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WELL'S PROCESS FOR COPPER-PLATING IRON.

This process yields a coating of copper of great brightness and strong cohesion. The object, whether of cast or wrought iron, is freed from rust by immersion for from five to ten minutes in dilute muriatic acid (2 in 100 water) and subsequent scrubbing for a quarter hour with a wire brush and sand, then washing in water until all traces of acid are removed. It is then covered with zinc-wire in spiral turns of about six inches from each other, which also serves as a means of suspension. The bath consists of a solution of caustic soda (8 p. c.) of which 11 quarts are mixed with 50 ounces of Rochelle salts and 12 of blue vitriol, making a liquid of a density equal to 19° Beaumé. It retains its activity as long as the copper is kept replaced, and deposition from it proceeds with great regularity. The material of the vessel is best when made of wood, lined with gutta percha and covered with a wooden lid.

When the coating is of sufficient thickness, the object is removed from the bath, first washed with water slightly acidified with sulphuric acid, and then with pure water until the disappearance of all traces of acid; after this it passes into a drying room heated to 132° F. The bronzing, when required, is obtained by a bath of sulphide of sodium, or by means of the same bath as above, somewhat modified, that is, by increasing the proportion of copper to a threefold, in which case the bath no longer deposits copper, but, to all appearances, bronze.

By reducing the points of contact between the iron and wire, though retaining the spiral turns at uniform distances, the deposit gradually assumes a number of colors in the following series, viz.: orange, silver-white, pale yellow, golden yellow, carmine, green, brown, and dark bronze.

As soon as the desired color is attained, the object is washed in warm water, and again dried at 132° F. Between each subsequent change of color is an interval of about five minutes. The reaction is more decided when the alkaline reaction of the bath is stronger.

For in-door work or ornaments the time of immersion may vary from 3 to 72 hours; for out-door objects a much longer

time would be necessary, as many as three to four weeks in some cases. To avoid the tediousness of this operation, the immersion in the alkaline bath is only continued for 12 to 18 hours, but after washing in warm water the coated objects are then placed for 12 or 24 hours in an ordinary solution of blue vitriol, which will increase the deposit quite as uniformly, but much more rapidly. In this manner a coating up to one-fifth millimetre in depth may be formed, which is sufficient for out-door work, and even exposure to water.-Kuhnheim, Druggists' Circular, Aag., 1868, from Dingler's Journal, vol. 188, p. 286.

A NEW METHOD FOR GILDING COPPER WIRE

Has been invented by Mr. Hélouis (36 rue Meslay, Paris) by which the blackening so common with ordinary gilding is prevented. It is partly the same plan as that by which platinum or gold-wire of extreme tenuity has been made, i. e., by enclosing these metals within a cylinder of silver or copper, and draw. ing them out together to a fine degree of fineness, when on treatment of the wire with dilute nitric acid, the outer coating is dissolved, leaving a continuous thread of the metal not affected by the acid. In the present case, however, the purpose is to coat the copper-wire with a thin film of platinum, upon which gold may then be deposited without danger of its subsequent blackening, as generally happens when deposited upon copper or even silver, and the object is accomplished by enclosing the cylinder of copper in a heated ring of platinum, which latter, on cooling, contracts and firmly attaches itself to the inner cone; then the drawing-out process proceeds as usual, the resulting copper-wire being coated uniformly with a thin layer of platinum, upon which the gold may be readily and permanently deposited. This process is also more profitable, because the scraps, etc., of wire, which accumulate in working it, are valuable enough to be collected for the purpose of recovering the precious metals. Druggists' Circular, Aug., 1868, from Dingler's Journal, June, 1868.

ON THE GATHERING AND CURING OF CARRAGEEN IN

MASSACHUSETTS.

BY G. HUBERT BATES, Scituate, Mass.

Sub-order: Rhodospermeæ, family Spongiocarpeæ.-Harvey. The generic name, Chondrus, is characteristic of the substance of the frond, being derived from the Greek word signifying cartilage.

Habitat: Rocks in the sea. Perennial; spring. Root: a disk throwing tufts of many fronds, which are from two to twelve inches high, very narrow and subcylindrical at base, but immediately becoming flat, generally dilating from the base till it becomes three or four lines wide, and then dividing repeatedly and dichotomously (by pairs), each division spreading, becoming narrower than the preceding one, and taking place at shorter intervals. The summits are bifid, the segments varying greatly in length, rounded or acute, straight or curved, and often twisted in such a manner as to give the curled appearance denoted by the specific name, crispus. "Fructification roundish or roundishoval, sub-hemispherical capsules imbedded in the disk of the frond, prominent on one side and producing a concavity on the other, containing a mass of minute, roundish, red seeds." Its color is a deep purple-brown, often tinged with purplish red, paler at the summit, and becoming greenish and at length yellowish-white, as the season advances.

