GEOLOGY.

Except in the south where are some ridges of sandstone and quartzite, Kolhapur comes within the area of the great Deccan trap fields. The chief varieties of trap are basalt, amygdaloid trap, 'vesicular trap, and clayey trap, which, with some few intertrappean sedimentary beds and numerous highly ferruginous clayey beds, make up the great mass of the trap-flows. The lower flows are mostly basaltic in character, the medium flows are alternately basaltic and amygdaloid, and the upper are chiefly basaltic capped by beds of clay and laterite. In the Sahyadris region the position of the flows is more distinct than further east. When carefully studied from some commanding point they are seen to dip at a very low angle generally to the north-cast. [The dip is too slight to be measured with a clinometer, but a calculation of the difference in the height of some of the chief trigonometrical stations which are capped by outliers of one and the same bed shows the north-easterly slope to range from nine to twenty-three feet a mile, giving a mean of sixteen feet a mile. Mem. Geol. Surv. XII. 173.] About twenty-five or thirty miles from the edge of the Sahyadris the dip becomes more easterly and so gradual as to be hardly traceable by the eye. The flows exposed in the Konkan show a very low westerly dip. The direction of the course of the upper waters of the rivers rising in the Sahyadri region and falling into the Krishna coincides with, the general dip of the trap-flows. It is probable, therefore, 'that the subaerial cutting of these valleys began immediately after the final outpouring of the last trap-flow, and has been ever since going steadily on. Till the whole of the Deccan trap area has been geologically examined, it will not be possible to say which was the last flow, but if the youngest of those now remaining in the Kolhapur and Belgaum Sahyadris was the last poured out, and represents the close of this tremendous volcanic activity, then the work done by atmospheric agencies since the close may be roughly estimated as a direct vertical erosion of 1000 to 1500 feet the latter depth being that of the valley of the Vedganga in South Kolhapur opposite the great mass of Bhudargad, one of the eminences capped by the highest of the remaining trap-flows. At present the most prevalent direction of the wind during the south-west monsoon, as shown by the inclination of the trees on the highest and most exposed ridges, does not coincide exactly with the dip of the trap-flows and strike of the main valley, but is more westerly by one or two points of the compass. The greatest thickness of the trap within the South Kolhapur area may roughly be estimated at 2000 to 2500 feet; it increases to the north. Further south the trap grows thinner for the beds forming the southern boundary of the area near the crest of the Sahyadris are high in the series and overlap by a wide space many of the underlying flows seen further north in the scarp overhanging the Konkan.

The grandest sections of the trap series are in the great western scarp of the Sahyadris; but their vast size often makes these hard to study, as some of the great basaltic flows form long unbroken lines of cliff several hundred feet high. They may be best examined along the two roads, one across the Phonda and the other across the Amboli pass. The cuttings along these roads give almost perfectly continuous sections of the whole thickness of the trap-flows they cross. The iron-clay bed, an outlier of the laterite is important as being the youngest known, the most constant, and the most safely determinable member of the Deccan trap series in this quarter. This iron-clay bed caps all the highest ridges and peaks in the Kolhapur hills and may be called the summit bed. Of all the mountains those which iron-clay caps are the most perfectly table-topped and in most cases the capping is sharply scarped all round the edge. As these scarped plateaus crown all the highest hills and were easily made very strong, many of them, notably Bhudargad and Samangad, were chosen by local chiefs as strongholds. The flows underlying this iron-clay bed show great likeness throughout the larger area they cover. The correspondence of flows in different great spurs is especially clear in the three ridges into which the Bhudargad spur divides. It is admirably seen looking west from the high bluff on the eastern ridge which towers over Belvadi. The view northward from Bolavi at the northern end of the lofty part of the western ridge on which Bhudargad itself stands, shows this correspondence and extensions of the flow-terraces most distinctly in all the ridges on either side of the Vedganga valley and in others beyond as far north as the Panhala mountain. [ Mem, Geol. Surv. XII. 182.]

Quartzites and sand stones are found at Vatangi covered on three sides by the flows of the Deccan trap series. If the ridge of trap which covers the quartzites west and north of Vatangi be crossed the quartzites will be found to reappear in the valley of the Hiranyakeshi river, and to occupy a very considerable area in that valley forming an inlier which may be called the Mangaon inlier, from the most important village which stands upon it. No peculiar features are presented by the rocks forming this inlier. They consist of quartzites and grits, mostly dipping northward, or north-by-west, at low angles. They are best shown in the row of hills which runs east-south-east from Sulgaon on the bank of the Hiranyakeshi river. The quartzites and grits are mostly pale coloured and fine grained, and form a series of beds several hundred feet thick, although both the top and the bottom of the series are hidden under trap. Petrologically identical with the Mangaon beds are beds forming several smaller inliers in the valley of the Vedganga, eight miles to the north-west. These latter lie in the centre of the valley between Ainghol and Shengaon, and are four in number, of which the south most, close to the village of Ainghol, forms a small but conspicuous isolated hill 200 to 300 feet above the plain. Here all the beds dip 5° to 10° north-north-west. The other inliers are simply exposures on the flanks of the great ridges. A great thickness of quartzites and grits of identical character is exposed in a small inlier at Phay in a side valley two miles west-north-west of Shengaon. In the valley of the Dudhganga two good-sized quartzite inliers lie north-west of the Phay and Shengaon inliers of which both on penological and stratigraphical grounds they must be considered the extensions, nor can it be reasonably doubted that they form a true link with the very similar series of rocks exposed at the foot of the Phonda pass nine miles to the west-north-west. As in the Mangaon and Shengaon inliers, the quartzites and grits of the Vaki and Aini inliers are pale coloured, whitish, drab, or pinkish, and fine grained. They have been little disturbed, rolling in angles of 8° to 10° in various directions. In both inliers the western edge passes under the trap with a westerly dip of 8° to 10°. The quartzites do not show in the valley of the Bhogavati between Valivde and the top of the Phonda pass. In the Aini inlier, the beds, which are nearly horizontal, cannot be less than 400 to 500 feet thick, measured from the level of the river. Both here and in the Vaki and to a less extent in the Phay inlier, the light coloured rocks have been so blackened by weathering, and perhaps by forest fires, that except on close inspection it is often difficult to recognize detached masses. [ Mem. Geol. Surv. XII. 92-94.]

