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"14. Muriatic acid positively polarized loses its peculiar voltaic condition by being mixed with some chlorine, and the same acid being negatively polarized loses its polarity by being treated with some hydrogen. From the facts stated, and others which are mentioned in the memoir above alluded to, a great number of rather important inferences might be drawn; but having for the present no leisure time to do so, I am obliged to confine myself to stating those which follow:

"a. The secondary currents produced both by polar wires, electrolytic fluids, and secondary piles, are due to chemical action, i.e. (in the cases mentioned), to the union of oxygen with hydrogen, or to that of chlorine with hydrogen; and not as M. Peltier seems to think, to the mere act of the solution in water of the gasses mentioned.

"b. The chemical combination of oxygen and hydrogen in acidulated (or common) water is brought about by the presence of platina in the same manner as that metal determines the chemical union of gaseous oxygen and hydrogen.

"c. The current produced by a platina wire being surrounded by a film of chlorine, or by water holding chlorine in solution, is not dependent on the action of the latter body upon platina, but on the action of chlorine upon the hydrogen of water.

"d. Electrotytic bodies do not suffer even the weakest current to pass through them without undergoing decomposition. This inference is drawn from the fact ascertained by me some time ago, that platina wires, acting as electrodes in muriatic acid, are polarized by a current so weak as not to be able to electrolyze even iodide of potassium.

"e. The most delicate test to ascertain that electrolyzation has taken place, is the polarized state of the electrodes.

"I cannot close this communication without pointing out the beautiful, and, as it seems to me, most conclusive evidence in favour of the correctness of the chemical theory of galvanism, now so much contested, which is afforded by the fact stated in § 10. If the mere contact of the two different fluids mentioned there, were the real cause of the current obtained, it is obvious that the same current ought to be produced whether the fluid be connected with the galvanometer by means of gold, or if they be connected with the instrument by that of platina wires; but the result being determined by the nature of the connecting wires, and platina being known to favour the union of hydrogen and oxygen, whilst gold and silver do not possess in any sensible degree that property, we are entitled to assert that the current in question is caused by the combination of hydrogen with [the] oxygen [contained dissolved in water], and not by contact."

The last paper of Professor Schöenbein's on these subjects, that we shall have to notice, will be found at page 285, vol. vii, of these "Annals."

Bale, December, 1838.

Observations and Suppositions towards forming a new Hypothesis for explaining the several Phenomena of Thunder Gusts. By Dr. FRANKLIN.

1. NON-ELECTRIC bodies that have electric fire thrown into them, will retain it till other non-electrics that have less approach; and then it is communicated with a snap, and becomes equally divided. 2. Electrical fire loves water, is strongly attracted by it, and they can subsist together.

3. Air is an electric per se, and when dry will not conduct the electrical fire; it will neither receive it, nor give it to other bodies; otherwise no body surrounded by air, could be electrified positively and negatively for should it be attempted positively, the air would immediately take away the overplus; or negatively, the air would supply what was wanting.

4. Water being electrified, the vapours arising from it will be equally electrified; and floating in the air, in the form of clouds, or otherwise, will retain that quantity of electrical fire, till they meet with other clouds or bodies not so much electrified, and then will communicate as before-mentioned.

5. Every particle of matter electrified is repelled by every other particle equally electrified. Thus the stream of a fountain, naturally dense and continual, when electrified, will separate and spread in the form of a brush, every drop endeavouring to recede from every other drop. But on taking out the electrical fire they close again.

6. Water being strongly electrified (as well as when heated by common fire), rises in vapours more copiously, the attraction of cohesion among its particles being greatly weakened, by the opposite power of repulsion introduced with the electrical fire; and when any particle is by any means disengaged, it is immediately repelled, and so flies into the air.

7. Particles happening to be situated as A and B, Fig. 5, Pl. II, representing the profile of a vessel of water, are more easily disengaged than c and D, as each is held by contact with three only, whereas c and D are each in contact with nine. When the surface of the water has the least motion, particles are continually pushed into the situation represented by A and B.

8. Friction between a non-electric and an electric per se, will produce electrical fire; not by creating, but collecting it: for it is equally diffused in our walls, floors, earth, and the whole mass of common matter. Thus the whirling glass globe, during its friction against the cushion, draws fire from the cushion, the cushion is supplied from the frame of the machine, that from the floor on which it stands. Cut off the communication by thick glass or wax,

• Thunder gusts are sudden storms of thunder and lightning, which are frequently of short duration, but sometimes produce mischievous effects.

placed under the cushion, and no fire can be produced, because it cannot be collected.

9. The ocean is a compound of water, a non-electric, and salt, an electric per se.

10. When there is a friction among the parts near its surface, the electrical fire is collected from the parts below. It is then plainly visible in the night; it appears at the stern and in the wake of every sailing vessel; every dash of an oar shews it, and every surf and spray in storms the whole sea seems on fire. The detached particles of water then repelled from the electrified surface continually carry off the fire as it is collected; they rise and form clouds, and those clouds are highly electrified, and retain the fire till they have an opportunity of communicating it.

11. The particles of water rising in vapours, attach themselves to particles of air.

12. The particles of air are said to be hard, round, separate and distant from each other; every particle strongly repelling every other particle, whereby they recede from each other, as far as common gravity will permit.

13. The space between any three particles equally repelling each other, will be an equilateral triangle.

14. In air compressed these triangles are smaller; in rarified air they are larger.

15. Common fire joined with air increases the repulsion, enlarges the triangles, and thereby makes the air specifically lighter. Such air, among denser air, will rise.

