Page:Encyclopædia Britannica, Ninth Edition, v. 12.djvu/763

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.
739
HOR — HOR
739

GEOGRAPHY.] INDIA 739 At the junction of the Eastern and Western GMts rises the bold triangular plateau of the Nilgiris, and to the south of them come the Anamalais, the Palms (Pulneys), and the hills of Travancore. These ranges are separated from the Nilgiris by a broad depression or pass known as the Palghat Gap, some 25 miles wide, the highest point of which is only 1500 feet above the sea. This gap affords a passage to the winds which elsewhere are barred by the hills of the Ghat chain. The countrj 7 to the east of the gap receives the rainfall of the south-west monsoon ; and during the north-east monsoon ships passing Bey pur meet with a stronger wind from the land than is felt elsewhere on the Malabar coast. According to Captain Newbold, this gap "affords an outlet to those furious storms from the eastward which sweep the Bay of Bengal, and, after traversing the peninsula, burst forth through it to the neighbouring sea." In the strip of low country that fringes the peninsula below the Ghats, the rainfall is heavy and the climate warm and damp, the vegetation being dense and characteristically tropical, and the steep slopes of the Ghats, where they have not been artificially cleared, thickly clothed with forest. - In Bunnah, the country around Ava, as well as the hill country to the north, has suffered from severe earthquakes, one of which destroyed Ava in 1839. The general meri- dianal direction of the ranges and valleys determines the direction of the prevailing surface winds, this being, how ever, subject to many local modifications. But it would appear, from Dr Anderson s observations of the movement of the upper clouds, that throughout the year there is, with but slight interruption, a steady upper current from the south-west, such as has been already noticed over the Himalayas. The rainfall in the lower part of the Irawadi valley, viz., the delta and the neighbouring part of the province of Pegu, is very heavy ; and the climate is very mild and equable at all seasons. But higher up the valley, and especially north of the Pegu frontier, the country is drier, and is characterized by a less luxuriant vegetation, and a retarded and more scanty rainfall. Observatories. Meteorological observatories have been established at one hundred and three stations in India (including British Burmah and the Andamans). These observatories are situated at all elevations, from the highest, Leh (11,538 feet above mean sea-level) and Chakrata (7051 feet), to Negapatam (15 feet) and Sagar Island, the lowest, which is only 6 feet above mean sea-level. - Temperature of the Air. From the average annual mean tempera tures of 83 stations (derived from the means of three or more years) the following figures are taken. In the following four stations in this list, the average mean yearly temperature was over 82 F. : -Trichinopoli, 82 8; Vizagapatam, 827; Madras, 82 4; and Madura, 82 2. All of these stations are in the Madras Presidency. The next highest means are returned by Negapatam (also in Madras), 81 9 J ; Cuttack and Port Blair, each 80 -5; False Point, )-20; Goa, 79 9"; Cochin, 79 8 ; Sagar Island, 79 5; Deesa, 9 4; and Calcutta, 79 2. The mean annual temperature of Bombay is 78 8, so that it is the coolest of the three presidency towns. The lowest means are obtained at the hill stations of Darjjling, 53 "9 ; Simla, 54 -4; Murree, 55 8 ; and Chakrata, 56 1. Between these and the next coolest stations is a great gap Ram khet following with 60-4, Pachmarhi with 687, and Rawal Pindi with a yearly mean of 69 "4. The highest mean monthly temperatures given are : 95 at Multan, in June ; 94 -3 at Delhi, in June ; 941 at Jhansi, in May ; 93 6 at Lucknow, in June. 1 he lowest monthly means are returned by the four coldest hill stations mentioned above, the figures being : Murree January 377, February 39 "4; Simla January 39 6, February 41 -1 Chakrata January 40 -8, February 42 -9; Darji ling -January 107 , February 43 -2. The mean temperature at Leh in January is li & , and in December 24 4. Atmospheric Pressure. The meteorological report for 1877 con tains a table showing the annual mean pressure at 72 stations cor rected (except in the case of Madras) to the Calcutta standard, which reads 0-011 inch higher than that of Kew. From that table the mowing figures are obtained. The mean yearly pressure at the highest stations is 23 "274 at Chakrata, 23 "371 at Darjiling 24 058 at Ranikhet, 26 416 at Pachmarhi, and 26 932 at Bangalore. The greatest annual mean