CLIMATE.

The climate of the Kolhapur plain which varies from about 2000 feet above the sea in the west to about 1700 in the east, like the rest of the western Deccan is temperate. Towards the Sahyadri hills, which are covered with wood and drenched during the rainy months, the air is always cooler than in the east, which during April May and June is liable to hot easterly winds. At the same time almost the whole territory is under the influence of a sea breeze, which sets in during the afternoon and lasts till about eight at night.

The seasons may be broadly divided into wet, cold, and hot. The wet season, with an average fall of about forty inches, lasts from June to October. Except in the extreme west it is chiefly showery, seldom with such heavy continuous rain as to put a stop to field work. The rainy months are the healthiest time in the year. The strong damp breeze is always cool and pleasant and occasionally is cold. The daily changes of heat and cold vary from 67° to 88°. The cold season, which lasts from November to the end of February, is the most dry and unhealthy part of the year. Dry east winds, with no bracing or tonic influence, prevail and daily changes of heat and cold are considerable averaging about 83°. The hot weather lasts from March to June. The temperature is high during these months. In the daytime the air is hot at times rising to 97.8⁰ and averages about 91. 3°. The evenings arc cooled by a sea breeze and the nights are never oppressive. Its situation opposite a gap in the line of western hills gives Kolhapur city the benefit of a strong sea breeze and cool nights.

Meteors, igneous and luminous, arc of frequent occurrence. Violent storms of thunder lightning and wind are unusually prevalent, not only at the beginning of the south-west monsoon but occasionally at other periods. These storms appear to travel round the horizon often beginning and disappearing at the same point and not unfre-quently making the circuit twice. Though at times disastrous, the storms are generally beneficial to health. During April and May when the hot winds prevail, numerous hill forts, rising about 3000 feet above the sea, give a pleasant retreat. Of these hill forts Panhala, twelve miles north-west of Kolhapur, with good water and cool bracing air has been set apart as a health resort.

RAINFALL.

For the twenty-one years ending 1881 rain returns are available for six stations. During these twenty-one years the highest recorded fall is 361 inches at Bavda in 1861 and the lowest is five inches at Alta in 1865. As a rule rainfall varies with the distance from the Sahyadri crest. During the twenty-one years ending 1881, of the six stations at Alta, which is about forty-five miles east of the Sahyadri crest and twelve miles north-east of Kolhapur, the fall varied from forty-four inches in 1874 to five inches in 1865 and averaged twenty-three inches; at Bavda,. which is on the Sahyadri crest and thirty miles south-west of Kolhapur, the fall varied from 361 inches in 1861 to 121 inches in 1864 and averaged 220 inches; at Bhudargad, which is ten miles east of the Sahyadri crest and thirty miles south of Kolhapur, the fall varied from 120 inches in 1861 to thirty-nine inches in 1880 and averaged seventy-six inches; at Kolhapur, which is twenty-five miles east of the Sahyadri crest, the fall varied from fifty-six inches in 1874 to twenty-seven inches in 1870 and averaged 39.88 inches; at Panhala, which is twenty miles east of the Sahyadri crest and twelve miles north-west of Kolhapur, the fall varied from eighty-four inches in 1878 to thirty-seven inches in 1877 and averaged fifty-three inches; and at Vishalgad, which is on the Sahyadri crest and about thirty-five miles north-west of Kolhapur, the fall varied from 111 inches in 1875 to thirty-two inches in 1877 and averaged sixty inches. The details are:

Kolhapur Rainfall, 1861-1881,

Kolhapur Rainfall, 1861-188I—continued. [Besides these, rain returns for the station of Kolhapur are available for the ten years ending 1860. During these ten years the fall varied from sixty-four inches in 1853 to thirty-four inches in 1860 and averaged forty-five inches. The details are: In 1851 thirty-seven inches, in 1852 fifty-six inches, in 1853 thirty-four inches, in 1854 forty-four inches, in 1855 thirty-nine inches, in 1856' fifty-two inches, in 1857 forty-six inches, in 1858 forty-two inches, in 1859 thirty-eight inches, and in 1860 thirty-four inches. ]

HEAT.

Kolhapur heat is temperate. During the thirty-one years ending  1881 the yearly maximum varied from 97° in 1872 to 79° in 1851 and averaged 87°; the yearly minimum varied from 74° in 1851 to 62° in 1872 and averaged 67°; the yearly mean maximum varied from 87° in 1876 to 79° for the five years ending 1858 and averaged 83°; and the yearly mean minimum varied from 74° in 1860 to 67° in 1872 and averaged 70°. A return of the thermometer readings for the thirty-one years ending 1881 is given in the Appendix.