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peroxyd of barium, the nitrate of the protoxyd of manganese being formed in the first case, and in the second, besides this salt, the nitrate of baryta. It is hardly necessary to state, that in bothc ases the -0 of the permanganic acid and the + of the peroxyd of hydrogen or barium are disengaged as 0.

3. An aqueous solution of chromic acid containing some nitric or sulphuric acid and peroxyd of hydrogen are rapidly transformed into the nitrate or sulphate of oxyd of chromium, HO, and inactive oxygen, which is of course disengaged. A solution of chromic acid mixed with some nitric acid and BaO2 gives a similar result, nitrate of baryta and oxyd of chromium being formed, and 0 disengaged.

4. If you add to a mixture of any peroxyd salt of iron and the red ferro-sesquicyanuret of potassium (both substances dissolved in water) some peroxyd of hydrogen, prussian blue will be thrown down and inactive oxygen set free. On introducing into a mixture of nitrate of peroxyd of iron and the ferro-sesquicyanuret of potassium the peroxyd of barium, a similar reaction takes place, prussian blue, nitrate of baryta, &c., being formed, and inactive oxygen eliminated. From these facts it appears that, under certain conditions, even peroxyd of iron and HO? or BaO2 are capable of catalyzing each other into Feo and HO, or BaO and O.

5. Under certain circumstances PbO? or MnO2 are soluble in strong acetic acid; now if you add to such a solution HO? or BaO?, the peroxyds will be reduced to H0 or Bao, and PbO or MnO, inactive oxygen being disengaged.

6. It is a well known fact that the oxyd of silver = Ag(-ė), or the peroxyd of that metal =Ag(-0)?, and the peroxyd of hydrogen =H0+(+0), catalyze each other into metallic silver, water and inactive oxygen. Other ozonids such as Pb0+(-0) or MnO+(-ė), on being brought in contact with H0+(+0), are transformed into Pbo or MnO, HO and O. Now the peroxyd of barium =Ba0+(+o), acts like H0+(+0). If you pour water upon an intimate mixture of Ago, or Agoo and BaO, a lively disengagement of inactive oxygen will ensue, Ago,'AgO2 and Baðs being reduced to metallic silver and baryta. In concluding the first part of my letter, I must not omit to state the general fact, that the oxygen disengaged in all cases of reciprocal catalysis of oxy.compounds, behaves in every respect like inactive oxygen.

There is another set of chemical phenomena, in my opinion closely connected with the polar states of the active oxygen contained in the two opposite classes of peroxyds. It is known that a certain number of oxy-compounds, for instance the peroxyds of manganese, lead, nickel, cobalt, bismuth, silver, and also permanganic, chromic, and vanadic acids, furnish with muriatic acid chlorine, whilst another set, such as the peroxyds of barium, strontium, potassium, &c., are not capable of eliminating chlorine either out of the said acid or any other chlorid. This second class of oxy-compounds produces, however, with muriatic acid, the peroxyd of hydrogen; and it is quite impossible in any way to obtain from the first class of the peroxyds HO", or from the second chlorine.

You are aware that, from reasons of analogy, I do not believe in the doctrine of chlorine, bromine, &c., being simple bodies, but consider those substances as oxy-compounds, analogous to the peroxyds of manganese, lead, &c., in other terms, as “ozonids." Chlorine is therefore to me the peroxyd of murium

=Mu0+(-0,) hydrochloric acid =MuO+HO, and, as already mentioned, the peroxyd of barium =BaO+(+0,) that of hydrogen =H0+(+0,) and the peroxyd of manganese =MnO+ (-0). Proceeding from these suppositions, it is very easy to account for the different way in which the two sets of peroxyds are acted upon by muriatic acid.

From reasons as yet entirely unknown to us, HO can be chemically associated only with +, and with no other modification of oxygen, to constitute what is called the peroxyd of hydrogen; and in a similar way MuO (the hypothetically anhy. drous muriatic acid of older times) is capable of being united only to - to form the so-called chlorine, which I denominate peroxyd of murium. If we cause MuO+HO to react upon BaO+(+0,) MuO unites with Bao, and HO with +0; but if you bring together MuO+HO with Mn part of MuO is associated to MnO, another part to -Ö, water being eliminated, according to the equation 2(MuO, HO)+Mn0+(-8)=MuO, MnO+Mu0, (-ė)+2H0.

