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deprived of its air to a very great degree, yet the fishes put into it did not so much as once ascend in it; but continued always at the bottom, as those did in the common water. At this time I left them till the next morning; when, about eight o'clock, I found them as lively in all the glasses as when first put in.
From the whole account I observe, 1st, That water deprived of air, so far as the method here made use of is capable to do it, renders it not altogether unfit to support the lives of water animals. For though when the fish were first put in, and for some hours after, they seemed to suffer some uneasiness, yet, at length the water became more familiar to them, or their constitutions in some measure did so conform, as to render the water to them, and them to the water, more agreeable : otherwise I do not see how their recovery should follow, since on examination little or no alteration could be found in the circumstances of the water, from the time the fish were first put in.
2dly, The fish included with their water from any communication with the external air plainly demonstrate, that common water in its natural state is not, alone, sufficient to preserve the lives of its natural animals. Hence it follows, that in ponds, when the water comes to be frozen over with a pretty thick ice, the fish in such ponds are very likely, if not certain, to perish, on the continuance of such a congelation for some time on their surfaces; unless (as in the latter part of the experiments) the impediment, which hindered the immediate contact of the air with the surface of the water, be removed; that is, by breaking holes in the ice, by which it is restored, and undoubtedly will perform the same thing as my removal of the brass plate. This is to be understood only in ponds, where the water is stagnant; for where there are springs, or a current of water constantly succeeding under the ice, the effect most likely will not be the same,
A Burning Spring at Broseley, in Shropshire. By Mr. RD.
Hopton. — [1712.] ' The famous boiling well at Broseley, near Wenlock, in the county of Salop, was discovered about June, 1711. It was first announced by a terrible noise in the night, about two nights after a remarkable day of thunder : the noise awaked several people in their beds, that lived hard by; who coming to a boggy place under a little hill, about 200 yards from the river Severn, perceived a surprising rumbling and shaking in
the earth, and a little boiling up of water through the grass. They took a spade, and digging up some part of the earth, immediately the water flew up a great height, and a candle that was in their hand set it on fire. To prevent the spring being destroyed, an iron cistern is placed aboùt it, with a cover to be locked, and a hole in the middle, through which the water may be viewed. If a lighted candle, or any thing of fire be put to this hole, the water immediately takes fire, and burns like spirit of wine, or brandy, and continues so long as the air is kept from it; but by taking up the cover of the cistern, it quickly goes out. The heat of this fire much exceeds the heat of any fire I ever saw, and seems to have more than ordinary fierceness in it.
Some people out of curiosity, after they have set the water on fire, have put a kettle of water over the cistern, and in it green peas, or a joint of meat, and cooked it much sooner than over any artificial fire that can be made. If there be put green boughs, or any thing else that will burn, upon it, it presently consumes them to ashes. The water of itself is as cold as any water I ever felt; and what is remarkable, as soon as ever the fire is out, if the hand be put into it, it feels as cold as if there had been no such thing as fire near it.
Observations on the Subterraneous Trees in Dagenham, and
other Marshes, bordering on the River Thames. By the Rev. Mr. W. DERHAM, F.R.S.- [1712.]
BETWEEN four and five years ago, there happened an inundation at Dagenham and Havering marshes, in Essex, by a breach in the Thames wall, at an extraordinarily high tide ; and by means of the great violence of the water, a large channel was torn up, or passage for the water, of 100 yards wide, and 20 feet deep in some places; in some more, some less.
By which means a great number of trees were laid bare.
The trees were all of one sort, excepting only one, which was a large oak, with the greatest part of its bark on, and some of its head and roots. The rest of the trees are by most persons taken to be yew; but a very ingenious gentleman convinced me they might more probably be some other wood, as alder, which grows plentifully by our fresh-water brooks, or else hornbeam.
By lying so long under ground, the trees are become black and hard, and their fibres are so tough, that one may as easily break a wire of the same size as any of them. They maintain this toughness, if the wood be kept dry. But by drying, the trees become cracked, and very Aawy within, but look sound outwardly, and with difficulty yield to wedges.
There is no doubt but those trees grew in the place where they now lie, and that in vast multitudes, as they lie so thick upon, or near each other, that in many places I could step. from one to another. And there is great reason to think, that not only the marshes, which are now overflown, which are about 1000 acres, are stored with those subterraneous trees, but also all the marshes along by the river side, for several miles: for we discover these trees all along the Thames side, over against Rainham, Wennington, Purfleet, and other places; and in the breach that happened at West-Thorrock, about 21 years ago, they were washed out in as great numbers and of the same kind of wood, as those found lately in Dagenham and Havering Levels.
