In addition to these an account of a submarine eruption off Ramri Island, which was actually witnessed from the deck of a passing steamer, has been given by Dr. Pascoe.1

From 2nd March, 1912, the date on which the mud volcano situated on the submerged reef to the south of Cheduba, known as the Hlaing-bank-kon or as the "Drunken Sailor Rocks," burst into activity, until 1st May, 1914, when an islet appeared above the level of the sea to the south of West Baronga Island, and from that time until the 14th November, 1923, conditions appear to have been quiescent, or, if any eruptions have taken place, they have failed to attract attention, which is unlikely. It now remains to bring these accounts up to date by relating the narratives of observers. They are prefaced by the one which has already been given in part by Dr. Pascoe, but which has not yet appeared in the Records, while the Memoir in which it is reproduced is now out of print.

Submarine Eruption of 30th September, 1908.

On the 8th October, 1909, the Marine Department of the Government of India in Simla issued the Miscellaneous Notification No. 1318-M., being a copy of a telegram from the Secretary to the Government of Burma, to the Secretary to the Government of India, Marine Department, No. 201-C., dated Maymyo, the 6th October, 1909. The notification is given below:

"Following telegram received from Port Officer, Akyab. Begins. Commander, S. S. Katoria, reports witnessed a great volcanic upheaval approximate latitude nineteen dash twenty-one and one-fourth longitude ninety-three dash twenty-two. first upheaval five thirty-five P.M., second five fifty P.M. thirtieth stop each lasting two to three minutes. Ends."

On the 23rd November, 1909, Commander A. R. W. Handcock of the British India Steam Navigation Co.'s R. M. S. Katoria kindly forwarded the following account of these occurrences to the Director, Geological Survey of India :--

"On the afternoon of the 30th September, 1909, whilst on a voyage from Rangoon to Kyaukpyu, I observed a remarkable volcanic upheaval in latitude 19° 21' north and longitude 93° 22′, an account of which may, I think, prove interesting to your Survey Department. The circumstances are as follows:-On the afternoon in question I was steaming up the coast at about 113 knots an hour on a N. by E. course, weather fine with passing clouds, and a light S. W. wind, when at

1 E. H. Pascoe : The Oil Fields of Burma "; Mem., Geol. Surv. Ind., XL,

p. 197,

5-30 P.M. suddenly there was a disturbance right ahead and about 5 miles distant. The disturbance at first resembled the thick black smoke of a steamer on a far off horizon; this was quickly followed by clouds of steam somewhat resembling a near view of a waterspout in the making; and about 20 seconds later a great upheaval of water and huge black masses of mud which were so clearly defined at their edges that they resembled great rocks being thrown up in the air, and at first I believed it to be an entire rocky island being thrown up out of the bed of the ocean. This lasted about two minutes, when it rapidly subsided, leaving the water muddy and discoloured round the scene of the upheaval. The height to which the upheaval reached was about 200 feet above the sea, and the length from east to west about 1,500 feet. These measurements are very nearly correct, as there was a steamer nearer the upheaval than I was myself, and as I was able to precisely place the position of the volcanoes, I was therefore in a position to judge dimensions by comparison. At 5-50 P.M. a second upheaval took place also lasting about two minutes, which was similar to the first one and in the same place, though the length from east to west of this, the second eruption, was about 1,000 feet only. The depth of water at the spot is about 13 fathoms. After the upheavals the wind in the vicinity dropped to a calm, though after steaming some 8 miles out to sea, the light S. W. wind set in again.

The clearly defined edges of the black mud as distinct from and not mixed with the surrounding water can, I believe, be accounted for by the fact that petroleum exists in more or less quantities about this part of the Burma coast, and the mud was probably saturated with oil.

The force represented to force up such a large body of mud and water from some 80 feet below the surface of the sea to 200 feet above the surface of the sea must have been very great."

Submarine outbursts of this character and extent have seldom been actually witnessed at the moment before. A search through the old records from 1843 onwards reveals the fact that although flames and their reflections from banks of clouds have been seen, both from the mainland and from the sea, although mud islets of varying sizes, with and without active craters, have been observed, this is the first occasion in which the actual process of a violent eruption at sea has been watched from start to finish. There are several accounts of eye-witnesses of eruptions of the mud volcanoes on land of course.

In one particular, Commander Handcock's narrative recalls that of an earlier observer. In the early hours of 15th December, 1906, a very severe submarine eruption of a mud volcano took place in latitude 19° 0′ 6′′ N., and longitude 93° 24′ 20′′ E., 83 miles in a northwest by north direction from the north-westernmost point of Cheduba Island. Four and a half miles south-east by south from the site lies Beacon Island, and it so happened that Mr. S. Dawson, the Inspector of Light Houses to the Government of Burma, was on this

66

island at the time. He observed the new land at about 7 A.M. in the morning and "about 9 A.M. noted black smoke in two jets like that of a steamer in the distance, and these gradually turned to white steam issuing in one enormous 'cumulus' the whole length of, and above, the island. Later, huge volumes of black mud and water spouting up into the air to a height of what must have been. hundreds of feet " were seen.1 Commander Handcock's report mentions thick black smoke recalling a steamer on a distant horizon, followed by clouds of steam and then by the eruption of water and black mud. The only material differences in the two occurrences are that the preliminary eruptions, which gave birth to the island on 15th December, 1906, were not witnessed, whereas those of the one under discussion were not large enough to raise an islet above sea-level at all.

Submarine Eruption about 1st May, 1914, off West Baronga Island.