As you will easily perceive, from these views it would follow that, under proper circumstances, two opposite peroxyds, on being intimately mixed together and in the right proportion and acted upon by muriatic acid, could yield neither chlorine nor peroxyd of hydrogen, but merely inactive oxygen. If somewhat dilute muriatic acid be poured upon an intimate mixture of five parts of peroxyd of barium and two parts of peroxyd of manganese, the whole will be rapidly transformed into the muriates of baryta and protoxyd of manganese, the active oxygen of both the peroxyds being disengaged in the inactive condition, and

not a trace of free chlorine making its appearance. The same result is obtained from dilute hydrobromic acid.

Another consequence of my hypothesis is this: that an inti. mate and correctly proportioned mixture of two opposite per. oxyds, such as the peroxyd of barium and that of lead, on being acted upon by any oxy-acid, cannot produce the peroxyd of hydrogen; or, to express the same thing in other terms, muriatic acid must act upon the said mixture exactly in the same way as the oxy-acids do; and that is indeed the case. Mixtures of the peroxyds just mentioned and acetic or nitric acids, are readily converted into the acetates or nitrates of baryta and protoxyd of manganese, the active oxygen of both the peroxyds being of course disengaged in the inactive condition.

Before I close my long story I must mention one fact more, which, in my opinion, is certainly a very curious one. If you mix an aqueous and concentrated solution of bromine with a sufficient quantity of peroxyd of hydrogen, what happens ? A very lively disengagement of inactive oxygen takes place, the color and the odor of the bromine solution disappear, the liquid becomes sour, and on adding some aqueous chlorine to it, bromine reappears. From hence we are allowed to conclude, that, on bringing bromine into contact with peroxyd of hydrogen, some so-called hydrobromic acid is produced. The hypothesis at present prevailing cannot account for the formation of that acid otherwise than by admitting that bromine takes up the hydrogen of HO?, eliminating the two equivalents of oxygen united to H. I, of course, take another view of the case; bromine is to me an ozonid like peroxyd of lead, &c., i. e., the peroxyd of bromium =Br0+(-O). Now H0+(+0) and Bro+(-) catalyze each other into HO, Bro, and inactive oxygen, BrO+HO forming hydrobromic acid, or what might more properly be called hydrate of bromiatic acid.

It will be perceived that I am growing more and more hardened in my heretical notions, or, to speak more correctly, in my orthodox views; for it was Davy who acted the part of a heretic in overthrowing the old, venerable, true creed. Indeed the longer I compare the new and old doctrine on the nature of chlorine, &c., with the whole material of chemical facts bearing upon them, the less I am able to conceive how Davy could so lightly and slightly handle the heavy weight of analogies which, in my opinion, speak so very strongly and decisively in favor of Berthollet's views. There is no doubt Sir Humphrey was a man of great genius, and consequently very imaginative; but I am almost inclined to believe that, by a certain wantonness, or by dint of that transcendent faculty of his mind, he was seduced to conjure up a theory intended to be as much out of the way and “invraisemblable" as possible, and serve nevertheless certain

theoretical purposes; and certainly, if he entertained the intention of solving such a problem, he has wonderfully succeeded. But what I still more wonder at is both the sudden and general success which that far-fetched and strained hypothesis met with, and the tenacity with which the whole chemical world has been sticking to it ever since its imaginative author pleased to divulge it: and all this could happen in spite of the fact that the new doctrine, in removing from the field of chemistry a couple of hypothetical bodies, was, for analogy's sake, forced to introduce fictitious compounds, not by dozens only, but by hundreds,—the oxy-sulphion, oxy-nitrion, and the rest of those "nonentia.” But enough of this subject, upon which I am apt to grow warm and even angry. Although the results I have obtained from my recent investigations cannot but induce me to begin another, and, I am afraid, endless series of researches, I shall for the present cut short the matter and indulge for some time in absolute idleness.