This is the proteus of marine algæ. The varieties are innumerable, and pass into one another so insensibly that it is almost impossible to define them. There is great range in regard to the width of the frond. Whenever the plant grows more or less exposed to fresh water, a still greater change is wrought in its appearance. The main divisions are much broader, fewer, and exceedingly irregular, while the margin and extremity are beset with such a vast number of small segments that the whole suggests the idea of monstrosity. In such specimens the frond, when held between the eye and the light, is thinner, more transparent, and frequently mottled with green. It occasionally happens that the margin is somewhat raised, so as to render the frond slightly channelled, but seldom so much as to allow of its being

mistaken for C. mammilosus. The pink seeds are very conspicuous when held between the eye and light. When fully ripe, the capsules fall away entirely, and leave the frond full of holes. Greeville concludes his admirable description-parts of which are included in the above-by remarking that "it is difficult, in words, to convey any idea of the variableness of this species."

The varied uses of carrageen in manufactures make it an article of considerable importance; and the present high prices of glue and isinglass, for which it is an excellent substitute, have created a demand for it heretofore unknown. Up to about the year 1848 all the carrageen consumed in this country was imported from Ireland, which gave it the popular name of Irish moss. It was collected on the southern and western shores of that island, and was converted into size for house painters, and also esteemed for medicinal and culinary purposes. That imported to America was used in making custards and blanc-mange, and sometimes sold as high as seventy-five cents per pound, retail. In 1849 several parties commenced making a business of gathering and curing Chondrus crispus at Scituate, Plymouth county, Massachusetts, and produced the first considerable quantity of the domestic article ever sold in Boston. This is still the only point in the States where any noticeable amount is collected, the business having lately been largely increased, until the annual crop is not far from 500,000 pounds-equal to about 6,000 barrels.

Its range. Some sea-weeds are cosmopolitan, and are equally abundant in all latitudes; but generally algæ are more or less local in their distribution, and different marine floras are found in the different parts of the ocean. The degree of exposure to light, and the greater or less motion of the sea, have an important effect. The green algæ occur either in the shallower parts of the sea or in fresh water; the olive color is characteristic of those sea-weeds that abound between the tide-marks; while the red-colored species grow in the deeper and darker parts of the

ocean.

The sub-order Rhodospermeæ, in which Harvey classes the Chondrus crispus, seem to flourish in the temperate zone, while Chlorospermeæ increase as we pass northward, and Melanosper

meæ towards the tropics. But while Chondrus crispus appears, under certain conditions, to abound in the temperate zone, it is generally incrusted with various minute mollusca, that causes its rejection by the dealers. The rocks on the shores of Scituate, in the main, undoubtedly produce the best article yet discovered in this country. But there are ledges here, where the muscle attaches to the plant, that are wholly abandoned by the mossers. Indeed, the range of the clean-growing Chondrus seems to be very limited.

It has been remarked by those who have visited Cape Ann and the eastern shore for the purpose of testing the quality of the moss growing there, that the product of those parts is of a coarse and limy character. Perhaps, however, this moss, in some instances, may be susceptible of improvement. The old plant should first be entirely removed, which would be immediately succeeded by a new growth; and if this exhibits a marked superiority over the old plants much may be expected of the ledge, for each successive "pull" will produce an improvement in the moss. That the abundant moss growing to the eastward has not been fairly subjected to this test, and the improved article brought into market, indicates either a want of knowledge of the necessary process of improving, or the absence of those whose habits would naturally lead them to engage in the business; or it may be that the plant in that quarter is not susceptible of any improvement, as the report goes.

As regards perpendicular direction, Forbes remarks that one great marine belt or zone lies between high and low-water marks, and varies in species according to the kind of coast, but exhibits similar phenomena throughout the northern hemisphere. This is denominated the littoral zone, and necessarily varies according to the rise and fall of the tides. If I am right in my identification, the Fucus canaliculatus forms the upper sub-region of this zone, followed by a broad belt of F. nodosus and, perhaps, F. versiculosus and F. serratus. This is succeeded by a narrow belt of Chondrus crispus, interspersed with Rhodomenia palmata and Laminaria saccharina, which is exposed only at low ebbs. The Chondrus crispus, however, extends some distance below lowwater mark in to the laminarian zone, its fronds increasing in

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