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principle of generic classification is organic. I assume that every organic variation is a sign of genus; that nothing but organic variation is a sign of genus; that we are too ignorant at present of the real nature and use of most organs to decide on their relative value and to reject some because they seem comparatively uninfluential on the habits and economy of the animal endowed with them; that the organ is always the datum; its use always the desideratum, and that all organs ought to be prominently set forth until their structures, uses and relative importance be decided on; that all three sorts of teeth are organs, and all therefore are properly introduced to mark genera and' even higher groups; that there is not that entire uniformity of dentition among the Ruminants which has been so long asserted; and, lastly, that the special form of the horns in the Cirvidæ, though not strictly an organic mark, may yet be wisely used at present to help the indication of genera, because it is a very palpable sign, and one besides usually harmonising with, and indicative of other and organic modifications yet partially or wholly understood.*
Notice on the Ferruginous Spherules imbedded in Sandstone from Lullutpore, in Bundelcund, by Dr. G. G. SPILSBURY.-By H. PIDDINGTON, Curator Museum Economic Geology.
We have received from Dr. Spilsbury an additional supply of the curious little Ferruginous Spherules described in my report of September 1846, from their resemblance in miniature to the spherical volcanic Bombs figured by Mr. Darwin as being possibly volcanic grape-shot, and since that time I have observed that some being sent to the Agricultural Society, Dr. McClelland thought they might be fossil fruits. I have seen these and find them externally the same as ours, and I have therefore submitted ours to a farther examination, of which the result is―
That they are infusible before the blowpipe; that they are not magnetic, but when exposed to the reducing flame of the blowpipe they become so. That when dissected by long immersion in muriatic acid they leave nothing but a residuum of coarse white granular silex and
Mr. Hodgson's correction of an oversight in the description of Genus Axis, page 691, reached us after the sheet had been printed off. For "canines in males only," read "" I canines in both sexes."-EDS.
a finer one in a gray impalpable powder, which being examined before the blowpipe is silica with oxide of Iron.
There is no trace of any thing like organic arrangement, such as cells, &c. which are rarely completely obliterated in fossil fruits, how complete soever the mineralisation of the substance of the fruit may be.
The strongest proof however to my mind that they are not fossil fruits, but originally ferruginous spherules, whether formed by volcanic action (or by that which produces the pisolitic iron ores?) arises from the matrix in some of the specimens being almost wholly destitute of iron! and the spherule having evidently given iron to it, round its place, in which when detached it leaves a coating of peroxide of iron which stains the sandstone. Now if the spherule had been originally a fruit, it must have obtained its iron from the sandstone itself or from filtration through it, which would have stained it, for we know of no colourless solution of iron like those of silex and lime, which may pass through a rock and be deposited in bodies for which they have an affinity without leaving coloured traces of their passage.
One which I fractured contained a nucleus, excentrically situated, of coarse sand, as if it had been inclosed in a globule of molten iron. This spherule weighed 33 grains and gave by muriatic acid approximatively as follows:
Of coarse silica, ....
Fine impalpable powder of silica with some iron,..
I am therefore still inclined to think these spherules inorganic, and that they have been suddenly deposited in their present position as ferruginous globules, but by what agency we cannot say. The amount of sand in them would almost entitle them to be called ferruginous sandstones.
Mr. Darwin, in his recent work on South America, p. 123, describes some ferruginous volcanic concretions, which are however fusible, as from two inches to two feet in diameter; their insides consisting of a fine scarcely adherent volcanic sand or of an argillaceous tuff. He quotes also D'Aubuisson (to whose work I have not the opportunity of referring) as adverting to the tendency of iron to form hollow concre
tions or shells containing incoherent matter. Our spherulites are evidently yet a problem for resolution, and it is only by attention to the mineralogical conditions of it that we can hope to see its geological bearings properly estimated.
Notice of the Deo Monnees,* or sacred beads of Assam, by the same.
Major Jenkins sends me in a letter a string of six of these singular objects, of which he says:
"I shall be obliged if you can tell me what these beads are, and if you know where any similar are to be had, and whether they are artificial or natural? I suppose the latter are jaspers?"
"You may have seen such and blue and white beads made into necklaces by the Faqueers, the blue and these are in very great demand with all our hill tribes, and could I obtain a few strings of sizes they would be very useful to give as occasional presents to chiefs whom we may seek to attach to our government. Why these beads are considered so valuable amongst these tribes I only account for by supposing they are very scarce, could they not be easily imitated ?"
