as from small ones under the same circumstances, will not be considerable, unless the circuit be completed; that is, unless some matter, non-electric in a considerable degree, and in contact with the coatings of the phials, is brought into contact, or nearly so, with such non-electrics as communicate with the matter contained in the phials themselves. When indeed the circuit can be completed, the explosion from the large glasses is prodigious; the whole quantity of electricity accumulated, or nearly so, being discharged in an instant. But the fact is otherwise if the circuit is not completed, and the iron rod in the mouth of one of these phials is touched by a non-electric (the hand of a man for instance) not in contact with the tail wire: for then there will be no explosion, no shock; but the person approaching his finger near the iron rod, will see a succession of small sparks, more intensely red than that large one seen when the phials explode at once; and the person making the experiment will feel a very pungent pain, but confined to that finger which touches the iron rod. This succession of sparks continues till the electricity accumulated in the phials is nearly exhausted. So that the explosion from any given quantity of electricity, accumulated as before-mentioned, is greater or less in proportion to the time expended in making that explosion: in like manner as a given quantity of grained gunpowder rammed hard in a pistol, is almost instantaneously fired, and that with a great report; when the same quantity of gunpowder rubbed fine, and rammed hard, takes a considerable time in burning as a squib, and makes no explosion.

From what he has advanced, it may possibly be conjectured, that the electrical effluvia occupy only the surfaces of bodies electrised; as we found that a very small quantity of matter, distributed under a very large surface, would occasion a greater accumulation of electricity, than a much more considerable quantity of matter under a less. But that the electricity occupies the whole masses of bodies electrised, and passes through their constituent parts, Mr. W. thinks is clearly demonstrated by the following experiments..

He enveloped an iron rod, about 3 feet in length, with a mixture of wax and resin, leaving free from this mixture only one inch at each end. This iron was warmed, when thus fitted, that the whole of its surface where it was intended might be covered. This rod, when electrised at one of its ends, snapped as strongly at the other, as though it was without the wax and resin. This could not have happened from the electricities passing along the surface of the iron rod, because there it was prevented by the originally electrics, and consequently must of necessity pass through it.-Again, a phial of water in the experiment of Leyden can be electrised, and may be caused to explode, though the wire, touching the water in the phial in making that experiment, be run through a wax stopple, exactly fitted to the mouth of the phial.

He caused a glass tube, open at each end, and about 2 feet and a half long,

to be capped with brass cemented to the ends of the tube. In the centre of each of these caps was fastened a slender brass rod; and these were disposed so in the tube, as to come within half an inch of each other. When the tube was properly suspended in silk lines, with one of its extremities near a glass globe in motion, the brass work at both ends snapped equally strong. As the electricity could not pass along the surface of this tube warmed and wiped clean, this effect could not have happened, unless the electricity pervaded the substance of the brass caps. On touching the brass at the end of the tube most remote from the electrifying machine, the snaps from one of the brass rods within the tube to the other were scen to correspond with the snaps without. More experiments of this kind might be added, but these he presumes, are sufficient to show, that the electricity occupies the whole masses of non-electric bodies electrised.

Mr. W. mentions a series of experiments he had made in vacuo; from the comparison of which with the experiments in open air, it appears that our atmosphere, when dry, is the agent by which, with the assistance of other electrics per se, we are enabled to accumulate electricity in and upon non-electrics; that is, to communicate to them a greater quantity of electricity than they naturally have: hence also we see, that on the removal of the air, the electricity pervades the vacuum to a considerable distance, and manifests its effects on any non-electrics, which terminate that vacuum: and by these means that originallyelectric bodics, even in their most perfect state, put on the appearance of nonelectrics, by becoming the conductors of electricity.

On the Bones of a Fetus being Discharged through an Ulcer near the Navel. By Mr. Francis Drake, Surgeon, F.R.S. N° 485, p. 121.

