the mixture of hydrochloric acid and peroxide of manganese, or of sulphuric acid, peroxide of manganese, and chloride of sodium, to remain for twelve hours in contact with the auriferous sand d; and, then, instead of washing-out the solution of gold, I added a small quantity of water, which removed a part of the acting agent, and this was made to percolate several times through the sand; by which method I succeeded in extracting from the sand, within a fraction the whole of the gold. I then repeated the last experiments with natural auriferous quartz, and easily extracted the two ounces of gold per ton which it contained. I therefore propose the following plan for extracting the gold on a commercial scale:The finely-reduced auriferous quartz should be intimately mixed with about one per cent of peroxide of manganese; and if common salt be used this material should be added at the same time as the manganese, in the proportion of three parts of salt to two of manganese. The whole should be then introduced into closed vats, having false bottoms, upon which is laid a quantity of small branches covered with straw, so as to prevent the reduced quartz from filling the holes in the false bottom. Muriatic acid should then be added if manganese alone is used, and diluted sulphuric acid if manganese and salt have been employed; and, after having left the whole in contact for twelve hours, water should be added so as to fill-up the whole space between the false and true bottoms with fluid. This fluid should then be pumped-up and allowed to percolate through the mass; and after this has been done several times, the fluid should be run off into separate vats for extracting the gold and copper that it may contain. To effect this, old iron is placed in it to precipitate the copper; and after this has been removed, the liquor is heated to drive away the excess of free chlorine, and a concentrated solution of sulphate of protoxide of iron, or green copperas, must be added, which, acting on the gold-solution, will precipitate the gold in a metallic form. By this method, both gold and copper are obtained in a marketable condition. If silver is present in the ore, a slight modification in the process will enable the operator to btain this metal also. It is simply necessary to generate the chlorine of the vitriol, manganese, and chloride of sodium process, taking care to use an excess of salt, that is, six parts instead of three, as above directed. The purpose of this chloride of sodium being to hold in solution any chloride of silver that may have been formed by the action of chlorine on the silver-ore, and to extract the metal, the following alteration in the mode of precipitation is

necessary. Blades of copper must be placed in the metallic solutions, to throw down the silver in a metallic form, then blades of iron to throw down the copper, the gold being then extracted as previously directed. I think the advantages of this process are, 1st, cheapness; 2nd, absence of injury to the health of the persons employed; 3rd, that not only is the metallic gold in the ore extracted (as is done by mercury), but it attacks and dissolves all gold which may be present in a combined state, besides enabling the miner also to extract what silver and copper the ore may contain. I cannot, however, conclude without reminding you of what is generally underrated; that is, the heavy expenses which attend the bringing of the ore to the surface of the ground, and crushing and preparing it for being acted upon by mercury or by any other agents.

MISCELLANEOUS.

ILLUSTRATION TO DR. DAWSON'S ARTICLE ON THE GENUS RUSOPHYCUS.

CALLUNA VULGARIS IN NEWFOUNDLAND.-Mr. Murray, late of the Geological Survey of Canada, and now engaged in a survey of Newfoundland, has brought to Montreal specimens of this plant, which were collected by Judge Robinson on the east coast of Newfoundland, near Ferryland (lat. 47°, long. 52° 50′), and which are stated to be from a small patch of the plant not more than three yards square. The locality is in the same part of the island to which the specimens collected by a Mr. Cormack (or MacCormick), and formerly in the collection of the Linnean Society, are referred, (American Journal of Science, vol. xxxxviii, p. 122,) namely the south-east peninsula; and two additional localities in this peninsula are noticed in Cormack's label, namely, the head of St. Mary's Bay and Trepassy Bay or Harbor. It is supposed that the Cormack who collected these specimens is the well-known explorer of the interior of Newfoundland; but we do not find any notice of the plant in his published narrative, although it contains many botanical notes.

De la Pylaie was no doubt the first to collect the plant in Newfoundland, since, though it is not in his herbarium, Prof. Brunet informs us that it is mentioned in his MS. notes.

We now have certain knowledge of localities of heather in Massachusetts, in Cape Breton (see ante, page 378), and in Newfoundland, to which may be added Giesecke's testimony that it occurs in Greenland.

THE GOLD OF NOVA SCOTIA OF PRE-CARBONIFEROUS AGE. -At Corbitt's Mills, about four miles north of Gay's River, Colchester County, Nova Scotia, auriferous clay-slates of the same character as those of the other Gold districts of the Province, are overlaid unconformably by nearly horizontal beds of grey and red conglomerate, grit, and sandstone, of Lower Carboniferous, probably Lower-Coal-measures age. At the mills these last are only a few feet in thickness. They, in turn, are overlaid by a mass of drift, and by beds of stratified sand and clay of variable thickness.

