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the east or south-east. Budukhshan, Durwaz, and Keerategin Budukhshan are more humid than Cabul, as is Kushmeer. The humidity of Kushmeer adapts it for the production of rice, which however is there raised chiefly by artificial watering, and ripens in the drier part of the year. The dry and sunny summer of Cabul is favorable to the delicate fruits of the cold and temperate climates, which are here cultivated to a great extent and with much success, but in Kushmeer the apple only can be commended. Within the limits of India there is no place perhaps where less rain falls, and that little so irregular, as the neighbourhood of Mooltan. This however is little regarded by the farmer, who waters his khuruf crop from wells or canals drawn from the river, and raises a proportion of his rubbee on the moist lands which in the cold season the river has abandoned. Nor does the scantiness of the rains imply a dry air. Mists have been already mentioned as common there in the winter.
77. Having now mentioned in succession the altitudes of the mountains, and their course, the slope and conformation of the land, the sources of the rivers, the heat of the climates, and the periods and quantities of the rains and snow, we may proceed to deduce from these facts in combination the periods of the rising and falling of the streams and rivers. Few considerations are more important to the farmer and the traveller, or to armies.
78. In perfect plains in a warm climate we rarely find constant streams to originate. The rains of such countries though copious, are violent and of short duration. During the greater part of the year no moisture falls. The rains of the rainy season are drained off with a rapidity corresponding to their violence and their short duration. In their passage they cut deep channels which are dry during other parts of the year; such are very numerous in India, and are by us called dry nullahs. After rain they are always inconvenient to travellers, sometimes dangerous. Where they afford a level higher than the neighbouring ground under tillage, they are not without their use in agriculture, for by a little pains the water they discharge may be turned upon the fields. The Afghans are very sensible of their value, and reckon lands situated so as to be watered from them next to those which can be watered from constant streams, and superior to such as receive no water but what falls on their own surface. A dry nullah is in Pushtoo called ' Khevur,' and in the Hindhee of Peshawur and the west of the Punjab, Kus.' Even low hills in a warm climate usually give out but temporary streams. The snow which may fall on them soon melts, and the
springs which are found in them do not generally give out water. It is therefore plain that the periods of such streams as may originate in them must be the same as those of the rains and snows of the country; such are often of the greatest importance to the husbandry of a little neighbourhood, but their fame does not pass beyond those bounds. The Swan and Huro alone of this class are deserving of mention. They seem to have no periods distinct from the rains in the country, but their springs are sufficient to preserve them running streams at all seasons until they gain the Indus, whereas most others lose themselves, or are expended on the fields, in all seasons but the rainy, and some do not in any season reach the sea or a river.
79. We every day hear of mountains so lofty as to be covered with never melting snow. The expression construed in strictness would lead to an erroneous conclusion, for, that ice or snow can only remain unmelted which lies in a place whose temperature is never above the freezing point, and few such can be found within the habitable climates. Snow gradually disappears even during a hard frost. Part it is true, is carried off by evaporation, but part also is melted by the heat of the earth. The rivers of Switzerland rise from under glaciers of solid ice. As the inferior snows are gradually melted away, part of the upper also deprived of this support, either gradually slide down the declivities, or fall in avalanches, themselves to be melted in lower and warmer regions. The snow and ice are therefore perennial only because they are supplied from time to time as fast as they are consumed. It is also evident from the same principles, that the fall of snow in winter must in all cases have some tendency to augment the streams, since part is forthwith melted by the heat of the earth. But where these streams originate in hills of considerable altitudes, a far greater part is as it were stored up for a warmer season, and according to the degree of that altitude, and the cold consequent upon it, the season of its melting is later or earlier. While the snows of the low hills are rapidly melting by the warmth and the rains of March, it is at the same time snowing on the high mountains, whose previous stores are as yet unaffected by the weather. The increasing heat at length dissolves them in the order of their altitude, the highest of all melting at midsummer. It is therefore evident that as far as depends on the melting of the snow, streams rising in low hills must be highest in the spring, and streams rising in high hills in the summer; and the periods of the streams would thus be an index of the altitude of their sources. But when a river is fed by the snows of both high and low hills, we
cannot thus decide without adverting to other circumstances. If the low hills be extensive, the flood they occasion may surpass that arising from the melting of the high snows, under which are situated the uppermost sources of the river. If the river be highest in summer, we may decide that it has lofty mountains at its head. This conclusion
however is just only when we put out of view the periods of the rains, and decide from those of the thaws only. Both considerations must be combined in our judgment in particular instances, to which we now proceed.
