vanizing of criminals after execution. In 1811, at Glasgow, a noted chemist tried the effect of a voltaic "pile" of two hundred and seventy pairs of plates upon the body of a murderer. As the various parts of the nervous system were subjected to the current, the most startling results followed. The The whole body shuddered as with cold; one of the legs nearly kicked an attendant over; the chest heaved, and the lungs inhaled and exhaled. At one time, when all the power of the instrument was exerted, we are told that "every muscle of the countenance was simultaneously thrown into fearful action. Rage, horror, despair and anguish, and ghastly smiles, united their hideous expression on the murderer's face, surpassing far the wildest representations of a Fuseli or a Kean. At this period several of the spectators were obliged to leave the room from terror or sickness, and one gentleman fainted." The bodies of horses, oxen, and sheep were galvanized, with results the most surprising. Five men were unable to hold the leg of a horse subjected to the action of a powerful battery.

So far as we know, nothing of much importance has yet been inferred from such experiments as these. Davy and Faraday, however, and their pupils, did not confine their attention to these barren wonders. Sir Humphry Davy took the "pile" as invented by Volta, in 1800, and founded by its assistance what may be styled a new science, and developed it to the point where it became available for the arts and utilities of man. The simple and easy process by which silver and gold are decomposed, and then deposited upon metallic surfaces, is only one of many ways in which the galvanic battery ministers to our convenience and pleasure. If the reader will step into a manufactory of plated ware, he will see, in the plating-room, a trough containing a liquid resembling tea as it comes from the teapot. Avoiding scientific terms, we may say that this liquid is a solution of silver, and contains about four ounces VOL. XX.

NO. 122.

47

of silver to a gallon of water. There are also thin plates of silver hanging along the sides of the trough into the liquid. The galvanic battery which is to set this apparatus in motion is in a closet near by. The vessels to be plated, after being thoroughly cleaned and exactly weighed, are suspended in the liquid by a wire running along the top of the trough. When all is ready, the current of electricity generated by the small battery in the closet is made to pass through the trough, and along all the metallic surfaces therein contained. When this has been done, the spectator may look with all his eyes, but he cannot perceive that anything is going on. There is no bubbling, nor fizzing, nor any other noise or motion. The long row of vessels hang silently at their wire, immersed in their tea, and nobody appears to pay any attention to them. And so they continue to hang for hours, for five or six or seven hours, if the design is to produce work which will answer some other purpose than selling. All this time a most wonderful and mysterious process is going on. That gentle current of electricity, noiseless and invisible as it is, is taking the silver held in the solution, and laying it upon the surfaces of those vessels, within and without; and at the same time it is decomposing the plates of silver hanging along the sides of the trough in such a way as to keep up the strength of the solution. We cannot recover from the wonder into which the contemplation of this process threw us. There are some things which the outside and occasional observer can never be done marvelling at. For our part, we never hear the click of a telegraphic apparatus without experiencing the same spasm of astonishment as when we were first introduced to that mystery. The beautiful manner, too, in which this silvering work is done! The most delicate brush in the most sympathetic hand could not lay on the colors of the palette so evenly, nor could a crucible melt the metals into a completer oneness.

And here is the opportunity for

fraud. In five minutes an article is coated with silver in every part, inside and out; and that mere "blush" of silver, as the platers term it, will receive as brilliant a polish, and look as well (for a month) as if it were solid plate. Nay, it will look rather better; since the silver deposited by this exquisite process is perfectly pure, while the silver employed in solid ware is of the coin standard, - one tenth alloy. The plater can deposit upon his work as little silver as he chooses, either by weakening his solution, or by leaving the articles in it for a very short time; and no man can detect the cheat with certainty except by an expensive and troublesome process. Nor will it suffice for the operator to attend to the strength of his solutions, and keep his eye upon the clock. As in certain conditions of the atmosphere we can scarcely get a spark from the electrical machine, so there are times when the galvanic battery works feebly, and when the silvering goes on much more slowly than usual. To guard against errors from this cause, there is no sure resource but a system of careful weighings. In such establishments as that of the Gorham Company of Providence, Tiffany's or Haughout's of New York, Bailey's of Philadelphia, and Bigelow Brothers and Kennard's, or Palmer and Batchelder's, of Boston, each article is weighed before it is immersed in the solution, its weight is recorded, and it is allowed to remain in the solution until it has taken on the whole of the precious metal it was designed to receive.

There was a lawsuit the other day in New York, which turned upon the quantity of silver deposited upon sundry gross of forks and spoons. The plater agreed to put upon them twelve ounces of silver to the gross, which is about as much as is ever deposited upon spoons or forks.

If he had performed his contract, he would have spread over each table-spoon about as much silver as there is in a ten-cent piece; and such is the nature of silver that these spoons would have worn

well for five or six years. In fact, there are no better plated spoons yet in use than these were designed to be. The plater meant to comply with the usages of the trade. He meant to put upon those spoons the quantity of silver which, in the trade, stands for twelve ounces to the gross, which is about ten ounces to the gross. Such was probably his virtuous intention, and he supposed he had carried out that intention. But when the spoons were put to the test, it was discov ered that upon one hundred and fortyfour table-spoons there were but three ounces and a half of silver. It came out on the trial that the plater never weighed his work, and trusted wholly to the length of time he left it in the solution. He appeared to be honestly indignant at the testimony showing that his spoons, which had been left four hours subject to the action of the battery, had acquired only a film of silver. To the eye of the purchaser, these spoons would have presented precisély the same appearance as the best plated ware in existence. For two or three months, or even for six months, they would have retained their brilliancy. What their appearance would have been at the end of a year or two we need not say, for most readers have encountered the spectacle in their pilgrimage through a world which is said to resemble plated articles of this quality in being "all a fleeting show."

