able character of authenticity. Those sent by Mr. Rutherford Alcock to the Musée Céramique de Sévres, appear to be a repetition of the collection exhibited last year at the Crystal Palace.

In Europe, and especially at Sévres, the coloring metallic oxides are mixed with a flux, the nature of which varies according to that of the color. The most usual is the gray flux (fondant aux gris), which serves for gray, red, blue and yellow, and is formed by melting together

The colors are generally obtained by mixing together 3 parts of flux with 1 part of the metallic oxide, so that the composition may generally be expressed as follows:

Sometimes the oxide and flux are melted together, or calcined before being employed; sometimes they are simply mixed together. If the color be produced by a combination of the oxide with the flux, they must be melted together before use, in order that the color may possess the proper tone. If, on the other hand, the color be proper to the oxide, it need only be mixed with the flux, and must not be melted with it before use, as this double fusion frequently changes the colors. All the colors must melt at the same time, and present, after baking, a sufficiently uniform gloss.

These conditions are not fulfiled by the Chinese colors. Some of them are brilliant, well vitrified, and often laid on so thickly that they project from the surface. This is the case with the blues, greens, and yellows, and with the rose color obtained from gold. Others, such as the ironreds and the blacks, are almost always less thickly laid on, less perfectly vitrified, and generally dull and muddy.

The Chinese paintings are always distinguished from ours by a very distinct character,-the figures and other objects are not properly printed but outlined with a black or red line; the tints are never lowered; the colors are laid on uniformly, and the painter then goes over this ground, either with the same or another color, so as to produce a motley work; but the mixture of the colors on the palette, which constitutes the greatest resource of our painters, appears not to be employed by the Chinese. The appearance of their paintings, when closely examined, reminds one of the mosaic church windows, which were fabricated with so much art in the thirteenth century, and in which the entire design, and all the forms of the figures and accessories, were produced by red or brown lines drawn upon fragments of white or colored glass.

From the thickness with which the Chinese lay on their colors, and their slight intensity, we may arrive at the conclusion, that these colors contain far smaller quantities of metallic oxides than those employed in Europe. The colors are rather enamels.

The names applied to samples investigated by the authors were attached to them in Chinese characters, and have been translated by M. Stanislas Julien.

VOL. XXV.-THIRD SERIES.-No. 6.-JUNE, 1853.

35

The subtances examined included some primary substances employed in the fabrication of the colors. As to the colors, some, not having received any mechanical preparation, are in larger or smaller fragments, and are designated by the generic term Seng; the others are pulverized, and completely prepared for painting; these are included under the generic name Si.

1. Crude Substances and Isolated Oxides.

Sy-chy-mo (fine stone powder).-This is a siliceous, amorphous, grayish powder, becoming white on burning. Some minute spangles of mica are visible in it with the lens. It is infusible before the blowpipe, and presents all the properties of the siliceous sands employed in the fabrication of glass. Analysis gave

The Sy-chy-mo is probably the substance employed by the Chinese in the fabrication of their colored enamels. They use it also, according to Father Ly, to harden colors which are found too fusible.

Yuen-feng (lead-meal).-Four different samples of this material were ascertained, on an analysis, to consist of white lead. This white lead is completely soluble in dilute nitric acid, with the exception of a trace of silica; it is free from oxide of copper and acetate of lead.

Fan-kong is a light red powder, which stains the fingers, is soluble in boiling muriatic and sulphuric acids, and not readily attacked by nitric acid. The Chinese use this substance mixed with some white lead, or silicate of oxide of lead, for the production of red. It appears that the Chinese prepare this red color by the calcination of some natural deposit of yellow ochre, although this cannot be determined with certainty, as Father d'Entrecolles has already informed us that the Chinese are acquainted with copperas (which they call Tsao-fan), and also with the residue of its distillation. The authors have examined two different samples, one, a, from the collection of the Ecole des Mines, the other, b, from that of the Musée Céramique. Their composition is

Thsing-hoa-liao--The Ecole des Mines possesses eight different specimens, three of first, two of second, and three of third quality. All the samples consist of the same material in various states of preparation. One of the three specimens of first quality presents the material in its rough state, as first taken from the mine; the others are in various states of purification. The collecton of the Musée Céramique only possesses one substance similar to the thsing-hoa-liao; it was sent by Father Ly under the name of ching-lan, which he translates deep blue. The collection sent by Mr. Rutherford Alcock contains several bulky specimens of this mineral,

which is a peculiar kind of oxide of cobalt. It forms irregular fragments, containing hollow spaces, of a deep brown color with a greenish tinge, and furnishes a brown powder which stains the fingers. On being heated, it evolves water, and after long continued calcination acquires more of a greenish hue. At a red heat it suffers a loss of 20 per cent. in weight. It contains oxides of manganese and cobalt, but these two oxides do not form the whole of its mass. Muriatic acid leaves a residue of silicate of alumina. During solution in muriatic acid, chlorine is evolved, and the solution contains the metals. Analysis gave—

