PARAMORPHOSIS OF RUTILE AFTER

ARKANSITE.

BY PROF. GERHARDT VOM RATH. (Poggendorffs Ann. CLVIII, 1876.)

TRANSLATED FOR THE BULLETIN BY PROF. G. A. KOENIG, PH. D.

Some crystals of arkansite from Magnet Cove, which I obtained some time ago through Mr. B. Hürtz. are in many respects very remarkable, and different from those usually obtained at the above locality. They present generally the seemingly dihexahedric form, resulting from an evenlybalanced combination of the prisms with the pyramid, but also forms in which the prism M is largely predominating, as in the accompanying figure. They are further distinguished by a brown color and a curious lustre resembling very much that called "moire metallique" by the French. The faces do not reflect in their corresponding plane, at least not over their entire extent. They show, on the contrary, a spotted appearance of alternating lustrous and dull patches in one position, and at another position a reversion of lustre and dullness on the same spots. As several parts of neighboring faces reflect simultaneously it is demonstrated that the reflecting elements on different faces are in a corresponding position. This phenomenon is similar to the one noticed in some iron meteorites after etching. The satin-like lustre, moire, or false rife is always the result of the formation of new, more or less parallel crystallographic elements in the primary substance. On closer examination, the surface of these arkansites or brookites resolves itself into innumerable small crystals of RUTILE, whilst at the same time the interior is not any more black arkansite, but dark reddish brown rutile. A clear case of paramorphosis of rutile after brookite is thus made out, strengthened by the change in specific gravity. I made several determinations with good sized crystals and found,

Spec. Gr. 4.148-4.212.

agreeing closely with that of rutile (4.18-4.25). Often the rutile crystals are so small that neither their form nor their position can be ascertained with either naked eye or magnifying lens. But they may be recognized by the variation of lustre, which is silky on the prismatic faces and vitreous on those of the pyramid. Most usually, h wever, the rutile crystals are large enough to allow an identification of their form (P. oo P. oo P. oo P. oo oo P) and also their relative position. On one of the specimens before me, (an aggregation of numerous pseudodihexahdric arkansites) the rutile prisms are as long as 5 millimeters, and have evidently attracted the attention of a former observer, as the American label reads: "arkansite with an habit of rutile." lowever, there is not only a covering of the crystals with rutile, but a thorough physical change through their entire mass. From what has been said above, it follows that the rutile crystals possess a parallel position by groups, and not only towards each other, but likewise towards the arkansite, whose form they imitate. There is a ten ency of the small crystals to arrange themselves parallel to certain main planes of the mother crystal. This is not a twinning in the more restricted sense, but merely a kind of similarity in the direction of certain axes or edges. The directing force which the arkansi'o (dwindling in its essence) exercised upon the epigones of rutile is unmistakable. The position of the rutile prisms on the fiens M is mostly vertical in a manner that a face of the prisms of the second order would

coineide with the macropinakoid of the arkanaite. The position is only approximately parallel, and often interrupting. In another position the small crystals are placed across the bracby diagonal edge of the pyramid. It is curious how the moire design assumes irregularly rounded shapes (resembling the lustreless twin-spots in quartz), and again, patches bounded by straight lines, which pass from one face to the other with the same position of the splendent elements.

Thus we have, then, presented to us a new and notable example of the fact that two d morphous modifications of one and the same substance occur in the physical appearance of one body, the ene having left the outlines of its crystallographic form as a memento of its existence, whilst the second dimorphous modification is manifest in the smaller crystals of subsequ nt formation. This paramorphosis is analogous to one known heretofore and described by Dr. Blum, (III. Nachtrag zud. Pseudom. des Mineralreutus, p. 264) that is the t.ansformation of octahedrite (anatose) into rutiles.

