16. Analysis of Pyrophyllite of Spaa. By M. Rammelsberg (Pogg. Annalen, lxviii., 505).-The analysis afforded, silica 66.14 alumina 25.87, magnesia 1·49, lime 0-39, water 5·59 = 99-48.

17. Analysis of Talc of Rhode Island and Steatite of Hungary. By M. A. Delesse (Rev. Sci. et Indust., xxv., 107).—The tale of Rhode Island occurs in large clear foliated masses. It has two optical axes intersecting at a small angle; density = 2·5657; after calcination = 1·64. Hardness = 1; after calcination = 6, so that it scratches glass, although with some difficulty. It exfoliates when heated. On analysis it afforded silica 61.75, magnesia 31.68, protoxide of iron 1.70, water 4.83 99.96.

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18. On a new Hydrosilicate of Alumina. By MM. Damour and Salvetat (Ann. de Ch. et de Ph., 3e Ser., xxi., 376).—This mineral occurs massive in nests in a brownish clay near Montmorillon (Vienna). It has a soapy feel, and a pure rose colour, and becomes plastic in water. Composition, according to Damour, silica 50.04, alumina 20·16, sesquioxide of iron 0-68, lime 1·46, potash 1.27, magnesia 0-23, water 26.00. It is hence allied to Halloysite.

19. Philippsite and Gismondine. By M. Marignac (Ann. de Ch. et de Phys., 3e ser., xiv., 41).-Marignac separates these species, which Kobell and Brooke had united. Under Gismondine he includes specimens having an octahedral form, and rarely mammillated, and faces not striated; and under Philippsite, those whose crystals have a rectangular prismatic form terminated by a four-sided pyramid, with the faces striated in two directions oblique to one another. Density of Gismondine 2.265, of Philippsite 2.213.

20. On the Composition of Heulandite. By M. Damour (Comptes Rendus, xxii., 926; Annuaire de Chim., 1847).—Damour has detected in Heulandite a portion of soda and potash which simplifies the formula. His analysis gives, silica 59-64, alumina 16.33, lime 7.44, soda 1.16, potash 0.74, water 14·33 = 99.64. Hence, this mineral differs from stilbite only in the proportion of water.

21. On the Identity of Osmelite and Pectolite (Annuaire de Chem., 1848, p. 166).-An analysis by M. Adam indicates that osmelite of Breithaupt is identical with Kobell's pectolite. It contains, silica 52.91, lime 32.96, protoxide of manganese 1.44, soda 6.10, potash 2-79, alumina and oxide of iron 0.54, water 4.01.

22. On Disterrite, from the Valley of Fassa in Tyrol. By M. Von Kobell (Jour. of Prak. Ch., xli, 154; Annuaire de Ch., 1848, 173). Disterrite crystallizes in hexagonal prisms, cleaving parallel to the base, and has a pearly lustre on the terminal faces, with a vitreous lustre on the sides of the prism. H = 5 to 63 (Breithaupt's scale); sp. gr. 3.042 3.051; Composition, silica 20-00, alumina 43.22, peroxide of iron 3.60, magnesia 25.01, lime 4.00, potash 0.57, water 3.60.

23. On Glaucophane. By M. Hausmann (Jour. of Prak. Ch.,

xxxiv., 238; Annuaire de Chimie, 1846, p. 271).-Glaucophane comes from the island of the Cyclades, and resembles indicolite. It has a prismatic foliated structure, a pure blue colour seen by refraction; sp. gr. 3.103 3.113; powder feebly attracted by the needle. The mean result of two analyses is as follows:silica 56-49, alumina 12-23, protoxide of iron 10-91, protoxide of manganese 0.50, magnesia 7.97, lime 2.25, soda with traces of potash 9.28 99-63. It resembles Wichtyne from Finland in composition.

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BOTANY.

