Climate and Health in Hot Countries and the Outlines of Tropical Climatology / A Popular Treatise on Personal Hygiene in the Hotter Parts of the World, and on the Climates That Will Be Met Within Them.

by George Michael James Giles

India and Ceylon.

—If we draw a line from Karachi, at the mouth of the Indus, to those of the Hughli, a little south of Calcutta, it will be found that we have divided the irregular diamond-formed outline of the country into two triangles, the upper or northern of which may be called the continental, and the lower the peninsular triangle. We also find that the dividing line coincides pretty accurately with the Tropic of Cancer, and that, therefore, all to the north of it is sub-tropical, while in the southern triangle there is, as one travels south, an increasingly marked tendency to a duplication of the rainy season and of weather conditions generally, with a resulting general uniformity of climate throughout the year, while the proximity of the sea ensures that the daily range of temperature will be also small. North of this, therefore, there is a distinct “cold weather,” while to the south this pleasant climatic interlude can scarcely be said to exist. One of my predecessors, writing at the end of the eighteenth century, in the course of some 300 very sober pages devoted to life and habits in India, perpetrated “with deeficulty” a single joke. He devotes a table of some six lines to the elucidation of the subject of climate, the columns being headed, Hot—Cold—Rainy Seasons. Opposite Madras the first column stated, “Begins January 1, ends December 31.” From his ill-concealed contempt of Madras and Bombay “presidencies” I am sure this old “Qui hai” hailed from “the Bengal side,” but, prejudice apart, there is a good deal of truth in the impeachment.

Taking first the northern or sub-tropical triangle, we find that it presents a much greater variety of climate than can be found to the south, for while its north-western side is intensely dry and arid, the eastern angle of the triangle contains the wettest spot in the world. This triangle includes, too, within its boundaries another “record,” viz., that for extreme heat. The man who “sent back for his blankets” resided, I believe during life, somewhere in the United States; but I fear he must have been a person of comparatively small endurance, as in the entire American continent there is no spot that in the matter of heat is in the same field with Jacobabad, where 127° F. (52·8° C.) in the shade has actually been registered, and, in fact, the whole of Scind easily “licks creation” in this unenviable detail.

The northern triangle may be divided into three distinct climatic regions, viz.:—

(1) The Persian frontier zone, including the Punjab, Scind and Rajputana.

(2) The Old North-west zone, containing Oudh, Rohilkhand, Benares, &c., Behar, and a good deal of Central India.

(3) Lower Bengal, including Assam.

It must not, of course, be imagined that there is any distinct line of demarcation between these “zones,” as each climate, of course, shades off gradually into the next, but this division greatly facilitates description.

The Persian frontier zone, especially in its western portion, closely resembles Persia in climate, and gives one a very good notion of what that country would be, were it not an elevated plateau. Excluding, of course, from consideration the Himalayas and Suleiman Range, its highest part, near Rawal Pindi, is only about 1,700 feet above the sea (E.M., 530), which is too little to sensibly modify the temperature.

Along the actual north-west frontier, the rainfall is very small and the summer heat intense. The daily range is very small at the worst time of the year, as the arid soil gets so baked during the day that it is able to give out an ample supply of heat to make the short night intolerable, without having time to cool down to any appreciable extent. The few scanty showers that occur relieve matters for a few hours only, after which the only trace of their passage is an increased dampness of the air, with the concomitant exacerbation of “prickly heat.” In certain places situated in some of the confined valleys that are to be found at the foot of the Suleiman Range, the heat, day and night, is perfectly appalling. Unfortunately, some of these choice localities are of administrative importance, as affording the best alignment for our railways, and their continuous occupation by a number of unfortunate European officials and by a native staff little better able to bear it, is an unfortunate necessity.