The new form that Prof. Vom Rath describes was noticed by me soon after I first visited Magnet Cove, and the figures that illustrate it were engraved about one year ago. The material upon which he made his exceedingly interesting observations passed through my hands. The brookite shown in fig. 7 was obtained by me nearly two years ago, and the actual size is shown. I have specimens of this rare form at from 25c. to $5.00 each.

I desire again to call attention to the exceedingly low rate at which I sell Rutile and Brookite, 25c. each, free from gangue. Shadow or Phantom crystals from Hot Springs, some of which are very beautiful, I can furnish at from 25c. to $2.00.

MELLITE.

This curious compound of an organic acid and alumina I can now furnish in white and honeycolored crystals at 5c. to $1.00. This is the only representative of Division 6 Class 4, Salts of Organic Acids, that is attainable, and as it is found only in Austria it is quite difficult to obtain it. It is therefore a very favorable opportunity to obtain good specimens of an interesting mineral at a low rate.

I have the finest specimens of Partzite ever seen, at rates lower than ever offered before.

I have also just purchased a number of remarkably fine insects in Amber, from the Baltic. Besides flies which are quite common, I have also motes, musquitoes, ants, and, rarest of all, spiders and beetles Good specimens from 50c. to $2.00.

The following minerals and many others heretofore mentioned, in stock in large quantities.

Acadiolite, Achroite, Acmite, Actinolite, Adularia, Ægirite, Agalmatolite, Agate, Agatized Wood, Alabaster, Albertite, Albin, Albite, Algerite, Allanite, Allemontite, Amazon stone, Amber, Amblygonite, Amethyst, Amphibole, Analcite, Anatase, Andalusite, Andesite, Anglesite, Anhydrite, Ankerite, Anorthite, Anthophyllite, Anthophyllite Hyd., Anthracite, Antimony Native, Apatelite, Apatite, Apophyllite, Aquacreptite, Aquamarine, Aragonite, Ardenite, Arfvedsonite, Argentine, Argentite, Arksansite, Arksutite, Arquerite, Arsenic, Arsenopyrite, Asbestu, Asbolan, Asphaltum, Astrophyllite, Atacamite, Atelestite, Augite, Aurichalcite, Autunite, Aventurine Feldspar, Axinite, Azurite.

Baltimorite, Barite, Barnhardtite, Barite, Barytocalcite, Basanite, Beauxite, Beryl, Bismuth, Bismuth Telluric, Bismuthinite. Bitter Spar, Black Jack, Blende, Blende Fire, Blood Stone, Blue John, Bog Iron Ore, Boltonite, Borax, Bornite, Boulangerite, Bournonite, Breislakite, Brookite, Brown Spar, Brucite, Brushite, Bucholzite, Buhrstone, Buratite, Byssolite.

Cacoxenite, Cadmium Blende, Cairngorm Stone, Calamine, Calcareous Spar, Calcareous Tufa, Calcite, Calcozincite, Caledonite, Campylite, Cancrinite, Cannal Coal, Carnelian, Cassiterite, Catlinite, Celestite, Cerargyrite, Cerite, Cerolite, Cerussite, Cervantite, Chabazite, Chalcedony, Chalcocite, Chalcodite, Chalcophanite, Chalcopyrite, Chalk, Chalybite, Chert, Chesterlite, Chessy Copper, Chiastelite, Childrenite, Chilenite, Chlorastrolite, Chlorite, Chloritoid, Chlorophaeite, Chondrodite, Chrome Ochre, Chromic Iron, Chromite, Chrysoberyl, Chrysocolla, Chrysoprase, Chrysotile, Cinnabar, Cinnamon Stone, Citrine, Clay, Clay Iron Stone, Clinochlore, Clintonite, Coal Mineral, Cobalt Bloom, Cobaltite, Cockscomb Pyrites, Coccolite, Colophonite, Columbite, Cookeite, Copalite, Copper, Copper Glance, Copper Gray, Copper Nickel, Copper Red, Copper Vitreous, Copper Pyrites, Corundophilite, Corundum, Cotunnite, Covellite, Crocoite, Cross Stone, Cryolite, Cryptomorphite, Cubanite, Culsageeite, Cuprite, Cuproscheelite, Cyanite.

