are those only which can excite the muscular contractions. But as the Leyden phial, after a few explosions, ceases to emit any electric signs, in like manner the animal, after having sustained a variety of contractions, becomes altogether motionless. Nature makes use of the transition of the electric fluid in order to produce these various motions, and perhaps, also it may administer to perception. This simple theory, though countenanced by a great number of electrical phenomena, still remains without the support of perfect analogy: for if the comparison of the animal body with the Leyden phial be just, the results of experiments made with either should be similar. Now light bodies, when one end of a semi-circular conductor is applied to the ball communicating with the inside, and the other touches the outside of the Leyden phial, are known to spring up from the ball to the semi-circular conductor; a similar effect should therefore be produced in the case of the animal Leyden phials, if the expression may be allowed.

Vassali Eandi, the friend of Galvani, has no hesitation in declaring that he has frequently reiterated the experiment, varied the apparatus, and made use of the lightest bodies, such as the finest metallic leaves, without being able to ascertain with accuracy that any electrical appearances were produced. What then must be the inference? Is it to be concluded that the fluid that occasions the muscular contractions, is neither metallic nor animal electricity, but a fluid of a different kind, the nature of which is still to be explored? The ingenious author, whose name has just been mentioned, ventures not to pronounce a decisive opinion on the subject. If, however, he should dare to deliver one, it would be, that the muscular contractions are produced by the motion of the animal electrical fluid, directed by the conductors of natural electricity; for without adducing in corroboration of this opinion, the numberless experiments published by Gordini, Galvani, Volta, and many others, he would simply observe, that in the processes of nature, when any body changes its chemical state, it also admits a change in its peculiar capacity of containing the electric fluid, and even not unfrequently it changes its na

ture itself so far as it has any relation to electricity, as may be `observed in metallic oxyds.

The apparatus commonly termed the Galvanic pile, was invented by the celebrated professor Volta. Mr. Cruikshank, an ingenious Englishman, has greatly improved the means of experiments in Galvanism by the contrivance of the trough. Volta's pile is composed of a number of plates of zinc and copper, and pieces of wet cloth, all of equal size, placed one upon another; first a plate of copper, then of zinc, then a wet cloth; then of copper, zinc, and wet cloth, until a pile of twenty, forty, or sixty, or any required number of plates, is raised. The cloth should be wet with salt water, diluted muriatic acid, or some other oxydating menstruum.

With this apparatus water is decomposed in a very pleasing and easy manner. Take a narrow glass tube 5 or 6 inches long; fit each end with a cork, penetrated by a piece of slender iron wire, and fill the tube with water. Let the ends of the two wires be distant from each other, about of an inch, and let one be made to communicate with the top, and the other with the bottom of the pile. On making this communication, bubbles of air will form, and will ascend to the top of the tube; the wire being rapidly oxydated. In this experiment water is decomposed; its oxygen unites with the iron, while its hydrogen appears in the state of gas. After the apparatus has stood thus prepared about 12 hours, on uncorking the upper end of the tube, and suddenly applying a lighted candle, the hydrogen gas will take fire, and explode. with a considerable noise.

The Galvanic trough of Mr. Cruikshank is made of baked wood, wherein grooves are formed opposite each other, one tenth of an inch deep, and sufficiently wide to admit of a plate of zinc and copper, soldered together; three of these grooves are made in the space of an inch; the interstice between each pair of plates, is to be filled with an oxydating menstruum, to answer the same purpose as the wet cloths in the pile. The plates after being soldered together, are to be cemented into the grooves.

Mr. Cuthbertson, in a recent publication, has noticed some

remarkable and distinguishing properties between metallic Galvanism and electricity. When iron wire is ignited by a common electrical discharge, in such a degree as to produce a red heat through the whole length, the discharge is accompanied by a loud explosion, and the red heat produced in the wire lasts no longer than the body of the metal can retain that heat. But when produced by the Galvanic discharge, no explosion happens, and the red heat that is caused, continues for a sensible length of time, longer than when it is caused by the electric explosion. This proves that a current of Galvanic fluid follows the discharge. Déflagration of iron wire may be produced by Galvanism as well as by common electricity, so far as to form globules; but the electric discharge will disperse them to a great distance; whereas they are left at rest by the Galvanic. An electric discharge can convert iron and other metallic wires into an impalpable powder so as to float in the air; which cannot be done by Galvanism. Common electricity charges coated glass; so does Galvanism; but in a very inferior degree. Though not universally allowed, there is no doubt of this fact. Galvanism decomposes water; so does electricity; but in a very inferior degree. A double quantity of Galvanic fluid in the form of a discharge can only ignite a double length of wire; but a double quantity of electricity, in the same form, will ignite four times the length of wire. The deflagration of charcoal, which is produced by Galvanism, has never been effected by common electricity.