80. The periods of the Indus and the rivers of the Punjab are nearly the same as those of the Ganges and its tributary branches, which are lowest in the winter, rise somewhat in the spring, and are highest in the middle of August. The rise in the great Ganges is perhaps gradual, certain, and nearly of the same quantity in different years; for being fed by many streams one chance and anomoly corrects another, but the same is not true of its branches, including the upper Ganges itself. The annual rise at Hurd war is six or seven feet; in the lower part of Bengal above the influence of the tide, it is thirty-one. This difference, may I believe, be shewn to be a consequence from the general principles of hydrostatics; it must therefore be supposed to exist in the case of the Indus and its branches, for they also run in a champaign country and yielding soil. My inquiries tend to confirm this opinion. After rains of uncommon severity the rivers of the Punjab sometimes rise to a great height; the effect however is temporary, and many seasons pass in which no such extraordinary floods occur. The great Indus after the junction of the Punjnud is from various causes less affected by local and temporary circumstances, but its regular and annual rise is greater than that of any of its branches. The branches have diversities among themselves not reducible under one general rule, but caused by special circumstances. The Ranee, which is the least of all the rivers, had yet in 1809 a rise equal to any of them. When other circumstances are the same, streams which run in sand increase more in breadth in their flood season, and those which run in clay increase more in depth. The annual rise of the great Indus I reckon about sixteen feet; that of the Ganges is thirtyone; and of the Nile twenty-four. The proportion in which their waters are respectively increased it would be more difficult to estimate. The same causes combine in the raising the Indus and its branches, and the rivers of our provinces-that it both thaws and rains. The effects in this respect are different, in that there is no inundation in the Punjab or Sindh, for we cannot apply that term where the tracts covered
are insignificant in proportion to the whole surface. The character of the Punjab is different from that of Bengal or Egypt. Instead of the banks of the river being higher than the remoter country, the various Doabs usually slope from their interior towards the rivers which bound them. Low tracts are sometimes found, which after heavy rains are covered to some depth with water; but there is no general inundation derived either from rain or from rivers, as in Bengal. The surface of the Punjab, however, after excluding the country beyond the Hydaspes, is lower above the level of its rivers than that of our Upper Provinces in general, with respect to the rivers which run
81. The periods of the Cabul river where it joins the Indus are nearly the same as those of it. It is lowest in the winter, notwithstanding the rains of that season in the valley of Peshawur. It is sensibly affected by the spring rains in February and March. It falls after they have passed over, yet not to its level in the winter, for now the snow of the lesser hills begins to thaw. At the end of May the middle snows begin to descend, and after them the upper, which bring the river to its greatest height at the beginning of August. We are to attribute the effect in part to the rains, which fall at that period at some of its sources (see paragraph 69.) Such is the history of the grand streams, but there is a diversity of circumstances with respect to the branches composing it. The Pech river swells early in spring, and declines from about the 28th of May. The Punjkora river follows nearly the same laws, though indeed heavy rain in the months of July or August will cause it to reach its greatest height in those months. The three streams in the valley of Cabul (see paragraph 36), the Lughman river, the Kashkar, and the Swad, with the rivulets of Jellalabad are highest in the month of July or August. The Bara is on the whole the greatest in the spring, but it rises and falls very suddenly, and very often according to the occurrence or cessation of rain in Teera. The To is probably greatest in spring; the Koorm is greatest in July or August, when it is swelled both by the Vuse (see paragraph 70) and by the thawing of the upper snows. The Gomul is perhaps the highest at the same time.
82. The diminutive streams of Bulochistan and Seeweestan are in general highest in the spring. The same is true of those found in the western Khoorasan, the Turmuk, and the little streams of the Kakna, Tureen, and Burch countries. Even those rivers which taking their rise in the Paraparnisan flow into Khoorasan, reach their greatest height during the periodical spring rains. The Helbund only which
rises in the most elevated part of that ridge continues to increase after that period. It perhaps reaches its acme the first week of June, but I have received contradictory information on the subject. The Murghab, and whatever streams are found in the Jumsheedee country, in Mymuna, and Undkho, may be presumed to be highest in the spring.
83. The Oxus and Jaxartes, and all their remaining branches which have been enumerated in the introduction, including the streams of Bulkh, rise in the spring, but are highest in the summer, notwithstanding the draught of that season. Some of the subordinate streams are higher in spring than in summer, but they are considerable enough to impart the same character to the principal ones into which they discharge themselves. With respect to the Neelum, and the rivers of Chinese Toorkistan, we know little beyond their names. From circumstances it may be conjectured that they are higher in summer than in spring.
SECTION IV.--Of Salubrity.
84. I am able to offer but a few detached observations on this subject. Its importance induces me not to pass it altogether in silence, although my opportunities have been small, and its natural difficulties are very great. There are few subjects on which opinions are so contradictory, and so many regular prejudices prevail. Medicine is at a low ebb in the country, and its professors entertain many absurd opinions respecting the original causes of disease, most of which they deduce from the qualities they attribute to different species of food, paying little regard to the operation of other causes, which among us are considered as the most palpable and powerful. The doctrines of Avicena are much followed, especially in Toorkistan. Physicians in these countries are not liberally rewarded, and many are obliged to travel from place to place in pursuit of a livelihood. These are chiefly natives of Peshawur and its neighbourhood, and their travels are principally confined to Toorkistan, which they visit on the opening of the spring. Few or no natives of Toorkistan or Khoorasan pass into other countries with such views. Some of these itinerants add the practice of the ruml, and other occult arts, to their accomplishments. They traverse great spaces, and being everywhere welcome, have the best