16. Common fire, as well as electrical fire, gives repulsion to the particles of water, and destroys their attraction of cohesion; hence common fire, as well as electrical fire, assists in raising vapours.

17. Particles of water having no fire in them, mutually attract each other. Three particles of water then being attached to the three particles of a triangle of air, would by their mutual attraction operating against the air's repulsion, shorten the sides and lessen the triangle, whereby that portion of air made denser would sink to the earth with its water, and not rise to the formation of a cloud.

18. But if every particle of water attaching itself to air, brings with it a particle of common fire, the repulsion of the air being assisted and strengthened by the fire, more than obstructed by the mutual attraction of the particles of water, the triangle dilates, and that portion of air, becoming rarer and specifically lighter, rises.

19. If the particles of water bring electrical fire when they attach themselves to air, the repulsion between the particles of water electrified, joins with the natural repulsion of the air, to force its particles to a greater distance, whereby the triangles are dilated, and the air rises, carrying up with it the water.

20. If the particles of water bring with them portions of both sorts of fire, the repulsion of the particles of air is still more strengthened and increased, and the triangles farther enlarged.

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21. One particle of air may be surrounded by twelve particles of water of equal size with itself, and in contact with it; and more added to those.

22. Particles of air thus loaded, would be drawn nearer together by the mutual attraction of the particles of water, did not fire, common or electrical, assist their repulsion.

23. If air thus loaded, be compressed by adverse winds, or by being driven against mountains, &c., or condensed by taking away the fire that assisted it in expanding, the triangles contract, the air with its water will descend as a dew; or, if the water surrounding one particle of air comes in contact with the water surrounding another, they coalesce and form a drop, and we have rain.

24. The sun supplies (or seems to supply) common fire to vapours, whether raised from earth or sea.

25. Those vapours which have both common and electrical fire in them, are better supported than those which have only common fire in them; for when vapours rise into the coldest region above the earth, the cold will not diminish the electrical fire, if it doth the

common.

26. Hence clouds formed by vapours raised from fresh waters within land, from growing vegetables, moist earth, &c., more speedily and easily deposit their water, having but little electrical fire to repel and keep the particles separate. So that the greatest part of the water raised from the land, is let fall on the land again; and winds blowing from the land to the sea are dry, there being little use for rain on the sea, and to rob the land of its moisture in order to rain on the sea, would not appear reasonable.

27. But clouds formed by vapours raised from the sea, having both fires, and particularly a great quantity of the electrical, support their water strongly, raise it high, and being moved by winds, may bring it over the middle of the broadest continent from the middle of the widest ocean.

28. How these clouds so strongly supporting their water, are made to deposit it on the land, where it is wanted, is next to be considered.

29. If they are driven by winds against mountains, those mountains being less electrified attract them, and on contact take away their electrical fire, and being cold their common fire also; hence the particles close towards the mountains and towards each other. If the air was not much loaded, it only falls in dews on the mountain tops and sides, forms springs, and descends to the vales in rivulets, which united, make larger streams and rivers. If much loaded, the electrical fire is at once taken from the whole cloud; and, in leaving it, flashes brightly and cracks loudly; the particles instantly coalescing for want of that fire, and falling in a heavy shower.

30. When a ridge of mountains thus dams the clouds, and draws the electrical fire from the cloud first approaching it, that which next

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follows, when it comes near the first cloud, now deprived of its fire, flashes into it, and begins to deposit its own water; the first cloud again flashing into the mountains; the third approaching cloud, and all succeeding ones acting in the same manner, as far back as they extend, which may be over many hundred miles of country.

31. Hence the continual storms of rain, thunder and lightning, on the east side of the Andes, which running north and south, and being vastly high, intercept all the clouds brought against them from the Atlantic ocean by the trade winds, and oblige them to deposit their waters, by which the vast rivers Amazons, La Plata, and Oroonoko are formed, which return the water in the same sea, after having fertilized a country of very great extent.

32. If a country be plain, having no mountains to intercept the electrified clouds, yet it is not without means to make them deposit their water. For if an electrified cloud coming from the sea, meets in the air a cloud raised from the land, and therefore not electrified, the first will flash its fire into the latter, and thereby both clouds shall be made suddenly to deposit water.

33. The electrified particles of the first cloud close when they lose their fire; the particles of the other clouds close in receiving it: in both they have thereby an opportunity of coalescing into drops. The concussion or jerk given to the air, contributes also to shake down the water, not only from those two clouds, but from others near them. Hence the sudden fall of rain immediately after flashes of lightning.

34. To shew this by an easy experiment: take two round pieces of pasteboard two inches diameter; from the centre and circumference of each of them suspend by fine silk threads eighteen inches long, seven small balls of wood, or seven peas equal in goodness; so will the balls appending to each pasteboard form equal equilateral triangles, one ball being in the centre, and six at equal distances from that, and from each other, and thus they represent particles of air. Dip both sets in water, and some adhering to each ball, they will represent air loaded. Dexterously electrify one set, and its balls will repel each other to a greater distance, enlarging the triangles. Could the water supported by seven balls come into contact, it would form a drop or drops so heavy as to break the cohesion it had with the balls, and so fall. Let the two sets then represent two clouds, the one a sea cloud electrified, the other a land cloud. Bring them within the sphere of attraction, and they will draw towards each other, and you will see the separated balls close thus the first electrified ball that comes near an unelectrified ball by attraction joins it, and gives it fire; instantly they separate, and each flies to another ball of its own party, one to give, the other to receive fire; and so it proceeds through both sets, but so quick as to be in a manner instantaneous. In the cohesion they shake off and drop their water, which represents rain.

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35. Thus when sea and land clouds would pass at too great a dis

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