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the shaking more; some who were upstairs, thinking there had been a heavy explosion, rushed down and even out. The effects were felt at Shillingford, two miles distant, and also at Combehead, one and half mile distant, and considerably higher. A small piece of wall was thrown down in the town, but no further damage was done. The porters at the station felt the shock like a heavy mineral train passing. I am not prepared to say what was the duration of the shock; it was certainly felt by the majority of the inhabitants as a heavy passing body." A medical gentleman residing at Bampton was sitting in his room, heard a noise which he thought resulted from the fall of a large water-butt from its stage in the yard, and which he fancied was rolling over the stones. On going out immediately to examine he found that nothing, so far as he could see, had been disturbed.

At Petton Cross a young farmer exclaimed in the midst of the family-circle, 'Hark! there's a train coming. What can it mean at this time of the night?' All heard the noise, which ceased after six or seven seconds, and was not heard again." This was communicated by Rev. W. Harpley.

I addressed a letter to Rev. Canon Hillyard, of Oakford, four miles north of Bampton. In the absence of the canon this was very kindly answered by the Rev. G. Molyneux, who says, "I find on making enquiries that some ladies noticed an unusual rumble' as though a heavy waggon or traction-engine were passing, but they felt no motion. They described the sound as being like the roar produced by a chimney on fire, and went so far as to satisfy themselves that such was not the case."

This shock has been distinctly traced from where it was first felt for about twenty-four miles, from Taunton to Oakford, in the direction of east to west, and, so far as it can be traced, it seems to have been along the line of junction of the Devonian and Carboniferous systems. For the first ten miles from Taunton to the outcrop of the Carboniferous, the shock was through the New Red Sandstone Series; but the rest of the way to Oakford was apparently in the junction of the older rocks. There can, I think, be little doubt that both the Devonian and the Carboniferous are buried beneath the New Red Sandstone Series; the shock may therefore have begun and followed the line of junction, although at first deep down beneath the Trias.

With so much independent evidence as has been in this instance educed there can, I think, be little doubt as to the cause of the alarm created; and although no particular

damage was done here, it appears quite evident that the old forces are still active, and may at any moment exert themselves to a much greater extent than they have done within the historic period.

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In the active seismic region in Japan the action and the effects of recent earthquakes have been carefully studied by Mr. John Milne, professor of mining at the Imperial College of Engineering at Tokio, Japan. This gentleman says, "The earthquake may be compared with the effect produced by a charge of dynamite exploded beneath the surface of the ocean. In the vicinity of a point above, or nearly above the explosion, the disturbance is violent and destructive, while at a distance the motion is principally felt as waves which are being propagated horizontally." I have not been able to fix on the exact locality where the shock occurred, the wave of which was felt along the line from Taunton onwards for about twenty-four miles; but so far as the wave has been traced, it appears to have traversed the line of least resistance; namely, the junction of the Devonian and Carboniferous systems.

* Times, p. 12, May 26th, 1885.

ON THE

PROBABLE VOLCANIC ORIGIN OF THE BRECCIAS AT THE BASE OF THE TRIAS IN SOUTH DEVON;

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THE object of this paper was to show that the Breccias forming the basement beds of the Trias, as developed in South Devon, presented to the writer many appearances which strongly inclined him to the belief that their formation was only to be satisfactorily explained on the grounds of contemporaneous volcanic action, which commenced by blowing off the upper covering of surface rocks, shattering them into angular fragments, which were immmediately or shortly afterwards deposited along with other ejected materials of a finer nature before any great amount of abrasion had taken place.

In proof of this statement the writer referred to the tufflike nature of much of the materials cementing the Breccias together, their resemblance to similar tuffs which he had seen. both in the Old Red and Carboniferous systems of Scotland, which, like these associated with the Breccias, were entirely, or almost entirely, made up of the local rocks through which the volcanic vents had passed; they also bear a striking resemblance to the tuffs of the Eifel.

In further support of his theory he pointed to the contemporaneous traps at the base of the Triassic system in Devonshire, portions of which had occurred as true lava flows, and also to beds of ashes and volcanic sand. These and other facts proved that volcanic agency was active during the beginning of the Triassic period in Devonshire.

The beds from which this partial volcanic origin was inferred are strictly confined to the very base of the system, and not to the higher portions or conglomerates proper.

SEQUEL TO A CONTRIBUTION TO

THE COMPARATIVE METEOROLOGY OF TORQUAY, TEIGNMOUTH, AND SIDMOUTH.

BY W. C. LAKE, M.D.

(Read at Seaton, July, 1885.)

IN a note subjoined to a paper read for me last year at Newton, on the Comparative Meteorology of Torquay, Teignmouth, and Sidmouth, and published in the Transactions of the Association, I stated that since the paper had been read an error had been discovered in my dry and wet bulb thermometers, which completely vitiated the observations of humidity for the station at Bitton, Teignmouth.

The facts are these:

My dry and wet bulb thermometer was one of Negretti and Zambra's, Kew certified in 1869. At that time the readings of the dry and wet bulb at the freezing-point were respectively 32.0° and 31.9°, showing 0·1° as the difference for that degree between the two thermometers. In November, 1875, I tested them for the freezing-point again. They then read respectively 32.4° and 32·3°, showing a rise of 0·4°, but the same difference 0.1° between the two thermometers. This index-error I subsequently reckoned in my observations.

When Mr. Marriott came round in August, 1884, to examine the various stations, he tested the two thermometers with standard tubes, and found that while at 62° the dry bulb agreed with what it had been in 1875, the wet bulb differed from it now by 0.9°. Subsequent testings, which I applied at various temperatures, showed that this difference ranged from 11° at 90° to 0.5° at 50°. I then sent the instruments again to Kew; but unfortunately the dry bulb was broken in transitu; and though I asked that the wet bulb

(the one in fault) should be tested, yet the tube sent back to me, with a certificate of verification, was certainly not the one I sent up.

From the impossibility of ascertaining what the ratio of change had been in the wet bulb between 1875 and 1884, I have felt, in consequence, obliged to cancel all my observations on humidity made of late years.

In the paper read last year I gave the means for the three years 1880-1882 of the mean maximum temperature, mean mininium temperature, mean humidity, and mean amount of rain for each month of the year at each of the stations considered. As the deductions there made hold good in everything except the humidity at Bitton, I will not repeat them, with the exception of the degrees of humidity, but give in addition the mean temperatures (taken from the mean values of the maximum and minimum temperatures), and the mean daily ranges of temperature.

They will stand then as follows, the stations being with their heights above sea-level: Castle College, Torquay, 166 feet; Rocombe, Torquay, 400 feet; Kirkham, Babbacombe, 293 feet; Bitton, Teignmouth, 50 feet; Woodway, Teignmouth, 235 feet; and Sidmount, Sidmouth, 186 feet. (See Table.)

It will be seen thus that as the means of the three years during which the observations were taken

COMPARING CASTLE COLLEGE WITH ROCOMBE,

The mean temperature at these two stations was alike for March and October, was higher at Castle College for each month from November to February, also in April, June, and July, and was lower at Castle College for May, August, and September; the greatest difference having been 0:3° for November and December, and 0.5° for September, for the other months the differences having been less than 0.5°.

The mean daily range at these two stations was alike in December, was greater at Castle College for January, and less at Castle College for every other month; the difference being greatest for March (1·3°), April (2·3°), May (1·6°), and August (1.3°).

The mean humidity was alike at these two stations for July, August, and November; greater at Castle College for March, April, May, June, September, and December; and less at Castle College for January, February, and October, these differences being only equal to 1 per cent. generally,

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