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distance, appeared to be moving. It was an awful visitation, and made every heart quake. In the direction of Peshawur, (eight miles distant,) clouds of dust appeared, which proved to have been caused by the falling of very many houses and buildings. A salute was fired from the battery at Jumrood, for the purpose of announcing the safety of Rajah Pertaub Sing, son of Maharajah Shere Sing, who is now at Peshawur, and of whom it is said, he narrowly escaped death; the building in which he had been sitting, came down almost immediately after he quitted it. The natives say, that a tenth of the city is down, and a number of the inhabitants killed."

Extract from a Letter, dated Kawulsur, 19th February, 1842.

"It is now about 12 o'clock mid-day, and we have just experienced a most awful Earthquake in camp. The natives say, that nothing so severe of the kind has been experienced in India for the last fifty years. The earth literally trembled like an aspen leaf, and rocked to and fro as an infant's cradle, or a ship at sea. Many of the camels that were earning the baggage of the troops moving up to Colonel Wild's camp were thrown down, and so great was the shock, which lasted fully five muutei, that I was obliged to support myself by holding on to the camp furniture, and many of the officers fancied themselves suddenly taken ill. I expected every moment to have seen the earth open and swallow us up, and it is only by God's great and merciful providence, that we have escaped through such an awful convulsion of nature.

*' Every one complains of nausea. We have just been observing immense volumes of dust, that completely darken the atmosphere in the direction of the old ricketty town of Peshawur, which is supposed to be nearly levelled with the ground, as the houses are but weakly built, being merely propped up by the beams of wood which may be observed placed in different spots under large walls and comers of the houses, and are even dangerous to passers-by at all times. I doubt not but that to-morrow's dawn will bring us dreadful intelligence, and produce a fearful account of lives lost.

20/A February.—" Reports say, that only from 40 to 50 of the inhabitants of Peshawur were crushed and killed among the ruins of the falling houses. General Avitabile's large dwelling house, which had recently been built, and was being finished, fell in, but luckily it did no injury to any one living in the house."

It will be observed, that the writers of these interesting letters differ at least an hour and a half, or two hours in their estimates of the time at which the shock was felt at Kawulsur, the first placing it between 10 and 11 A. M., the other at noon. By comparing the periods of the occurrence at stations farther removed from the focus of disturbance, as at Delhi, Poojnah on the Doab Canal, Saharunpore, and other places, to which more specific reference will immediately be made, I am disposed to consider the first of these estimates as the most correct, and to fix the period of the shock at Kawulsur at very little after 10 A. M.

Travelling in an easterly direction, the next notices we have of the Earthquake is its being felt at Delhi, where its period appears from all accounts to have been about 10 minutes past 11 A. M. On reaching Delhi, both the intensity of the shock, and the rate of propagation of the undulations seem to have materially diminished; and beyond the motion of the ground, no other effects are alluded to.

Still continuing easterly, and in a direction very little removed from a right line between the two places, the shock travelled from Delhi to Poojnah, a station on the Doab Canal, where its effects were observed bj Serjeant and Assistant Overseer J. R. Renny, and the following details connected with them were forwarded by him to me.

Extract of a Letter from Serjeant Renny, dated Poojnah, 19th
February, 1842.

"I also beg leave to inform you, that we felt a very severe shock of so Earthquake here at about half-past 11 A. M., it lasted about three mutes with intervals. My whole family felt it, as well as the people shout my place, who came running to me much alarmed. It was Srst noticed, I believe by myself, as I was then sitting writing, and found a heavy table on which my desk was laid, much agitated, which I thought was caused by some one moving, but I soon found my chair in motion also, and on looking about, I perceived every thing moveable in the room in a state of agitation. A few hours before this, I observed the water in the Canal was unusually muddy, and after the shock was over I went to look, and found the water much disturbed by a high swell, whether occasioned by the shock or not, I cannot say."

These details are unusually complete and interesting, and are very creditable to Serjeant Renny's powers of observation. The unusual muddiness of the Canal cannot possibly be due to the influence of the Earthquake, since the direction in which the shock travelled was against not coincident with that of the current in the Canal, hence the disturbance of the silt in the bed could not precede the shock; but it is quite possible, that the high swell observed after the shock had passed, may have been occasioned by it. The muddiness was probably caused by a fall of rain in the upper part of the Canal.

From Poojnah the shock travelled to Saharunpore, where it was just felt, but attracted no particular attention. It was next experienced at Kulsea, another station on the Doab Canal, fourteen miles to the northward of Saharunpore, where its effects were very perceptible. The motion here, as described to me by Mr. Sub-Conductor Pigott, was of the same undulating character as at Kawulsur, but its duration was certainly not more than a minute. Immediately on observing the shock, Mr. Pigott ran to the sun-dial, and found it precisely noon, or 12 o'clock. My camp was pitched about two miles north of Kulsea, on the south bank of the Nowgong Row, (or Stream,) but so feeble was the intensity of the shock, that although I was conscious of some peculiar motion at the time, it never occurred to me that it arose from an Earthquake, and it had passed from my mind, till recalled by Mr. Pigott's account of what had been felt at the same time at Kulsea.

