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produced at sea, and of the same colour as the mother. It must be tes membered that in this species, the young ones are entirely formed in the inlide of the animal, whence they are put forth through the mouth ; so that, whatever idea we may form to ourselves of this spea cies of beings, we can find no real analogy between any sections from them, and those torn from stems and roots of certain trees, with a view to multiply them. The young anemony we are speaking of is not large enough to favour the supposition that it had been ready for birth, in that part of the old anemony, for more than two years before ; since fome young
anemonies of this species, which I had kept in order to observe their encrease, have in ten months time grown to double the diameter of their bases, without my having ever taken the trouble to feed them: and it is besides known, that it is usual for these anemonies; when they are put to any pain, to eject all the young ones they contain.
" The restored inoiety produced another young anemony on the 7th of August, another on the 27th, one more on the 1st of September, 2 larger one on the 20th of October: whereas to this day the other half has not yet afforded me a single young one. Another circumstance worth notice is, that the two halves of the original anemony never produced any young ones, neither during their recovery, nor after their restoration."
“ Some persons, who intereit themselves in the progress of my ex periments, induced me on the 27th of June laft, to cut an anemony of the first species perpendicularly into four parts. For this purpole I chose a very large one, just taken out of the sea ; and on cutting it in that manner, it
One of these quarters adhered the next day to the side of the vafe: on the 30th it had crept to the surface of the water. It looked healthy till the middle of No. vember; but at the end of the year the wound was not yet perfectly healed: nevertheless, a few days after, it put forth a young one of a tolerable fize. The cold of the 28th of January seems to have accelerated its dissolution. The second quarter had nearly the same fate, ex cept that it yielded no young ones. The third produced, on the 6th of September, a young one of a very small size. On the 15th the wound feemed to be closed, but its place still appeared of a pale colour, transparent, and considerably depressed. On the 30th it put forth another Imall young one; and on the 26th of October, a third of a somewhat larger fize. On the 29th of January 1776, after the water had been often frozen, I saw it put forth three young ones of a moderate fizez On the 31st it produced a seventh; but since the frost it has ever appeared in a weakly itate. The fourth quarter, after several changes in its state of health, produced, on the 29th of November, three young ones; one large, the other of a middling fize, and the third very small. After the severe cold it declined: it nevertheless put forth three more young ones, and died one of the first days in March. Thus from three of thele quarters I had no less than fourteen young ones, besides the twelve the animal had produced during the operation. The interior contractions of the anemonies not only renders it difficult to cut them into four parts; but I have also observed, that those sections do not easily recover a cylindrical form, and that they are easily affected by frost or any other accident.”
Art. 8, is entitled Experiments and Observations in Electricity. By Mr. William Henly, F. R. S.
This paper is divided into two parts, the first of which contains a remarkable instance of the effect of a coating of lampblack and tar, in preserving those parts of the mast of a ship, which were covered with it, from damage by a stroke of lightning, that shivered the uncoated parts in a very extraordinary manner. This instance suggested the making of several experiments, from which Mr. Henly deduces the following corollaries.
“ ist, That a charge of electricity, or a stroke of lightning, which is the same thing, passes, in many cases, upon the surface of bodies, in a much larger proportion than through the interior fubstance of them, as appears by the masts of ships, coated with lamp-black, &c. *, and by the experiment above recited, with the cylinder of ivory and the glass, &c.; for in this experiment, the charge being retifted by the ivory (which however is sometimes split by the explosion) forces a paslage between that and the glass, and being there confined by heavy weights, exerts its expansive power in such manner as to reduce to the smallest fragments the plate of glass then exposed to its violent operation. 2dly, This violent effort of the electricity produces not the least effect upon the surface of the flip of paper painted with lamp-black and oil, or upon a flip of oiled filk, placed in the same situation. 3dly, May not therefore a coating of lamp-black and tar, or lamp-black and oil, be in some cases usefully applied on flight buildings of wood, &c. to preserve them from damage by lightning, as well as to prevent those large cracks and rents (the usual etfect of the heat of the sun) from being made in them? 4thly, As the effect of the lightning on the masts of ships has been in so many instances prevented by a coating of lamps black and tar, or lamp-black and oil, it seems probable, that a safe and fixed conductor might be applied to them in a very cheap and convenient manner, as follows ; viz. let all those parts of the mait which are usually greased, be provided with plates of metal three inches broad, which plates might extend a few inches upon the other parts of the malt which are coated with lamp black and tar, or lamp-black and oil; and thus by the conductor of metal, and the protector of lamp-black and tar, placed alternately and extending the whole length of the mast, it would probably be preserved from damage by lightning. A metallic communication might be made from the mait to the water in the manner I have before mentioned, in Phil. Trans. vol. LXIV. p. 412. This method of making conductors to ships, from its fimplicity and practicability, I had some thoughts of recommending to my acquaintance in the marine department; but there is one objection to it, which I think a very material one, and Ahall therefore state it in its full force: it is this; the lamp-black and tar, or lamp-black and oil, though they protect, by their property of repelling the electric matter, thote parts of the mást which are coated with them, yet being perfect non-con
See a curious instance of this kind in M. Adanson': Voyage to Senegal, P. 239. Vol. VI.