The wife of James Burman, labourer, at Scawby near Brigg in Lincolnshire, was about 29 years of age when she married. About two years after, having had a child at full time, she conceived again, and went regularly on for 4 months. She then got a fall, and about 3 weeks after felt a load in her belly, which continued, on the right side of the same, between 2 and 3 years. The woman then grew very big with another child, which pressed so much on the lump as to give her great uncasiness. However, she went on to her time with her double burden; and 34 years after the accidental fall, she was delivered of a live child at full growth: from which time she became worse, with violent pain about the navel, and an inflained tumour appeared near that part. On application to a neighbouring surgeon, fomentations were used, which produced a suppuration at a small breach near the navel. The surgeon did not know what to make of this swelling, and therefore did not venture to enlarge the orifice; but it continued discharging a fetid purulent matter for three or four months longer. About a year, or more, after her last delivery, the woman was suddenly seized

in the night-time, and a hardish mass of flesh, seemingly about 8 inches long, was discharged through the old opening in her belly. The lump was rather thicker than an ordinary man's wrist, and which, being opened, contained all the bones of a fœtus, of about 4 months' growth.

At this time the woman was much emaciated, occasioned by the large discharge of pus from the wound; and what was much more extraordinary, whatever she ate or drank came half-digested through the opening. White bread, or better diet, came through in that manner; but coarse rye-bread, or such-like, was not digested at all. For which reason, the poor woman must have inevitably perished, had she not been supported by a charitable gentleman's family in the village, with diet fit for her miserable circumstances.

She continued to discharge her excrement in this manner for 6 months, and then that symptom left her; after which the ulcer was kept open other 6 months, when it dried up of itself naturally, with a very firm but small cicatrix. Of the Giants' Causeway* in Ireland. By the Rev. Richard Pococke,† LL.D., Archdeacon of Dublin, and F.R.S. N° 485, p. 124.

The sea-cliffs are very high thereabouts, but what is called the Causeway is a low head, extending from the foot of the cliffs into the sea like a mole. This head does not appear at first so grand as it is represented in the views engraved of it; but when one comes to walk upon it, and consider it more attentively, it appears to be a stupendous production of nature. The head ends in 2 points: Dr. P. measured the more western to the distance of 360 feet from the cliff, and it appeared to extend about 60 feet farther, which he could not measure, as the

This causeway is before taken notice of in No 199, 212, 235, and 241 of these Transactions. Orig.

+ Dr. Richard Pococke, a relation of the learned orientalist, was the son of Mr. R. P., sequestrator of the church of All-Saints in Southampton, and head master of the free-school there, where our author was born, 1704; from which school he was removed to Corpus Christi College, Oxford. Here he took his degree of LL.D. in 1733. In 1737 he began his travels to the East, where he spent 5 years, returning in 1742. The year following he published the first part of his travels; and in 1745 came out the 2d vol. of the same, which he dedicated to the Earl of Chesterfield; who being then made lord lieutenant of Ireland, Dr. P. attended him thither as domestic chaplain, by whom he was soon after appointed arch-deacon of Dublin. In the duke of Devonshire's administration he was promoted to the bishoprick of Ossory, in 1756, and to the see of Meath in 1765 by the duke of Northumberland; but the same year he died of an apoplectic fit, while on a visitation, at 61 years of age.

His Travels are justly held in great esteem. He was a great traveller, and visited other parts, as well as the East, and the course of the Nile a considerable length. He had also some other papers besides the above, in the Philos. Trans., and elsewhere. And among the manuscript treasures in the British Museum are several volumes (4811.... 4827), the gift of bishop Pococke, of curious literary and antiquarian researches.

VOL. IX.

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sea was then high: and at low tides it might be seen about 60 feet yet farther, on a descent losing itself in the sea. He also measured the more eastern point 540 feet from the cliff, and saw about as much more of it as of the other, when it winds about to the eastward, and is also lost in the water. One may walk on this head on the tops of the pillars to the edge of the water. These pillars are of all angular shapes, from 3 sides to 8. The eastern point, towards that end where it joins the rocks, terminates for some way in a perpendicular cliff, formed by the upright sides of the pillars, some of which he measured, and found to be 33 feet 4 inches in height. They say there are in all 74 different sorts of figures among them. Each pillar consists of several joints or stones lying one upon another, from 6 inches to about a foot in thickness: some of these joints are in the middle so convex, as for those prominences to be nearly quarters of spheres, round each of which is a ledge, on which the stones above them have rested, every stone being concave on the under side, and fitting in the exactest manner on that which lies next below it. The pillars are from one to 2 feet in diameter, and consist most commonly of about 40 joints, most of which separate very easily, though some others, which are more strongly indented into each other, cohere strongly enough to bear being taken away in pairs..