24. Chinese Method of Colouring Green Teas.-During a visit which I paid to a tea manufactory in the city of Shanghae, I happened to meet some merchants who came from the celebrated green tea district of Wheychou. Thinking this a good opportunity for obtaining some information regarding the mode of colouring green teas, and, as I was accompanied by Mr M. Donald, an excellent Chinese scholar, I had some questions put to them on this subject. They would not acknowledge that any colouring matter was used in the manufacture of their teas, and pretended to laugh at the idea of such a thing. They said, moreover, that they were aware the practice of colouring was a common one about Canton, where inferior teas were made, but that they never coloured their teas in Wheychou. They then skilfully enough tried to change the subject by telling us, that we should not give credence to all we heard, "If we did so," said they, we would make some strange mistakes with regard to the productions and manufactures of your country. For example," they continued, "it is commonly reported that you buy your teas in order to convert them into opium, and resell them in that form to us. Now, we do not believe that you do that; and neither should you believe all you hear about the colouring of our green teas." After giving us this sage advice, they asked us very gravely, how we used this tea in England,—and if it was true that we had the leaves boiled and beat up with sugar and milk!

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It is, however, a difficult thing to get the truth out of a Chinaman: and from information which I had received, I knew quite well that our Wheychou friends were deceiving us in the present instance. Shortly afterwards I had an opportunity of seeing the whole process; and as it is one of considerable interest, I noted it down at the time with great care, and now send you a copy of my observa

tions.

The superintendent of the tea makers managed the colouring part of the business himself. In the first place, he procured a portion of indigo, which he threw into a porcelain bowl, not unlike a chemist's mortar, and crushed it into a fine powder. He then burned a quantity of gypsum in the charcoal fires which were roasting the tea. The object of this was to soften the gypsum, in order that it might VOL. XLVII. NO. XCIV.-OCTOBER 1849. 2 c

easily be pounded into a fine powder in the same manner as the indigo had been. When taken from the fire it readily crumbled down, and was reduced to powder in the mortar. These two substances having been thus prepared, were then mixed up in the proportion of four parts gypsum to three of indigo, and together formed a lightblue powder, which, in this state, was ready for use. This colouring matter was applied to the tea during the last process of roasting. The Chinese manufacturer having no watch to guide him, uses a joss stick to regulate his movements with regard to time. He knows exactly how long the joss stick burns, and it, of course, answers the purpose of a watch. About five minutes before the tea was taken out of the pans, the superintendent took a small porcelain spoon, lifted out a portion of the colouring matter from the bason, and scattered it over the tea in the first pan; he did the same to the whole, and the workmen turned the leaves rapidly round with their hands, in order that the colour might be well diffused.

During this part of the operation, the hands of the men at the pans were quite blue. I could not help thinking, that if any drinker of green tea had been present during this part of the process, hist taste would have been corrected; and, I hope, I may be allowed to add, improved. It seemed perfectly ridiculous, that a civilized people should prefer these dyed teas to those of a natural green. No wonder that the Chinese consider the nations of the West as "barbarians." One day Mr Shaw, a merchant in Shanghae, asked the Wheychou Chinamen their reasons for dyeing their teas; they quietly replied, that as foreigners always paid a higher price for such teas, they, of course, preferred them; and that such being the case, the Chinese manufacturer could have no objection to supply them.

I took some trouble to ascertain precisely the quantity of colouring matter used in the process of dyeing green teas; certainly not with the view of assisting others, either at home or abroad, in the art of colouring, but simply to shew green tea drinkers in England, and more particularly in the United States of America, what quantity of gypsum and indigo they eat or drink in the course of a year. To 14 lb. of tea were applied rather more than an ounce of colouring matter. For every hundred pounds of green tea which are consumed in England or America, the consumer really eats more than half a pound of gypsum and indigo; and I have little doubt, that in many instances Prussian blue is substituted for indigo. And yet, tell these green tea drinkers, that the Chinese eat dogs, cats, and rats, and they will hold up their hands in amazement, and pity the taste of the poor Celestials.