Bâsle, June 25th, 1858.

etitious com bodies, atrom the firepite of the pleased to as been

of the existe C, durine large tract

ART. V.- Occurrence of Cobalt and Nickel in Gaston county, North

Carolina ; by HENRY WURTZ, Prof. Chemistry, National

Medical College, Washington. Read in part before the American Association for the Advancement of Science at

Baltimore. April, 1858. * WHILE exploring a large tract of land in Gaston and Lincoln counties, N. C., during the summer of 1857, I found indications of the existence of ores of cobalt and nickel diffused throughout a considerable extent of country.

The region explored comprised a range of rocks composed of alternating strata of talcose and quartzose schists, which crosses the South fork of the Catawba river a little south of the line between Lincoln and Gaston counties, and in the immediate neighborhood of the falls known as the “High Shoals of the Catawba.” The general direction of this range, which forms a well defined metalliferous belt of many miles in longitudinal extent, is about N. 20° E. (varying, however, in places between due N. and N. 35° E.), and at the High Shoals it is three or four miles wide. It is everywhere traversed by “veins” of quartz, carrying pyrites and other sulphids, and showing at the surface the limonite gozzans derived from their oxydation. These “veins" in some places have all varieties of strike and dip, although the most important ones were found most frequently to conform in strike (or very nearly so) with the containing rocks. The dip of these rocks is nearly vertical, usually a little westerly, although notable contortions and local variations of dip were observed in a few places. At the place where this metalliferous belt crosses the river its boundaries appear to be, on the northwest side a thickly bedded granitoid schist, and on the southeast side, forming the barrier over which the water falls at the High Shoals, a massive range of peculiar feldspathic rocks, also thickly bedded in structure, and characterized by having the feldspar crystals, which are numerous and large, all arranged with their longer diameters parallel to the bedded structure, or generally about N. 20° E. On the southwesterly prolongation of this latter rock, wherever it crosses any of the tributaries of the river, a waterfall is found. Crowder's mountain, which towers up about a dozen miles distant in a southwesterly direction, seems to lie on or near this range.

* The proper date of this paper is August, 1857, at which time it was announced to be read at the Montreal meeting of the Association. Accidents beyond the author's control have delayed its appearance until now.

Proceeding to the northeastward from the High Shoals into Lincoln county along this belt of talcose and quartzose schists, many places are encountered where gold has been mined, or washed out from the beds of the small streams, among which may be mentioned the Shuford and Cansler Gold Mines.

Many miles in the distance, but apparently on the same range, is seen the high elevation in which is situated the iron mine known as the “Graham Ore Bank.” Fragments of limonite gozzan and honey-combed quartz are constantly encountered on the surface, sometimes isolated, and sometimes strewed along for considerable distances marking outcrops. In this part of the range, the quartz veins are usually found to contain, wherever they have been opened, more or less galena, blende and chalcopyrite, usually with native gold. In one place rutile was found.

Going southwestwardly from the river we find the rocks presenting similar indications, and in the course of some fifteen miles, we encounter successively the “Long Creek Gold Mines," (from one of which, known as the Asbury Shaft, much gold has been taken); and a number of places where iron ore is or has been mined, known as the “Costner Ore Bank;” the “Alison Ore Bank;” the “Ormond Ore Bank;” the “Ferguson Ore Bank,” and “Briggs' Ore Bank.” A few miles beyond the latter, not far from the same range, lies the well known“ Kings Moun. tain Gold Mine.” So called “greenstone-trap dykes " are occasionally encountered, sometimes running parallel to, and sometimes across, the strata. The beds of the streams frequently contain pebbles of black tourmaline, and the black sand, so common throughout this section of the country, was found to consist here principally of a magnesia tourmaline, easily fusible by the blowpipe. Immense veins, or rather strata, of black tourmaline were also observed in several places, usually veined with milky white quartz. This would form a magnificent material for monumental SECOND SERIES, Vol. XXVII, No. 78.--JAN., 1859.

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