But the causeway is not, he thinks, the most singular part of this extraordinary curiosity, the appearance of the cliffs themselves being yet more surprising; these and their several strata he examined from the rocks on the other side of a little bay, about half a mile to the east of the causeway. He thence observed, that there runs all the way a stratum from the bottom, of black stone, to the height of about 60 feet, divided perpendicularly at unequal distances by stripes of a reddish stone, looking like cement, and about 4 or 5 inches in thickness. On this there is another stratum of the same black stone, divided from it by a stratum 5 inches thick of the red. Over this another stratum of stone 10 feet thick, divided in the same manner; then a stratum of the red stone 20 feet deep; and above that a stratum of upright pillars. Above these pillars lies another stratum of black stone 20 feet high; and above this is again another stratum of upright pillars rising in some places to the top of the cliffs, in others not so high, and in others again above it, where they are called the chimneys.

This face of the cliffs reaches for 2 computed miles east from the causeway, that is about 3 measured English miles, to the house of Mr. John Stewart, 2 miles west of Balintoy. The upper pillars seem to end over the causeway, and he thinks become shorter and shorter as one goes from it, lying between 2 binds of stone like seams of coal, and like those little pillars found in Derbyshire. These binds probably meet together all round, and inclose this extraordinary work of nature; and if so, the pillars must be very short towards the extre mities.

He was led to this conjecture by the following observations: the lower stratum of pillars is that which goes by a descent into the sea, and which makes what is called the Giants' Causeway: and where this descent approaches the sea, it seems probable that the pillars become shorter and shorter, so as to end not much farther off. Now the upper bind of this stratum may have been of so soft a nature, as by degrees, in process of time, to have been washed away by the sea. And in the cliff over the causeway are several pillars lying along in a rude manner almost horizontally, which seemed to be some of the pillars of the upper stratum fallen down by the giving way of the bind which was under them, and over the lower ones that compose the causeway. And here most probably the upper pillars ended, as they are seen no farther in the cliff. He saw the tops of pillars even with the shore, both on the east and west sides of the causeway, and some much lower than the causeway itself; and it is probable that these are much shorter than those of the causeway, which he measured above 30 feet higher than the tops of them.

When on the causeway, he saw in the cliff, to the south-east, what they call the Organs, about a quarter of a mile off, and a third part of the way up the cliff. They appeared small, and somewhat like a black stalactites: they were not commonly known to be such pillars as the others; but they are so, and belong to the lower stratum. When with great difficulty he climbed up the steep hill to them, he found they were hexagonal, and larger pillars than most of the others, being about 2 feet in diameter; and he measured 5 sides of one of them, which were of 13, 15, 12, 21, and 16 inches respectively. The joints he could come at were about 9 inches thick, and each pillar consisted of between '40 or 50 of them these joints are almost flat and plain, the convexities on their upper faces being so small as to be scarcely discernible. He inquired whether any of these pillars were found in the quarries within land, and the people there told him they were not; but he has since been assured by others, that there are some found 2 or 3 miles from the shore.

:

Of a Metalline Thermometer. By Maurice Johnson, Esq. President of the Gentlemen's Society at Spalding. N° 485, p. 128.

This machine, placed in the Gentlemen's Society of Spalding, was the invention of the late Mr. Samuel Frotheringham, a grazier at Holbeach in Elloe Holland, Lincolnshire. He and Mr. John Ingram of the same place, watch-maker and whitesmith, whose father, originally a blacksmith at Cowbitt, and inventor of the machine for cutting watch-wheels, was also a most accurate artificer, having made and fixed up in the Spalding Museum this metal thermometer, which on experience and observation, was found to answer and go truly.

This thermometer was composed of an upright bar a, fig. 4, pl. 9, of the best