Every one is familiar with the gold lining that is now so generally seen in silver vessels. This is laid on by the same process as that which covers the outside with silver. The vessel is filled with a solution of gold, and in this solution a thin plate of gold is suspended. The electric current being made to pass through the interior thus prepared, the liquid bubbles up like soda-water, and in three or four minutes enough gold is deposited upon the inside surface for the purpose designed. When this is accomplished, nothing remains but to polish the vessel, within and without, and we have

a piece of ware which is silver when we look at it, and golden when we drink from it.

The obstacle to the introduction of the superior plated ware now made by the Gorham Company is its costliness. The best plated ware costs five times as much as the worst, and one fourth as much as solid silver. We saw the other day three large salvers, which, at a distance of six feet, looked very nearly alike. All of them bore a most brilliant polish, and all were elaborately decorated. One of them was a trashy article, made of an alloy of lead and tin, covered with a "blush" of silver. It had been stamped out and shaped at one blow by a stamping-machine, and left in the silver solution subject to the action of the battery for perhaps fifteen minutes. It was very heavy, and when it was suspended and struck it gave forth a dull leaden sound. The price of this abomination was thirty-seven dollars and a half, and it would last, with careful occasional usage, for a year. Daily use would disclose its real quality in a few weeks. Another of these salvers was of solid silver, to which no objection could be made except that its price was nine hundred and fifty dollars. The third was of that superior plated ware introduced recently by the Gorham Company of Providence. The base of this article was the metal now called nickel silver, a mixture of copper, nickel, and zinc, -a very hard and ringing compound, perfectly white, and capable of a high polish. Upon this hard surface as much silver had been deposited

as upon the best Sheffield plated ware, which is about as much as can be smoothly put upon it by the electroplating process. When this salver was struck, it rang like a bell, and it would not bend under the weight of a man. Such a salver, used continually, will retain its lustre for a whole generation, and when, after that long period, it begins to lose its silver coating, it can be re-silvered and made as good as ever. But the price of this article was two hundred dollars, — more than five times the cost of the leaden trash, and a fourth of the price of the solid salver. Nevertheless, plated ware of this quality is the only kind which it is good economy to buy. There are few more extravagant purchases we can make in housekeeping than lead and brass ware, covered with a film of silver so thin that one ounce of the precious metal can actually be spread over two acres of it.

One fact can easily be borne in mind: good serviceable plated articles cost, and must cost, from one fourth to one third as much as similar articles of solid silver. Anything of a much lower standard than this is trash and vulgarity.

For our part, we prefer good plated ware to solid plate. In plated ware we can now have all the beauty of form, all the brilliancy of surface, all the durability and utility of solid silver, without its excessive costliness, without appearing to be guilty of ostentation, without putting our neighbors to shame, and without offering a perpetual temptation to burglars.

IT

T would seem to be folly for any one to maintain that grass is not green, that sugar is not sweet, that the rose has no odor and the trumpet no tone. A man would seem to be out of his senses deliberately to doubt what the world thinks to be simple truths. Yet this paper will deliberately question these truths. It will endeavor to demonstrate that the greenness, the sweetness, the fragrance, the music, are not inherent qualities of the objects themselves, but are cerebral sensations, whose existence is limited to the senses of organized beings.

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Is grass green? First let us inquire what green is, what color is. Light is now understood to be an undulation of the interstellar ether, that inconceivably rare, elastic expanse of matter which occupies all space, an undulation communicated by the incandescent envelope of suns. It moves with such wondrous rapidity as to traverse hundreds of thousands of miles in a second. Such is the generally received explanation of the phenomenon of light; but there is much yet to be explained for which this simple undulation of matter seems to be an insufficient cause. These waves of motion have different lengths and rates of velocity; but the union of them all gives to the human eye the impression of white light. When a prism intercepts their flow, it, so to speak, assorts these differing waves; and, being separated, they then impress the eye with the color of the spectrum, the retina being differently affected by the differing velocities with which it is touched by the ethereal waves. Color, then, is the sensation of the brain, responsive to the touch of the motion of ether; and the brain is only thus affected when these waves are thrown back from some object to the eye. The multiplicity of tints and hues are reflections from the objects which ap

pear to possess them as structural characters. Some of the waves pass into the objects and through them, others are arrested by them and absorbed, others rebound from them like a ball from a wall; and these last, breaking upon the optic nerve, give to it certain sensations which we designate as colors. A wave of a certain velocity and length gives us a certain sensation which we call blue; another awakens the sensation we call yellow. The two series of waves, mingling, produce a new sensation which we call green. The necessity of reflection for the production of these sensations is evident. The mingled waves have no color in their incident flow; but, striking some object, these waves become separated, some being absorbed, and the reflected ones produce the peculiar sensation we call color.

We know that these varying conditions of light which affect us as color have an absolute being. The photographer carries on his nice operations behind a yellow screen undisturbed, when the substitution of a pink one would at once allow of the chemical action of the other rays of light on his plate, to the destruction of his image. Still, the pink and the yellow, as colors, are brain sensations. We feel them with our eyes, and the feeling they awaken we call color. The optic nerve receives the undulations of ether thrown back from grass, and the peculiar sensation thus awakened by their touch is called green. The color is not a part

of the grass, not a quantitative constituent, like its carbon or silex. The grass has no color, because color is something existent in the eye of the beholder, not in the object awakening that something by its peculiar mode of reflecting light. A looking-glass does not possess, as a constituent part, the image of a human face; but that face, when put before it, appears to