pressures returned are 29 862 at Negapatam, 29-856 at Madras, 29 822 at Bombay, and 29 821 at False Point. Rainfall. The average annual rainfall at 294 stations is recorded Rainfall. in the 1877 meteorological report, from which the following figures have been obtained : In the Punjab the highest average fall (123 21 inches) is at Dhannsiila, which is situated on the face of the hills, and exposed to the full force of the monsoon ; the next highest recorded is little more than half that amount, or 68 61 inches at Simla. The lowest average falls in the Punjab are 6 16 inches at Muzall argarh, 6 93 at Multan, 7 35 at Deni Ghazi Khan, and 8 23 at Dera Ismail Khan. All these stations are protected by the Sulaiman range from the monsoon. p In Rajputana and Central India the maximum average is 20 27 at Jaipur (Jeypore), and the minimum, 60 85 at Mount Abu, the highest point in this part of India. In the North-Western Provinces the heaviest average falls are at Naini Till (94 -17 inches) and Dehra (70 06), both of which lie high ; the minimum average fall is 24 32 at Ah garh, the next lowest figures being 26 18 at Muttra (Mathura), 26 46 at Agra, and 2674 at Etah all stations on the plains. In Oudh the maximum rainfall is at Sultanpur, 4672 inches ; areli, 39 99 inches. and the minimum at Eai Bar Chittagong, 105 61, both on the north-east coast of the Bay of Bengal. The lowest averages are returned by Chapra, 37 06 inches ; Patna, 38 21 ; and Gaya, 41 38. The average rainfall for Bengal is 67 inches. Assam possesses in Cherra Poonjee (Chani Punji) the station with the largest recorded rainfall in the world. The registered fall during the three years ending 1876 averaged 368 41 inches. A total fall of 805 inches was reported in 1861, of which 366 were assigned to the single month of July. In 1850 Dr Hooker registered 30 inches in twenty-four hours, and returned the fall from June to November of that year at 530 inches. In the four days 9th to 12th September 1877, 56 19 inches were registered. The following stations in Assam have also a very high rainfall : Silchar, 121 07 ; Sylhet, 153-80 ; Dibrugarh, 116 43 ; and Tura, 11576. The lowest recorded averages in Assam are at Samaguting (52 58 inches) and Gauhati (69 23 inches), both on the northern side of the hills separ ating Cachar from Assam. In the Central Provinces the highest average falls are at Pach marhi (82 20 inches) and Baldghat (64 11 inches) ; lowest averages, Khandwa, 32 26 inches, and Bednur, 41 21 inches. In Bombay, three stations on the Ghats are recorded as having an average rainfall of over 250 inches, viz. : Matheran, 256 75 inches ; Malcolmpet (Mahableshwar), 252 25 ; and Baura (Fort), 251 80. The lowest average rainfalls recorded in Bombay are 12 -99 inches at Maiidargi ; 17 25 at Dhulia ; and 19 93 at Gokak. The average rainfall for Bombay is 67 in-ches. In Sind the average rainfall is very low, varying from 16 31 inches at Nagar, and 1178 at Urnarkot, to 5 09 at Shikarpur, and 4 -28 at Jacobabad. In Madras the highest averages recorded are 135 60 inches at Cannanore ; 131 91 at Mangalore ; 125 63 at Tellicherri ; 113 62at Calicut ; and 112 15 at Cochin all on the west coast. The lowest falls recorded are at Bellary, 16 06; Tuticorin (sheltered by the Ghats), 18-50 ; Guti (Gooty), 20 85 ; and Coimbatore, 20 90. All these stations lie low. The average fall at the stations on the east coast is about 41 inches. The average rainfall for Madras is 44 inches. The rainfall along the coast of British Burmah is heavy, as might be expected, the following averages being recorded : Sandoway, 218 -58 inches ; Tavoy, 195 47; Maulmain, 191 34 ; Akyab, 189 23 ; Khyouk-hpyu, 170 76. The smallest rainfall is at Thayet-myo (51 04) and Prome (59 46), sheltered by the Yoma range. The rainfall at Port Blair, in the Andamans, is also naturally heavy, the average being returned as 116 25 inches. Sun-spot Cycles. The conclusions arrived at by the Indian Sun-spot meteorological department on the subject of the sun-spot cycles cycles, which have been engaging the attention of scientific an<l men, are thus summed up in the 1877 report : "In con clusion, the following are the more important inferences that the meteorology of India in the years 1877 and 1878 appear to suggest, if not to establish. There is a tendency at the minimum sun-spot periods to prolonged excessive pressure over India, to an unusual development of the winter rains, and to the occurrence of abnormally heavy snowfall over the Himalayan region (to a greater extent probably in the western than the eastern Himalayas).

This appears also to be usually accompanied by a weak