By combining the preceding details, some interesting points may be determined; and first, as to the rate of progression of the undulation;. The maps I have had it in my power to consult, were not all so good as I could have wished, and the distances mentioned may possibly be a little incorrect, but not so, I believe, to any great extent. From Jellalabad to Peshawur, measuring in a straight line across the spurs of the Sullied Koh, the distance is 70 miles. From Peshawur to Ferozcpore, measuring similarly in a straight line, the distance is 280 miles, and from Ferozopore to Delhi 250, in all 600 miles. The period of the shock at Jellalabad is not mentioned, but at Peshawur it may be taken at 10 A. M., while at Delhi it was 10 minutes past 11 A. hence then 530 miles were traversed in 1 hour and 10 minutes, or tie shock travelled at a rate of 7.571 miles per minute, or 454.26 miles per hour. This, it is to be observed, is an average rate, and the velocity at Jellalabad and Peshawur was doubtless much greater, but a much more multiplied series of intermediate observations than we now have, would be necessary to enable us to form even an approximative idea of the law of decrement of rate of progress with reference to distance travelled. From Delhi to Poojnah is about 50 miles, and the times consumed in travelling from the one place to the other was 20 minutes, consequently the velocity of the shock was 150 miles per hour. Again, the distance from Poojnah to Kulsea is very nearly 36 miles, and the time 30 minutes, so that the velocity had diminished to 72 miles per hour, supposing the times to have been correctly observed, which, within a small limit, was probably the case. Hence then we have. Miles. Rate of progress of shock from Peshawur to Delhi, 454.26 per hour.

„ from Delhi to Poojnah, 150 ditto. „ „ from Poojnah to Kulsea, 72 ditto.

We may next attempt to form some estimate of the breadth of the undulations, of which there appear to have been several, although no data are furnished, from which we can learn either their number or individual extent. We must therefore content ourselves with estimating the total breadth of the zone of disturbance, as it may be called, at different points.

The duration of the shock at Kawulsur is said to have been 5 minutes, and supposing the velocity to have been there twice the average between Peshawur and Delhi, or 15.142 miles per minute, the breadth of the disturbed zone would be 75.71 miles, or in five minutes, a series of terrestrial waves, whose united breadth was this number of miles swept past Kawulsur. This is a horizontal measurement; but of the vertical height of the waves, on which their destructive influence chiefly depends, we can form no estimate, yet it must have been considerable, if we may judge from the ruin caused.

At Poojnah, the duration of the shock was considered to be three minutes, the velocity 2.5 miles per minute, and therefore the breadth of the disturbed zone was here 7 miles. While again at Kulsea, where the duration was one minute and the velocity 1.44 miles per minute, the breadth was 1.44 miles.

Whence we have, Miles.

Breadth of zone of disturbance at Kawulsur, 75.71

at Poojnah 7.00 » „ „ at Kulsea, 1.44

Whatever may be the effective cause of Earthquakes, whether undulatory motion communicated to internal masses of fluid matter, and from thence communicated to the super-imposed crust of the earth, or vibrations propagated from foci of disturbance through the solid crust itself, or a combination, as some facts would intimate of both these causes, there are two modes in which we may conceive these motions to be spread abroad. First, they may proceed in gradually enlarging circles, (as when a stone is thrown into water,) the focus of disturbance being the common centre; or they may be propagated along a distinct and defined track, (as when a string or wire is seized at one extremity and motion communicated to the whole from this,) when the focus of disturbance would be at one end. In the first case we would expect the effects of the Earthquake to be felt at points equi-distant from the centre at times approximating, but not exactly coincident both with each other, as the rate of progress of the undulations would necessarily be affected by the nature of the rocky crust through which they were propagated. In the second case, we would expect, that while the effects of the shock were more or less severe within certain limits, beyond these limits none would be experienced. All the information I hare been able to collect tends to shew, that the Earthquake of the 19th February 1842, belonged to this latter class, and if lines be drawn through Peshawur, Ferozepore, &c. with parallels through Jellalabad, which as yet forms the southern limit of the track, it will be found that the breadth of the district affected by the shock was somewhere about 40 miles, and in it are included the mountain ranges to the south, east, and west of Peshawur, with a considerable portion of what has been called the Salt range. This estimate has been formed solely from the facts collected by myself, and it may yet require to be much modified as our information extends. The method of what may be called the linear, in contradistinction to the circular propagations of Earthquake shocks, appears to me to lead very distinctly to the conclusion, that in

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