And Captain Smith writing to him says:
"I send you some of the Deo Monnees so prized by the Singphos and without a string of them, a wife is not to be had. I send small ones, as I should have to pay 5 Rs. for a large sized one; those similar in grain to the Ash wood and irregularly bored are most prized, they should be of both the colors I send; they are valued most because they are supposed to be the real Deo Monnee, and are said to be found ready bored. Those that are particularly smooth outside, and regularly bored are not so valued, as they are thought to be the work of man's hands, whereas the others are by the gods themselves."
These singular objects of veneration (the small-sized ones as sent to us) are small flat circular disks, about from one to 11⁄2 eighth of an inch thick and from one to two eighths in diameter, with holes in the middle or towards it. The colors are from a dirty greenish yellow to a bright sealing wax red; some are yellowish and marbled with the red colour in veins like Jaspers, but the red ones are not marbled with yellow. These * Deo Monnee, Jewel of the gods.
disks appear at first sight like sections of the jasperized stems of gramineous plants, or small pithy wood, and at the edges some of them (the yellow more than the red) appear marked with strice exactly like part of a small petrified twig. When polished however no traces of vessels can be discerned on the transverse section of either the green or red ones by a magnifier.
Selecting one which was a fair medium between the yellow and the red, I submitted it to the following tests. entire weight was not more than 1 grain.
Premising however that its
It is excessively brittle, the fracture may be called splintery-conchoidal, as well as one can distinguish in such minute specimens, and it is the most splintery substance I am acquainted with, the slightest touches of the pestle making it fly as if from an explosion, so that it must be powdered in a covered or a steel mortar. The fractured surface is that of a red enamel or bright sealing wax. The powder resembles brick-dust. The hardness is 5-6, or between Apatite and Adularia. It scratches Fluor readily, and does not yield to the knife.
It does not adhere to the tongue or show any effervescence with acids. Its smell, if any thing with such small specimens, is metallic when breathed upon. It is not magnetic.
Before the blowpipe in the forceps and on charcoal it fuses immediately to a dark steel-coloured brilliant globule, which below is marbled with broad greyish and dirty white veins. This globule is not magnetic and internally has the red fracture of the fresh Deo Monnee.
With borax on Platina wire it fuses entirely to a bright emerald green glass while hot, which becomes of a pale blue on cooling.
With the addition of metallic tin this bead gives a brownish red enamel. The colouring matter of the Deo Monnee therefore is principally protoxide, and perhaps the suboxide of copper, and, as will be subsequently seen some iron.
The powder is not soluble in Muriatic, Sulphuric or Nitric acids. The Sulphuric acid gives it a dull brick or brown-red colour which becomes brighter after several days, the other two acids brighten the powder almost to an orange, though quite colourless.
Boiled in Nitro-Hydrochloric acid a part appeared to dissolve and the vapour had a remarkably disagreeable smell.
The filtered solution gave traces of Iron, and faintly but distinctly of Copper, though not so strong as one would expect from the blowpipe test. The red powder remaining on the filter fused readily with caustic soda in a silver capsule, and when cold was a dirty greenish mass, the whole of which was soluble in Muriatic acid and the solution gave also traces of Iron and Copper.
It was evaporated to dryness and redissolved in pure water, when it left untouched a buff-coloured powder, which by the blowpipe was found to be silica tinged with Iron, the solution gave as before traces of Iron; but was too dilute to show the Copper. I suppose indeed that much of the Copper may have been volatilised, and it is possible that the substance may contain Arsenic.
The above I publish merely as a guide for future investigations when more of the substance can be obtained, such preliminary notes being always of great utility to the working chemist. In reply to Major Jenkins I should say―
That the fusibility and low degree of hardness of the one bead we have experimented upon, while it puts it out of the classes of Jaspers and Pitchstones (of which further we know of none containing copper?) would incline as to believe that it is an enamel, in which the oxides of copper are frequently used as the red colouring matters; and it is not difficult to suppose that the Singphos obtain these, fabricated to imitate Jaspers of these colours, through tribes in intercourse with the Chinese of Yunan. The talent of the Chinese in enamel work of all kinds we well know, and no doubt the beads might be imitated by any person who understood enamelling.
The only natural mineral beads I can find in the bazar are red and white cornelians. Some of blue glass have, I observe, strice on the unground facets so that the circumstance of our Deo Monnees having them does not count as an evidence of their being natural productions.