Damourite, Datolite, Delawarite, Delessite, Dendrites, Derbyshire Spar, Deweylite, Diabantite, Diallage (green), Diaspore, Dimagnetite, Diopside, Dioptase, Dipyre, Disluite, Disthene, Dog-Tooth Spar, Dolomite, Dufrenite, Durangite, Dysluite.

Earthy Cobalt Bloom, Edenite, Elaeolite, Embolite, Emerald, Emerald Nickel, Emery, Emerylite, Enstatite, Epidote, Epsomite, Erubescite, Erythrite, Essonite, Euchroite, Euxenite.

Fahlunite, Feather Ore, Feldspar, Feldspar Green, Feldspar avanturine, Feldspar pink, Feldspar Labrador, Fergusonite, Fibrofferite, Fibrolite, Fire blende, Fire Opal, Flexible Sandstone, Fiint, Flosferri, Fluorite, Fontainbleau Limestone, Forsterite, Fowlerite, Franklinite, Fuchsite.

Gadolinite, Gahnite, Galena, Garnierite, Gearksutite, Genthite, Geode Quartz, Gersdorffite, Geyserite, Gieseckite, Glauconite, Gmelinite, Gueiss, Gold, Goshenite, Göthite, Granite Graphic, Graphic Tellurium. Graphite, Green Earth, Greenockite, Grey Copper, Guano, Gurhofite, Gypsum, Gyrolite.

Haarkies, Hair Nickel, Halite, Hallite, Halloysite, Halotrichite, Harmotome, Hard Coal, Haydenite, Hayesine,

Heavy Spar, Hebronite, Heliotrope, Hematite, Hematite Brown, Hepatic Pyrites, Hercynite, Heulandite, Hexagonite, Hone Stone, Hornblende, Hornblende Labrador, Horn Sil; ver, Horn Stone, Horse flesh Ore, Hortonite, Houghite, Hübnerite, Hyalite, Hyd. Anthophyllite, Hydrotalcite, Hydrotitanite, Hydrozincite, Hypersthene.

Iceland Spar, Idocrase, Ilmenite, Indianfte, Indicolite, Indurated Talc, Iolite, Iridosmine, Iron, Iron Arsenical, Iron Carbonate, Iron Chromic, Iron Magnetic, Iron Meteoric, Iron Micaceous, Iron Oxyd, Iron Specular, Iron Ore Bog, Iron Ore Titanic, Iron Pyrites, Iron Pyrites Magnetic, Iron Spinel, Isopyre, Itacolumite.

Jacksonite, Jacobsite, Jasper, Jefferisite, Jeffersonite, Jenkinsite, Jet, Johannite, Jordanite.

Kammererite, Kerolite, Kolophonite, Kyanite. Labradorite, Lapis Lazuli, Laumontite, Lava, Lavendulan, Lazulite, Lead Black, Lead Carbonate, Lead Molybdate, Lead Phosphate, Lead Sulphate, Lead Vanadate, Leather, Mountain; Leelite, Lepidolite, Leucite, Lievrite, Light Red Silver, Lignite, Lime Carbonate, Limestone, Limonite, Linarite, Linnaeite, Lithia Mica, Lithia Tourmaline, Livingstonite, Lodestone, Loxoclase, Ludwigite, Lumachelle, Lydian-stone.

Macle, Magnesia Borate, Magnesia Hydrate, Magnesite, Magnet Native, Magnetic Pyrites, Magnetite, Malachite, Malachite Blue, Manganese Bog, Manganese Red, Manganite, Marble, Marcasite, Margarite, Margarodite, Marl, Martite, Melaconite, Menaccanite, Mercury, Mercury Sulphide, Mesolite, Metabrushite, Meteoric Iron, Mica, Mica picture, Mica schist, Microcline, Millerite, Mimetite, Mineral coal, Mispickel, Mocha stone, Molybdate of Lead, Molybdenite, Molybdite, Moonstone, Mossottite, Mundic, Muscovite.