In five minutes from the time of the colour being thrown into the pan, the desired effect was produced. Before the tea was removed,

* An incense burner.

the superintendent took a tray and placed a handful from each pan upon it. These he examined at the window, to see if they were uniform in colour; and if the examination was satisfactory, he gave the order to remove the tea from the pans, and the process was complete. It sometimes happened, that there was a slight difference amongst the samples; and in that case, it was necessary to add more colour, and, consequently, keep the tea a little longer in the pan.—(R. F., Athenæum, No. 1136, p. 790.)

ZOOLOGY.

25. Additional Observations on a new living Species of Hippopotamus of Western Africa. By S. G. Morton, M.D., Penn. and Edin., Vice-President Acad. Nat. Sci. Philadelphia. (From the Journal of the Acad. Nat. Sci. Philadelphia, 1849.)—This new species of Hippopotamus was first described by Dr Morton in the Proceedings of the Academy, for February 1844, and there named H. minor.* As this name was previously used by Cuvier for a fossil species, it is now changed to Hippopotamus (Tetraprotodon) Liberiensis. The animal is slow and heavy in its motions, and weighs 400 to 700 pounds. It lives on the river St Paul's, a stream that rises in the mountains of Guinea, and passing through the Dey country and Liberia, empties into the Atlantic to the north of Cape Messurado. The description of the animal by Dr Morton is drawn from two skulls in his possession, the only specimens which have hitherto been brought from the African coast.—(The American Journal of Science and Arts, vol. viii., No. 22, p. 152.)

ARTS.

26. The Portland Vase.—An account of the Portland Vase was published by the late Mr Wedgwood, the father of the potteries, and an accomplished philosopher; it is, like its author, truthful and accurate. On this famed vase being offered for sale, Wedgwood, considering that many persons, to whom the original was unattainable, might be willing to pay a handsome price for a good imitation of it, endeavoured to purchase it, and for some time continued to offer an advance upon each bidding of the Duchess of Portland, until, at length, his motive being ascertained, he was offered the loan of the vase on condition of withdrawing his opposition. Consequently, the Duchess became the purchaser at the price of eighteen hundred guineas. It is stated that a limited number of copies were sold at fifty guineas each, and that the model cost five hundred guineas; probably, the celebrated

*See Silliman's Journal, xlvii., p. 406, where woodcuts are given.

Flaxman was the artist who was so liberally rewarded. Sir Joseph Banks and Sir Joshua Reynolds bore testimony to the excellent execution of these copies, which were chased by a steel rifle, after the bas-relief had been wholly or partially fired.-(Curiosities of Glass-making, by Apsley Pellatt, p. 21.)*

MISCELLANEOUS.

27. On the Tricks of Fire-eaters and Conjurors.—M. P. H. Boutigny, whose beautiful experiments on the spheroidal condition of water created so much interest at the meeting of the British Association at Cambridge, has lately been pressing his researches on heat in a somewhat novel direction. He has now proved that metals in a melted state have, in a remarkable manner, the repulsive force of incandescent surfaces, and that the tricks of fire-eaters and conjurors belong to a high class of physical facts. He says, "I have made the following experiments:—I divided or cut with my hand a jet of melted metal of five centimetres, which escaped by the tap. I immediately plunged the other hand into a pot filled with incandescent metal which was truly fearful to look at. I involuntarily shuddered, but both hands came out of the ordeal victorious. * * * * I shall of course be asked," he continues, "What are the precautions necessary to prevent the disorganizing action of the incandescent mass? I answer none. Have no fearmake the experiment with confidence-pass the hand rapidly, but not too rapidly, in the metal in full fusion. The experiment succeeds perfectly when the skin is moist, and the dread usually felt at facing masses of fire supplies the necessary moisture; but by taking some precaution, we may become truly invulnerable. The following succeeds best with me: I rub my hands with soap, so as to give them a polished surface; then, at the instant of trying the experiment, I dip my hand into a cold solution of sub-ammoniac saturated with sulphurous acid." The experiment has been tried by Boutigny with melted lead, bronze, and cast-iron.-(Athenæum, No. 1138, p. 842.)

* One of these beautiful copies is preserved in the Natural History Museum of the University of Edinburgh.