Most of the trees that I met with had their roots on, and many of them their boughs, and some a part of their bark. There was only one that I perceived had any signs of the axe, and its head had been lopped off. As I passed the channel which the water had torn up, I could see all along the shores vast numbers of the stumps of those subterraneous trees, remaining in the very same posture in which they grew, with their roots running some down, some branching and spreading about in the earth, as trees growing in the earth commonly do. Some of those stumps I thought had signs of the axe, and most of them were flat at top, as if cut off at the surface of the earth; but being rotten, and battered, I could not fully satisfy myself, whether the trees had been cut or broken off.
The soil in which all those trees grew was a black, oozy earth, full of the roots of reed; on the surface of which oozy earth the trees lay prostrate, and over them a covering of grey mould, of the same colour and consistence with the dry sediment, or mud, which the water leaves behind it at this day. This covering of grey earth is about seven or eight feet thick, in some places 12 feet or more, in some less ; at which depths the trees generally lie. The trees lay in no kind of order, but some this way, some that, and many of them across : only in one or two places, I observed they lay more orderly, with their heads for the most part towards the north, as if they had been blown down by a southerly wind, which exerts great force on that shore.
Strata of Earth, Stone, Coal, &c. found in a Coal-Pit at the West End of Dudley, in Staffordshire. By Mr. BellERS. 1. A yellowish clay, immediately under the turf. 2. A bluish clay.
3. A bluish hard clay, called by the miners clunch. This is one of the certain signs of coal. It has in it mineral plants.
4. A bluish soft clay.
5. A fine-grained grey stone; it lies next the former, and is found in some pits only.
6. A clay almost like the first, only whiter.
7. A hard grey rock, with something like the impressions of vegetables, but none distinct.
8. A blue clunch, like No. 3.,' with mineral plants in it; 8, +, this stratum, which is the same with No. 13., was not taken.
9. Coal, called bench-coal. 10. Coal, less black and shining than the former, called slipper-coal.
11. Coal, more black and shining, called spin-coal.
12. A coal, like cannal-coal, by the miners called stonecoal. These strata of coal have between each of them a bat, of about the thickness of a crown piece.
13. A black substance, called the dun-row-bat. 14. A hard grey iron-ore, called the dun-row-iron-stone.
15. A bluish bat, in which the following iron-stone lies, called the white-row.
16. A hard blackish iron-ore, lying in small nodules, having between them a white substance, and from thence by the miners called the white-row-grains, or iron-stone.
17. A hard grey iron-ore, with some white spots in it, called the mid-row-grains.
18. A black fissile substance, called the gublin-bat.
19. A hard blackish iron-ore, with white spots in it, called the gublin-iron-stone.
20. A bat, in substance much like that of No. 18.
21. A hard grey įron ore, called the cannoc, or cannotiron-stone.
22. A bat, somewhat harder than No. 20.
23. A dark, grey, hard iron-ore, called the rubble-ironstone.
24. The table-bat, next under the rubble-iron-stone.
28. A substance like a coarse coal, but by the miners called a bat; perhaps because it does not burn well.
29. The bench-coal.
30. A bat under the last, and is as low, viz. 1884 feet, as they generally dig, though there is a coarse coal under this.
Some further Microscopical Observations on the Animalcula found on Duck-weed, 8c. By Mr. LEUWENHOEK.-[1713.)
The latter end of July, and beginning of August, I caused some of those green weeds, commonly called duck-weed, to be taken out of the water, that runs with a gentle stream through the town (Delft), for the pleasure of observing these animalcula, with others of several sorts, that were fastened to the duck-weed, or ran about upon it. Among others, I have found some animalcula, whose sheaths, at the extreme part, were a little thicker than a head hair, and composed of small globules, which were very easy to be distinguished.
I viewed one of these animalcula a good while together, and observed several times, one after another, that when the animalculum thrusts its body out of the sheath, or case, and that the wheel-like or indented particles moved in a circle, at the same time, out of a clear and transparent place, a little round particle appeared, which, without nicely viewing, could hardly be perceived; which particle growing larger, moved with great swiftness, as it were, about its own axis, and continued without any alteration in its place, till the ani. malculum had drawn part of its body back into its sheath; in doing which, it placed the said round particle on the edge of its sheath, which thus became augmented with a round globule: and whereas the animalculum had placed the said globule on the east part of its sheath, another time it fixed it on the south or north side ; by which means the sheath was regularly increased on all sides.
Having further, and with great exactness, viewed the circulating indented wheel-work, I observed that it caused an exceedingly great motion in the water about it; by which means many very small particles, which were only visible through the microscope, were wafted to the said animalculum, and others were driven away. The animalculum made use of some of these particles, that were thus drawn to it by its circulating instrument, for food and nourishment; and other particles that were thus drawn to it were with great nim. bleness driven away, and as if rejected by the animalculum : from whence I inferred, that those particles which were thus