The powder of this mineral melts with borax before the blowpipe into a rose colored globule, which however has a tinge of blue from the oxide of cobalt. Laid with the pencil upon a piece of burnt Sévres porcelain, then glazed and exposed to the strong fire, it furnished a blue tint in the thinner parts, becoming grayish in the stronger shades. The Chinese employ this substance for the production of blue pictures under the glazing; and if it be rich enough in oxide of cobalt, also in the preparation of the blue muffle colors; and lastly, in the production of black. All the samples come from the province Yun-nan, where the ore is dug from the summit of a mountain. Before use, it is roasted and pounded. The same statement has already been made by Father d'Entrecolles.

(To be Continued.

AMERICAN PATENTS.

List of American Patents which issued from April 12th, to May 10th, 1853, (inclusive,) with Exemplifications by CHARLES M. KELLER, late Chief Examiner of Patents in the U. S. Patent Office.

APRIL 12.

14. For an Improvement in Harrows; William Berlin, Berryville, Virginia.

Claim.-"Having fully described the advantages of my improved harrow, what I claim is, the constructing a double frame work of iron bars or straps of metal, and the arranging and combining the two together by graduating bolts or adjustable screws and taps, by which means, or contrivance, the lower frame can be elevated or depressed, and the teeth or tines lengthened or shortened in their drag or dip."

15. For an Improvement in Spring Mattresses; Edwin L. Bushnell, Poughkeepsie, New York.

Claim. "What I claim as my invention is, the mode or principle of securing the springs, by attaching the free extremity of each spring to the terminal coil of the adjacent spring, so that they mutually support each other, without the use of any inflexible frame of wood or other material, at the same time that in rolling or folding up the mattress, the outside ends of the springs expand or open, while the inside ends contract or close, and by which means any article, so constructed, will admit of being rolled or folded upon itself, or compressed, substantially as described."

16. For an Improvement in Smut Machines; H. L. Fulton, Chicago, Illinois.

"The nature of my invention consists, 1st, in the employment of a circular collar or prismatic shaped concentrator being placed between each pair of revolving scouring plates, and inclining toward the centre of the machine, for the purpose of throwing the grain, as it is, by centrifugal force and the fans, &c., thrown against the inner periphery of the outer casing or concave, back towards the centre of the machine upon the inclined fans and second scouring plate; and thus the grain is prevented from passing down between the inner periphery of the case, and the outer periphery of the revolving dished shaped plates, before it is perfectly cleaned. 2d, The employment of the revolving dished shaped scouring plates, in combination with the prismatic ring on the case, for the purpose of concentrating and directing the grain from one beater to the other."

Claim. "Having thus fully described the nature of my invention, I would state that I am aware that a flat plate, on the side of the concave, has been used; this, therefore, I do not claim; but what I do claim as my invention is, the circular prismatic shaped brace and concentrator arranged between each pair of revolving scouring plates, and secured fast to the inner periphery of the case, for the purpose of concentrating the grain, and throwing it up the second scouring plate, and thereby preventing its escape, before it is effectually cleaned, from the first scouring plate, directly to the discharge passage, substantially as described. I also claim, in combination with the revolving dish shaped plates or beaters, such as herein described, the prismatic ring, for the purpose of concentrating and directing the grain from one beater to the other, substantially as described."

17. For an Improvement in Match Splint Machines; Reuben F. Gustine, Chicago, Ill. Claim.—“What I claim as my invention is, the combination of the reciprocating knife, with a convex or protuberant rest, and feeding and holding mechanism, and the pressure roller, or any equivalent thereof, for the purpose substantially as described."

18. For an Improved Coin Safe and Detector; Jacob J. Hatcher, District of Spring Garden, Pennsylvania.

Claim. "Having fully described the nature of my invention, what I claim therein as new is, a coin safe, or receptacle for coin, consisting of the arrangement of the outer case and spring with its pad, for holding the coin up against the top of the case, and a slide with its projection, or their equivalents, for forcing out the coin through the slot provided for the purpose, substantially as described.”

19. For an Improvement in Manufacturing Rosin Oil; Samuel W. Hawes, Boston, Massachusetts.

"My improvements consist in the arrangement of pipes in such a manner as to discharge the oil, during the process of distillation, separate from the spirits, acid, and naphtha, while at the same time the three last ingredients are discharged into a separate vessel, apart from the oil; this leaves the oil free from smell, and of much better color and quality than when manufactured in the ways now in use, when all the different ingredients are discharged through one and the same worm. Another important improvement is the discharging the still, after the oil has all been distilled, and recharging it, without cooling down and opening it, by which much time and expense is saved.”

