only 25° F. As a rule, a frost occurs on some half a dozen nights in each year. January, February, and December are, in this order, the three coldest and wettest months, though the minimum temperature has occurred several times in March, and a night temperature as low as 40° at the end of May (cf . Jn 18"*). Snow falls heavily at times, but only in exceptionally severe winters. The average rainfall is about 26 inches, a lower mean than at Hebron, but higher than in the plains and the Jordan Valley. The maximum fall recorded (1847) was 41-62 inches, the minimum (1870) was 13-39. So low a fall as this, especially if preceded by a scanty fall, means considerable distress in the succeeding dry season. During the summer no rain falls, and the mean temperature steadily rises till August, when it reaches 73-6, though the days of maximum heat (near or even over 100°) are often in September. It is not, how- ever, the seasons of extreme lieat or cold that are most trying to the health, but the intermediate spring and autumn, especially the months of May and October. This is largely due to the winds. Of all the winds the most characteristic is the S.E. — the sirocco — which in midwinter blows piercingly cold, and in the spring and autumn (but not at ail in the summer) hot, stifling, and often laden with fine dust from the deserts whence it comes. On such days all Nature sutlers, the vege- tation droops, .and man not only feels debilitated and depressed, but is actually more lialjle to ill- ness, especially ' fever ' and ophthalmia. The N.W. is the cold refreshing wind which, almost every summer afternoon and evening, mitigates the heat. The S.W. wind blows moist off the sea, and in the later summer brings the welcome copi- ous clouds and, in consequence, the refreshing ' dews.' In the early mornings of September and October thick mists often fill the valleys till dis- persed by the rising sun. The onset of the rains, in late October, is not uncommonly signalized by heavy thunderstorms and sudden downpours of rain, which fill with raging and destructive floods the valleys still parched by seven months' drought. As much as 4 inches of rain has fallen in one day.
The diseases of Jerusalem are preventable to a large extent under proper sanitary conditions. Malarial fevers, ophthalmia, and smallpox (in epidemics) are the greatest scourges. Enteric fever, typhus, measles, scarlet fever, and cholera (rarely) occur in epidemics. Tubercular diseases, rheumatism, erysipelas, intestinal worms, and various skin diseases are all common.
i. Water supply.— The water supply of Jeru- salem has in all its history been of such import- ance and, on account of the altitude of the city, has involved so many elaborate works, which remain to-day as arclueological problems, that it will be well to consider it separately. The city never apjjears to ha\e seriously suttered from want of water in sieges, but probably at no period was Jerusalem more lavishly supplied with water than it was during the Roman predominance, and most of the arrangements were complete before the time of Christ.
Of springs we know of only one to-day, and there is no reason to believe there were ever any
JERUSALEM
.TERUSALEM
more. This spring is that known to the Chris- tians as 'Ain Sitti Miriam — the spring of the Lady- Mary — or the Virgin's Fountain (from a tradition that the Virgin washed the clothes of the infant Jesus there), to the Moslem fellahin a,s'Ain umm cd-deraj — ' the spring of the mother of tlie steps,' and to the eastern Jews as ' Aaron's {or ' the priests") bath.' The water arises in a small cave reached by 30 steps, some 25 feet underground, in the Kidron Valley, due south of the Temple area. Though to-day lying so deep, there are ample eridences that originally the mouth of the cave opened out on the side of the valley, and that tlie water flowed out thence. It has become buried through the accumulated debris in the valley bed. At the back of the cave — some 30 feet from the entrance — is a tunnel mouth, the beginning of the famous SLloam aqueduct (see SiLOAM). The flow is intermittent, about two or three times a day on an average. This fact is recorded by Jerome, and is by many authorities considered a reason for locating here the Pool of Bethesda (see Bethesd.\). The water is brackish to the taste, and chemical examination shows that, to-day at any rate, it is contaminated with sewage. It is undoubtedly unfit for drinking purposes : it is used chiefly by the people of the village of Sihcan, especially at the SUoam-pool end of the aqueduct, for watering their gardens.