Nagyagite, Nailhead Spar, Naphtha, Natrolite, Nephelite, Nertschinskite, Niccolite, Nickel Emerald, Nigrin, Novaculite.

Obsidian, Ochre Molybdic, Ochre Red, Ochre Uranium? Octahedrite, Octahedral Copper Ore, Octahedral Iron Ore, Oligiste Iron, Oligoclase, Olivenite, Olivine, Onyx, Oolite, Opal, Opalized Wood, Orpiment, Orthite, Orthoclase, Orthoclase Green, Orthoclase Pink, Ottrelite, Ozarkite, Ozocerite.

Pachnolite, Paracolumbite, Pargasite, Partzite, Peat, Pectolite, Penninite, Pennite, Peridot, Pericline, Perofskite, Perthite, Petalite, Petrified Wood, Petroleum, Petzite, Pharmacolite, Phillipsite, Phlogopite, Phosphate of Iron, Phosphate of Lead, Phyllite, Pickeringite, Picrolite, Picromerite, Pipestone, Pitchblende, Platinum, Plumbago, Polianite, Polyhalite, Porcelain Jasper, Porphyry, Potstone, Prase, Precious Opal, Prehnite, Priceite, Prochlorite, Protovermiculite, Proustite, Pseudomorphs, Psilomelane, Pyrargyrite, Pyrite, Pyrite arsenical, Pyrite copper, Pyrolusite, Pyromorphite, Pyrope, Pyrophyllite, Pyrorthite Pyrosmalite, Pyrostilpnite, Pyroxene, Pyrrhotite.

Quartz, Quartz Amethystine, Quartz Capped, Quartz Rose, Quartz Smoky, Quicksilver Native.

Realgar, Rhodochrome, Rhodonite, Rhomb spar, Ripidolite, Rock Crystal, Rock Salt, Rogersite, Rose Quartz, .Rubellite, Ruby Spinel, Ruby Oriental, Ruby Silver, Rutile. Sal ammoniac, Salt Common, Salt Epsom, Salt Glaubers, Saltpetre Chili, Samarskite, Sapphire, Sard, Sardonyx, Satin Spar, Scapolite, Scheelite, Schörl, Schorlomite, Selenite, Semiopal, Senarmontite, Serpentine, Shorl, Siderite, Silicified Wood, Sillimanite, Silver, Silver Chloride, Silver Chlorbromide, Silver Glance, Silver Horn, Silver Red or Ruby, Slickensides, Smaltite, Smaragdite, Smithsonite, moky Quartz, Soapstone, Soda Borate, Soda Feldspar, Soda Nitre, Sodalite, Sodium Chloride, Soft Coal, Spathic Iron, Specular Iron, Sphalerite, Sphene, Spinel, Spodumene, Stalactite, Stalagmite, Staurolite, Steatite, Stibiconite, Stibnite, Stilbite, Stolzite, Stream Tin, Strengite, Strontianite, Strontia Sulphate, Succinite, Sulphur Native, Sunstone, Sussexite, Sylvanite, Sylvite, A. Syngenite.

Tabular Spar, Talc, Tellurium, Tellurium Graphic, Tephroite, Tetrahedrite, Thomsenolite, Tile Ore, Tin, Stone; Titanite, Titanic Acid, Titanic Iron, Topaz, Torbanite, Torbernite, Touchstone, Tourmaline, Tourmaline Black, Tourmaline Blue, Tourmaline Brown, Tourmaline Columnar, Tourmaline Fibrous, Tourmaline Green, Tourmaline Lithia, Travertine, Tremolite, Tridymite, Troostite, Tufa Calcareous, Tungstate of Iron, Tungstate of Lime, Tungstate of Lead, Turnerite, Turquois.