ductors, those things or persons which might happen to ftand in their vicinity (as in the tops, &c.) would be in danger of a fevere stroke, perhaps defiruction, by the lightning. How far the other oil colours, viz. those prepared from minerals and metals, may answer these purposes, may perhaps deserve enquiry, and the more fo, as the experi, ients are not difficult to make. The belfry-pots painted with white lead, mentioned in the letter above recited, were much shivered. Sthly, As oiled filk seems to be so good a security againit the effects of a charge of electricity, may not garments, viz. cloaks and hats, covered with that substance, contribute in some measure to protect the wearers (it overtaken by a storm) from a stroke of lightning?”
Part the ad of this article relates to the electricity of chocolate, with other experiments; concluding with theoretical conjectures on the nature and properties of electricity, considered as a physical principle.
" It is a question,” says Mr. Henly," that hath been frequently put to electricians, WVhat is electricity? For my own part, I have generally chosen (perhaps for want of a better answer) to reply by a similar question, vis. What is air? or, what is water? For, as these are understood to be fluids distinct from all others, and distinguished by the names they bear, so have I ever considered electricity as a fluid fui generis, and properly characterised by the term electricity, electric fluid, or electric matter; and have always avoided the term electric fire, as conveying a confused idea of actual inflammation, burning, &c. : but I now begin really to doubt, whether another appellation might not be applied with greater propriety; whether electricity may not be confidered as a pure, ethereal, elementary fire, inherent in all bodies, intiiately connected or blended with an earthy or other base, and apparently, though not actually, remaining in it in a quiescent state, till soused into action by some proper application, as motion, or rather friction, which may, and probably does, collect it in our experiments. (But can motion convey initantaneously that which is not material, but only a quality, a property, an accident, or affection, of matter, through fach circuits as those of Dr. Watson, and produce such astonishing effcēts at the interruption of those circuits ? Besides, in Dr. Franklin's moft curious and decisive experiment of charging the Leyden bottle with its own electricity, the glass undergoes no friction whatsoever; but the electricity inherent in it is simply exhausted from one of its surfaces, and forced round upon the other by the electrical apparatus: the same may be asserted of bodies presented toward a conductor negatively electrified, or to the insulated rubber of the electrical machine.) That it may be faid to reside in vegetables, and is extracted together with their oil; that in fermentation, effervescence, and putrefaction, it flies off in the phlogittic vapour thence arifing; that in distillation it is disengaged and brought over in an ardent spirit, in which it resides, retaining its original properties in a purer base; that, since by the collision of fint, iteel, &c. actual fire is inftantaneously produced (as in the instance of the dry axle of a carriage, which, by the friction of the wave against it, toon takes re) so by the friction of other bodies, which by long perieverance would produce the same effect,
this latent fire may be first excited, and its appearances, though unobserved, be those we term electrical. A wind-mill, when it works une der the break (as the millers térm it when no iron is concerned) foon catches fire (the mill-Itones, when no corn is berwcen them, produce the fame effect, though the motion be the same in both cales) and many a mill hath been consumed by this means. The method used by the Indians, of producing fire by the friction of two pieces of wood against each other is well known; and in all these cales may not the first effects of the latent fire, thus roused into action, be the production of those very appearances we call electrical?