On May 4th, 1914, a notification was issued by the Marine Department in Rangoon, stating that an active mud volcano had appeared in latitude 19° 40′ N. and longitude 93° 02′ 15′′ E. Its height on May 1st was about 30 feet and its length about 1 cable, and it showed two summits. Its position was off the long island of West Baronga, near Tiger Point and apparently on the track of vessels between Kyaukpyu and Akyab.

Copies of the notification appeared in the Indian newspapers of May 5th, followed by more detailed accounts on the 6th and 8th of May.

From these it appeared that the island was first sighted from the S. S. "Katoria," a vessel belonging to the British India Steam Navigation Company, Ltd., on May 1st. No active eruption was noticed, but merely an island in a locality where there should have been clear water. In an interview with an Englishman representative, which appeared in that newspaper on May 6th, the Commander of the S. S. "Katoria" is reported to have made the following

statement:

"From all appearances it is an island, about a mile in extent and from 25 to 30 feet high. What confirms my conviction that it is an island is its proximity to the island of Baronga, and I should not be at all surprised if it is found to be a part of

'J. Coggin Brown: "Recent Accounts of the Mud Volcanoes of the Arakan Coast Burma." Rec., Geol. Surv. Ind., XXXVII, pp. 269-272, (1908).

this island. Another thing that strengthens my belief is the earthquake report issued from Simla last week, for that report stated that the shock came from about a thousand miles distance, and Baronga Island is just about that distance from Simla. Since no other report that would account for the shock has been made it is more than probable that this eruption was the quake recorded on the Simla seismograph."

Later accounts stated that the new mud island, situated about 8 miles south of Baronga Point, was the first to appear in the region for several years, although a number of years previously they were of common occurrence. The R. I. M. S. Mayo passed quite close to the island on the same day as the S. S. "Katoria," and a copy of the report from the Officer commanding the former vessel to the Port Officer, Akyab, is given below:

"I have the honour to report that a mud volcanic island has appeared to the south of Baronga Point in latitude 19° 40′ N. longitude 93° 2′ 15′′ E. Height about 30 feet, length about one cable, in two mounds.

A line of soundings was obtained off the island of 14 fathoms, L. W. O. S., from a position with the island bearing N. 60° E., true distance 23 miles, to a position with island bearing N. 60° E., true distance 1 mile. Ship's course being N. 30° W. true. The water to the S.-E. of this volcanic island was discoloured for some distance, at least a mile or more. A heavy surf was breaking on the island at the time I was passing, and it was also blowing from the N.-W. (force about 7). I therefore did not lower a boat to make a close inspection.

Suggest that all shipping may be informed at the principal ports."

The island was slowly worn away by the action of the waves and tides and finally disappeared, leaving a dangerous shoal.

Submarine Eruption about November 14th, 1923, off West Baronga Island.

The Indian newspapers of November 16th, 1923, published the following information :—

"The Commander of the steamer Chakinda' reports that an island has been formed approximately 1,000 feet long and 20 to 30 feet high, in a position 8.4 miles south and 3. degrees east true from Baronga Point on the spot marked Volcano 1914."

Mud

"Chakinda" elicited

A reference to the Commander of the S. S. the reply that he had no further information to add to this telegram.

At a later date the following report on the occurrence was received from Commander A. G. Maundrell, R.I.M., Port Officer,

Akyab. It is a copy of one submitted to the Principal Port Officer oi Jurma.

"The island was examined on November 25th, 1923, and its position fixed as being 8.4 miles, 176 from Baronga Point. The island is composed of black mud, which, being in lumps, gives the idea of rocks, particularly so at the north and south points, where the washing away process has left a few pinnacles. The island is flat-topped, with perpendicular sides and slight ridge running north and south. It is now almost circular, of about 600 feet diameter and 20 feet in height. When fixing its position, the island was circled round at a distance of to of a mile, and no sounding of less than 11 fathoms was obtained. The island was also circled round in a boat at a distance of not more than 200 yards. The island is washing away chiefly from the western side, on which side, at 200 yards distance, soundings of 4 fathoms to 7 fathoms were obtained. On the south side the island is steep to 9 fathoms, close along side on the east side 7 fathoms at 150 yards, and on the north side 7 fathoms at 200 yards. Inside of these distances the water shoals rapidly, and breakers are to be expected. Much discoloured water was passed through when circling the island, and this would appear to be chiefly due to the washing away process, it being noticed that on the flood this discolouration was mostly to the north-east and on the ebb to the westward. It is, I consider, likely that before long the island will disappear, leaving a dangerous shoal, as occurred in 1914. Owing to the scend of the sea, it was impracticable to land."

The Port Officer adds that the island was first discovered by the Master of the S. S. "Chakinda" on November 14th, 1923, and that so far as he could ascertain, there were no eye-witnesses of the eruption. The Geological Survey of India is also indebted to Commander Maundrell for a tracing of Admiralty Chart No. 1369 showing the exact position of the island and details of the soundings around it. A comparison of this with the chart itself shows that the new island coincides exactly in position with the one which was formed on May 1st, 1914, and there is no doubt that they were both due to eruptions of mud from the same vent in the floor of the sea. The prediction that the island would disappear and leave a shoal was proved by the receipt of the following wireless message by the Principal Port Officer, Burma, on the 29th February, 1924, from the Master of the S. S. "Chantala."

"Island reported by Master, Chakdina, in position 8.4 miles S. S. E. true from Belonga Point has now disappeared and there is nothing showing above water. Breakers mark the position."

EXPLANATION OF PLATE 17.

Map showing position of mud volcano which erupted in May 1914 and November 1923. From Admiralty Chart No. 1369.