Ulexite, Ultramarine, Uraninite, Uranite.

Vanadinite, Vanuxemite, Variscite, Vauquelinite, Verdantique, Vermiculite, Vesuvianite, Vitreous Copper, Vivianite, Volcanic Glass.

Wad, Wapplerite, Warwickite, Wavellite, Wernerite, Willemite, Williamsite, Witherite, Wolframite, Wollastonite, Wood, petrified; Wood-opal, Wood, Agatized; Wulf-nite. Zaratite, Zeolite, Zeunerite, Zinc, Blende, Zinc, Silicate; Zinc, Spinel; Zincite, Zircon.

School Museums.

PROF. DAVID DOYLE, ELORA.

If it be taken for granted that Natural Science is a proper subject for treatment in the Public School course the question immediately presents itself, as to the best method by means of which the necessary information may be imparted to the pupil, simultaneously with the carrying on of the educating process. With reference to this point, scientists and educators, almost without exception, occupy common ground, declaring it their opinion that time devoted merely to the memorizing of bald, text-book technicalities, and viva voce explanations, even when assisted with elaborate diagrams, is little better than frittered away. To this may be added the scarcely less important argument, that the almost inevitable tendency of such a plan is to disgust young people with the study to so great an extent, that very few of them will think of devoting even the smallest portion of their time to the consideration of biological topics, after the business portion of life has been fully entered upon.

What the spirit of the age demands in this, as in some other fields, is close, direct, personal observation and manipulation. For us of to-day, it is not enough that this, that, or the other great man, be he saint, seer or scholar, has said so-and-so. What any or all of them have bequeathed to us for our edification may be all right, but it may not be. The Genius of Inquiry, with his crooked wand, directs the movements of the explorer in every path of knowledge. An individual ipse dixit no longer demands a general amen. The mantle of inspiration has been dropped, and has fallen-nowhere or everywhere.

In no department of knowledge, during recent years, has the influence of persistent, original investigation been more powerfully felt than in Natural Science, and most assuredly, in none other has so much been done to prove that two and two make four, outside the pale of Mathematics. Despite all that has been effected in the way indicated, ten thousand times more remains to be accomplished. "The harvest indeed is ripe, but the, laborers are few."

To teach Natural Science profitably, as already has been hinted, actual specimens are a prime necessity. This, however, need frighten no one. Hundreds of valuable and interesting objects are procurable within a few minutes walk of nearly every school-room-certainly every rural one-in the province, and for the benefit of any who may feel disposed to do even a little towards unlocking Nature's secrets, it is proposed in what follows to throw out a few suggestions to encourage experiment in the formation of School Museums.

The teacher is, of course, supposed to be in possession of some knowledge, in advance of his class-not necessarily very much, but enough to enable him to speak authoritatively. To be in this position, he should have for reference, as well as for study, works bearing on the subjects proposed to be taken up, from as nearly a local point of view as possible. For general perusal books on every department of atural Science may be had anywhere, but to make "talks" interesting to young people, the teacher should be able to speak about things around home.

Having decided upon a study, no difficulty will be found in enlisting the co-operation of the young people in procuring specimens. Let it be distinctly understood that the choice specimens are to be preserved; that if the trustees furnish a few cases, they will become the property of the school, and that every object considered worthy of a place in the cabinet will be labelled with the nanie of the finder. In the event of the teacher supplying case-room the collection of course, should become his property. In country schools, there is no reason why a complete set of plants, illustrative of the local fora, should not be found in every section, and it would be somewhat difficult to suggest anything likely to be more interesting, instructive, or truly useful to the sons and daughters of farmers, than a pretty fair knowledge of botany. Snakes, lizards, frogs, toads, &c., in spirits, should be represented. So far as birds are concerned, it should be borne in mind that a license is required to enable any one to possess, legally, most of our feathered friends, or their nests and eggs. A sharp lookout should be kept for any relics that may turn up, in the shape of stone weapons, or pottery of the aborigines.