« This thought, I confess, remained so strongly impressed upon my mind, that I requested some of my friends, who had a better opportunity than myself, to make the trial. For this purpose fome pieces of wood were baked in an oven, in order to expel the moisture, and prepare them for the experiment. When they were cooled, a friction was begun, which, as I expected, soon produced electricity; one piece of the wood being excited positively, the other negatively, as I have fince myself several times experienced. Had the friction been continued, the production of actual fire might perhaps have been the consequence. May not, therefore, the production of actual fire be the ultimum of electricity? or, in other words, electricity the first effect of Jatent fire thus roused into action ; actual fire, the second; and inflammation and dissolution, its third and greatest effort ? like fermentation, producing first, wine ; fecondly, vinegar; laitly, putrefaction. To give some countenance to this supposition, let fore of the effects of electricity and fire be placed in a comparative view. First, a finall iron wire, held in the flame of a candle till it acquires a white heat, will frequently burst into little balls, flying off in all directions. The same effect is produced by a flint and steel ; and in a superior manner, by a strong charge of electricity, or a flash of lightning passing through such a small wire; the balls then appearing, on examination, to be little more than the scorice of the metal. The effect of electricity, lightning, and fire, in destroying the power of the artificial or natural magnets, is a circumstance that hath been often remarked, and repeatedly published. The effects of electricity, in common with fire, on prout-Spirit, gun-powder, phosphorus, dry lint, and many other subitances, must occur to every gentleman conversant in these experiments ; indeed the parallel might be continued much further. But may be asked, if this be really the fact, should not metals become electrical by friction? I answer, they are readily excited, provided they be first
properly insulated (but if metal be rubbed against metal, the phlogiston or latent fire, if I may be allowed the expression, is so nearly proportioned in the two metals, that the equilibrium is restored as foon as destroyed, from the very nature of the base, which is the molt perfect conductor we are acquainted with): to illustrate this, let it be remembered, that though the hydrostatic paradox may be readily explained, yet the fluid muit be confined in a proper vessel; and though the weight, the spring, and the compressibility of the air, be casily demonstrable, a suitable apparatus muit neceffarily be employed for each purpose. It is a question by no means decided, how the clouds become electrified? But if we suppose the electric matter to be
a pure, ethereal, elementary fire, resident in all bodies; that the great process of vegetation is carried on by means of this subtile, active, volatile, and pervading element; that it is continually exhaling from all the vegetable tribe ; that as evaporation is a remarkable agent in the cooling of heated substances, that is, a good conductor of their fire, as I am well assured it is of electricity; may we not conclude, that this is one great cause of the clouds becoming at times furcharged with this fluid? The great effect of electricity in promoting vegetation, hath been fully proved by Dr. De Maimbray, the Abbé Ñollet, Mr. Jallabert, and other gentlemen, and was very remarkable in that year when the fatal earthquake happened at Lisbon. Dr. Stukeley's observations on the frequent appearances of fire-balls, corufcations, and aurora boreales, at this time (which I well remember) deserve to be particularly noticed; and it is generally remarked, that thunderstorms are preceded by a continuance of hot weather, and that a moderate tempe. rature inmediately succeeds the storm. The remarks and observations of the wortby Dr. Hales on this subject seem also to merit peculiar attention. Further, as the rays of the sun, concentrated by a powerful burning inirror, will produce a fusion of metals, and instantly reduce a number of substances presented to the focus to a calx, as the same effect is in many cases produced by a stroke of lightning; and as the colours of the electric and solar light are equally divisible by the prism; may not these also bear some kind of relation to each other? Upon the whole, is there not an high degree of probability in the supposition, that light, fire, phlogiston, and electricity, are only different modifi. cations of one and the fame principle? A fimilarity in several of the phenomena of electricity and magnetism hath been long fince pointed out by Dr. Price, from M. Æpinas ; and the effect of heat on both admirably displayed by Mr. Canton. Of all the substances I have yet examined, the most difficult to excite, I observed to be a fine, smooth, unarmed load-stone, and a piece of black lead; these seemed to bid defiance to all my rubbers: at length, however, with a piece of new Aannel they were both excited, in a very small degree, negatively. In short, I have not yet met with a single article fon which the experiment could be tried) that I could not, with one or other of my rubbers, make in fome degree electrical. The laws by which all these Muids are governed, and what constitutes the precise difference between rhem, may yet, perhaps, by some fortunate philosopher, by a train of just reflexion, and a set of happily contrived and well-conducted experiments, be much farther elucidated. Lastly, I do not speak of these things as facts of which I am absolutely convinced; but earnestly with to recommend them to the serious confideration of future enquirers. From what hath been said, however, I apprehend it will scarcely be doubted, that electricity, whatever it be (as I have often remarked) is one of the greatest and most important agents in the operations of Nature; that the effects of lightning, therefore, are but as difcords in her harmony; and, though singly considered, they may appear unpleasing notes, yet perhaps may be necessary to fill up and compleat her grand and general chorus."
Delighted as we are with the chemical discoveries of the present age, and sensible of the ingenuity of the discoverers