The little brook supplying the water-power to the mills, has out through the Post-tertiary and Carboniferous beds, and in some places has worn for itself a channel in the slates, so that in the numerous excavations on its banks very good sections are exposed.

As to the Carboniferous age of the conglomerate and sandstones there can be no doubt. They cannot be Silurian, for they overlie

uncomformably rocks of this age. They are totally unlike any Devonian rocks occurring in the Province, while they agree perfectly with the Lower Carboniferous conglomerates and sandstones of the Carboniferous basin on the margin of which they lie. They contain a few ill-preserved fossil plants like those found in similar Carboniferous beds. Between the Carboniferous and Drift, the only formation occurring in Nova Scotia is the New-Red-Sandstone, to the rocks of which the beds under consideration bear no resemblance. They cannot be of drift-age, for their fragments form rounded boulders in that deposit. They show no sign of having suffered from metamorphism. The lower part of the beds of conglomerate or grit at their junction with the slates, is richly auriferous, the gold occurring principally in the form of flattened scales, sometimes a quarter of an inch in diameter, disseminated through the rock. I have seen many fragments of the conglomerate, not a cubic inch in size, on the surface of which twenty or thirty scales of gold could be counted with the naked eye. Levels are driven into the banks of the brook, at the junction of the two formations: a foot or more of the lower part of the conglomerated bed is removed and washed in the common miner's cradle and yielding rich returns. It is from this source that the greater part of the gold mined at the locality is obtained.

pan,

A machine is being erected on the spot to crush the conglomerate, in order that the gold may be more thoroughly extracted.

Gold has been washed from the drift overlying the conglomerate. The source whence the gold was derived, was, doubtless, quartzveins in the clay-slates. Only one lead, about a quarter of an inch in thickness, has been discovered beneath the conglomerate. It is richly auriferous, and has a strike of about north and south, and a dip to the eastward of 70°. Non-auriferous quartz-veins are very numerous in the slate-hills of the vicinity. That this lead is older than the Carboniferous strata is plain from its ending abruptly at the junction with the slates.

From the above facts I think there can be no doubt that the gold of Corbitt's Mills is of Pre-Carboniferous origin; and since the gold of that locality was derived from strata precisely similar in character to those of the other gold-regions of Nova Scotia, and which strata are but the re-appearance northward of the gold-bearing rocks of the gold-fields of Renfrew and Oldham, and of the metamorphic band of the Atlantic coast, I think that the PreCarboniferous age of the gold of Nova Scotia is clearly indicated.

It is a very generally accepted theory, propounded by Sir Roderick Murchison, that, while gold is confined to Lower Silurian strata, it did not make its appearance therein until just before the time of the drift. As the gold of Nova Scotia was probably introduced into, or assumed its present form in the quartz-leads, at the time of the metamorphism of the Silurian rocks, which metamorphism was Pre-Carboniferous, I had doubted the correctness of this theory. The occurrence of gold in the Carboniferous rocks of Corbitt's Mills, shows that it is not to be applied to the Province of Nova Scotia.

Halifax, Oct. 27, 1864.

G. FRED. HARTT.

OBITUARY.

PROFESSOR BENJAMIN SILLIMAN.

Our honored associate, Professor Benjamin Silliman, the founder of this Journal (Silliman's Journal), whose name has appeared upon the title-page of every number, from the first until the present, is with us no more. He died at his residence in New Haven, early Thursday morning, November 24, 1864, (the day set apart for a national thanksgiving,) having reached the age of eighty-five years.

It becomes our duty to place on record in these pages, as an inscription to the monument which he has himself erected, an outline of his career and a tribute to his memory. Few men enter life with such promise as he; fewer still sustain themselves so evenly, and die so widely lamented.

Instruction in natural science has been his great work; and in it he was emphatically a man of the times. Beginning when almost nothing was known in this country of the departments to which he was especially devoted, he lived to see them carried forward to a high degree of progress, and their importance everywhere acknowledged. His life, which was one of few marked incidents, was passed in his native State, in connection with Yale College, the institution that early selected him as one of its faculty. Two or three times he was invited to become the president of colleges elsewhere, but New Haven continued his chosen home. Twice he visited Europe, first in 1805-6, in order to qualify himself for