In some respects, villages and towns are at a disadvantage compared with rural sections in making collections, but on the whole they are more favorably situated. A short walk from any school-house in Ontario, outside

the cities, will carry one into the country. Not only should the assistance of the pupils in towns be secured, but much from the surrounding farms, that is, on the supposition that specimens are not in demand at the rural schools, and it is not likely this will often be the case. Circulars at a trifling cost may be freely made use of in the neighborhood, stating the kind of objects required, and asking for contributions. Many farmers and their families may by this means be made active coworkers: where the plan has been tried large numbers of desirable specimens have been presented by them. In asking for aid from the surrounding country, it would be well to let it be clearly understood that, should the collection ever assume the ambitious character and importance of a Museum, admission would be free to all, and that visits from country teachers and pupils would be especially encouraged. By-and-by, if the interest is kept up, numerous duplicates of specimens might be collected and then a system of exchange be resorted to with more pretentious establishments, many of which would gladly give away otherwise unprocurable objects, to get possession of what, in the village or town collection at home, may be of little or no value.

In carrying out a scheme of this kind, if gone into at all extensively, some expense must necessarily be entailed, but it is really surprising how much may be done at a trifling cost. With proper management, in the midst of an appreciative community, and with an intelligent Board of Trustees, one hundred dollars per annum will maintain the collection in a flourishing condition, inost of the money going for the supply of cases, payment of freight, postage, and express charges. To any teacher undertaking such an enterprise-for it is nothing short of that-no remuneration, pecuniarily, need be looked for. It must be "a labor of love." Even where the people possess more than average good sense there is a disposition to regard the teacher as quite well enough, if not too well, paid for all he may do. His only reward must be the interest he succeeds in awakening amongst his "disciples." His pleasure must consist in having led them to enquire for themselves-to take nothing for granted which it is possible to prove. He must remain satisfied with having-and he should not be satisfied till he has-led them to exercise their powers of observation, to form opinions for themselves, to apply analysis in investigation, to generalize their disconnected views, and to pursue truth with unfaltering footsteps, even at the hazard of having to retrace many a year's travel, it may be in a wrong direction.

Science and Civilization are almost synonymous terms they are, at any rate, co-relative. The first attempt of the savage to make himself a weapon, or to produce fire, are but the dawnings of what may eventually become the highest condition of culture. To aid in the furtherance of scientific pursuits should be the pride of every educator, and it is quite impossible to do this, so far as Natural Science is concerned, more advantage⚫usly than by presenting for study and examination the innumerable objects that lie around us in such profusion.

Perhaps the greatest drawback to any attempt in making a collection, will arise from that sense of impermanence that characterizes the position of so many teachers. Few will feel disposed to devote time and labor towards a project the accomplishment of which requires years for anything like fulfilment. The only way to overcome this difficulty, in places where the people desire to possess a museum, is for the trustees of the school to take the matter in hand allowing successive teachers a small sum for labor and attendance. Just here a very pertinent query suggests itself. If a corporation, at considerable expense, maintains such a collection, to prove not only valuable as a school adjunct, but to be attractive to visitors, both from the town itself and from a distance, why should not the Legislature aid the undertaking with its hundred per cent. grant, as is done in the case of libraries? Railways, colonization roads, and schemes of drainage, are very well in their way, and no one grudges a reasonable expenditure upon works of the kind, but surely it would not be asking too much, were we to request from our law-makers at least the same encouragement towards the formation of local museums as is now extended to the aggregation of the often antiquated books of travel and other uninspiring literature, which find their way into our school libraries, and which so frequently fail in attracting the interest of the young-Canada Educational Monthly.

Prof. Boyle proves his faith by his works, having purchased several hundred dollars worth of specimens for use in his institution.