Galvanism has been introduced into this course, merely as it is connected with electricity, or as a modification of th same fluid. Its wonderful properties, in the hands of skilful chemists, have developed some secrets of nature, which had resisted the energies of all former powers, though they were applied by the most consummate skill, and with the most unwearied perseverance. I will only mention the discovery of the metallic bases of potash and soda, as an example in point, and refer the student for more particular information on the

VOL. II.

2

subject, to professor Davy's various works, and to the notes to the American edition of Henry's Chemistry, p. 43.

Since the astonishing discoveries of the modern English and French chemists, have been made public, little is left for communication but a detail of experiments and a repetition of them. I speak of the present moment. Our continent presents an ample field for the chemist-and we venture to predict, that our GORHAM and SILLIMAN will rival the Davys and the Lavoisiers of the elder hemisphere. Already have they availed themselves of the experience and science of Europe; and with an exhaustless mine of materials for examination, they will, not fail to realize the fond hopes, and gratify the sanguine expectations of their country.

REMARKABLE INSTANCE OF DEPRAVITY.

In a late English publication, we find the following relation of an undoubted fact, which occurred not many years ago in one of the provincial courts of Great Britain.

Two men were once convicted of highway robbery before judge Caulfield. When the jury brought in their verdict of guilty, the elder of the two fellows turned round to the younger, and with a countenance expressive of the most diabolical rage, malice, and revenge, addressed his companion in the following manner.

"Damnation seize you, you henhearted villain! If it had not been for you, I would have sent that rascal to hell, who here witnesses against us. I would have murdered the villain and then he would have told no tales. But you, you cowardly scoundrel, persuaded me to let him go-You dog, if I be hanged, you will be hanged with me, and that is the only satisfaction and comfort I have. But, good people, if any of my profession be among you, take warning by my example. If you rob a man, kill him on the spot; you will then be safe, for dead men tell no tales. I have robbed many persons, and I may escape from prison, and rob many more-and, by heavens! the man I rob, I will surely murder."

"May God visit the blood of the man you murder upon my head!" said judge Caulfield. "Go, Mr. Sheriff, procure a carpenter, have a coffin made, and a gallows erected on the very spot where that monster now stands; for from this bench I will not remove till I see him executed. As for the young man, whose heart, though corrupted by the influence of this infernal wretch, still retained the principles of humanity, he shall not perish with him. I must indeed pass upon him the sentence the law requires; but I will respite him, and use my influence with the crown, to procure his pardon. This hoary villain shall not therefore have the satisfaction his malignant heart has anticipated."

The sheriff obeyed the order; a gallows was erected in the court-house; and in the presence of the judge, the jury, and the people, the unparalleled monster ascended the scaffold, cursing and blaspheming even to the moment when he was launched into eternity.

LETTERS ON MYTHOLOGY.

TRANSLATED FROM THE FRENCH OF C. A. DEMOUSTIER.

LETTER XII.

You are well acquainted, my Emilia, with the numerous race of our modern Midas, who boast themselves to be in possession of learning and talents, which unhappily no other person can discover. These gentlemen may, with greater propriety, boast of the nobleness and antiquity of their origin; since their first father was assuredly Midas, king of Lydia, a contemporary of Bacchus. It is a pity, for the sake of our musical age, that this illustrious amateur should have been born some thousand years too soon; in the nineteenth century he would have done wonders; he would have been the oracle of our Opera-goers, the chief of our musical critics, to whom now he has only transmitted his name and his ears.

This prince having heard much of Apollo's sublime talent, exclaimed one day (resting his hand on his hip):-" Marvel