Claim. "Having thus described my improvements in making rosin oil, I wish it to be understood, that I do not claim the form or kind of apparatus set forth, irrespective of its use, or particular application; my claims being founded upon the invention or discovery of improvements in the process of making rosin oil, by means of said apparatus, or any other the same or equivalent in principle. Therefore, I claim, first, in the process of making rosin oil, the charging and discharging the still, by means substantially the same in principle or mode of operation as those set forth, whereby I save the necessity of unluting, and prevent the incrustation of the still. Second, I claim in the process of making rosin oil, the separation of the oil from the mere volatile products, at different and distinct points remote from the still, instead of discharging them altogether, as heretofore done, substantially in the manner set forth, that is to say, by means of the series of recurved pipes, in combination with the series of condensers attached thereto, as set forth."

20. For an Improvement in Shingle Machines; Simon Ingersoll, City of New York.

Claim.-"Having described the nature and operation of my invention, what I claim as new is, the spring clipper, operated as described, in combination with the riving knife, for the purpose of insuring the complete separation of the shingle from the block, and at the same time throwing it on the lower bed, in position to be carried to the dressing knives by the next advance of the driver, in the manner substantially set forth."

21. For an Improvement in Hot Air Registers; Edward A. Tuttle, Williamsburgh, New York.

"The nature of my invention consists in constructing the leaves of a ventilator and register with projections on their surfaces, to form an ornamental fret work between the leaves or slats, when they are turned with their edges uppermost, or partially so, for the purpose of dispensing entirely with the open ornamental top plate, which is now employed on air registers and ventilators, to hide the rough brick work or back ground behind the ventilator and register."

Claim. "What I claim as new is, constructing the leaves (of a register or ventilator) with projections on their surfaces, to form an ornamental open or fret work between the leaves, when they are turned with their edges uppermost, or partially so, for the purpose of dispensing with the separate front or top plate, of ornamental open work, now employed on registers and ventilators."

22. For an Improvement in Feeding Clamps for Sewing Machines; William H. Johnson, Granville, Massachusetts.

Claim. "What I claim as my invention is, the use of a hollow rotary clamp, as described, for holding and feeding cloth, and other materials to be sewed, substantially as specified."

23. For an Improvement in Mercury Baths for Daguerreotyping; Benjamin F. Upton, Bath, Maine.

Claim. "What I claim is, the improvement of combining with the mercury bath and the lamp for heating it, the sliding tube and the lever, (or their mechanical equivalents,) as described, so that by the expansion of the bath, the lever may be moved, so as to elevate the slide tube on the wick, and thereby decrease the flame of the lamp, and the heat thereof, or caused so to act as to maintain or nearly maintain equality of evaporation, in the manner and for the purpose as specified."

24. For an Improvement in Washing Machines; Charles F. Wilgus, West Troy, New

York.

Claim.-"Having fully described the nature and operation of my invention, what I claim as new is, the employment of the revolving feeding net cylinder, in combination with the two sets or circles of rollers, one set of said rollers being allowed to yield, when the sack of clothes or other article is drawn round the net cylinder, and between the said sets of rollers, and made to spring back, by means of springs, which are connected to the rollers, in the manner substantially as shown; the whole being constructed, arranged, and operating in the manner described, and for the purpose of washing clothes, and fulling and flocking cloths, as set forth."

25. For an Improvement in Manufacturing Gutta Percha and India Rubber; Chas. Goodyear and Robert Haering, Assignors to Charles Goodyear, New Haven, Connecticut; patented in England, March 4, 1851.

Claim. "Having fully described the nature of our invention, what we claim is, the art or method of manufacturing articles, composed in part of caoutchouc, or other gums susceptible of vulcanization, by heating or vulcanizing the same, when surrounded with and pressed upon externally or internally by or moulded in pulverized soap stone, sand, plaster, or other similar granular, pulverized or porous matter, or in moulds of plaster, or other porous substance, substantially as herein described."

26. For an Improvement in Machinery for Shaving the Heads of Screw Blanks; Cullen Whipple, Assignor to the New England Screw Company, Providence, Rhode Island; patented in England, November 30, 1852.

Ciuim.-"I am aware, that in machines for shaving the heads of screw blanks, the shaving cutter, whether moving on a slide or a rocker, has been moved towards and from the blank, obliquely to the axis of the blank, and therefore, I do not claim broadly the moving of such cutter obliquely; but what I do claim as my invention is, the method of shaving the heads of screw blanks, by causing the cutter to approach the blank obliquely, and in or nearly in line with the under side of the head, whereby the use of a rest, to support the blank against the pressure of the cutter, is dispensed with, substantially as herein set forth."

APRIL 19.

27. For Improvements in the Feed Motion of Willowers; Francis A. Calvert, Lowell, Massachusetts.

Claim.-"Having described my improved willower, what I claim as my invention is,