the sticks to market; the present price in Dacca is about twelve shillings the hundred weight, and it is brought from the distant country of Asam! The best lac is of a deep red colour; if it is pale and pierced at the top the value diminishes, because the insects have left their cells, and consequently, they can be of no use as a dye or colour, but probably they are better for varnishes.

The insect and its cell, has gone under the various names of gum lac, lac tree, in Bengali, lac sand; by the English it is distinguished into,-1. Stick lac; which is the natural state from which all the others are formed ;-2. seed lac, is the cells separated from the sticks;-3. lump lac, is seed lac liqnified by fire, and formed into cakes;-4. Shell lac, is the cells liquified, strained, and formed into thin transparent laminæ in the following manner; separate the cells from the branches, break them into small pieces, throw them into a tub of water for one day; wash off the red water and dry the cells, and with them fill a cylindrical tube of cotton cloth, two feet long and an inch and a half diameter, tie both ends, turn the bag above a charcoal fire; as the lac liquifies twist the bag, and when a sufficient quantity has transuded the pores of the cloth, lay it upon a smooth junk of plantain tree (musa paradisiaca Linnæi) and with a strip of the plantain leaf draw it into a thin lamina, take it off while flexible, for in a minute it will be hard and brittle; the value of shell lac is according to its transparency.

This is one of the most useful insects yet discovered, to Europeans or natives. The natives consume a great quantity of shell lac in making ornamental rings, painted and gilded in various tastes, to decorate the black arms of the ladies, and formed into beads, spiral and linked chains for necklaces, and other ornaments for the hair.

Sealing-wax.-Take a stick and heat one end of it upon a charcoal fire, put upon it a few leaves of the shell lac, softened above the fire; keep alternately heating and adding more shell lac, until you have got a mass of three or four pounds of liquified shell lac * upon the end of your stick; knead this upon a

In this manner lump lac is formed from seed lac.

wetted board, with three ounces of levigated cinnabar; form it into cylindrical pieces, and to give them a polish, rub them while hot with a cotton cloth.

Japanning.-Take a lump of shell lac, prepared in the manner of sealing-wax, with whatever colour you please; fix it upon the end of a stick; heat the polished wood over a charcoal fire, and rub it over `with half melted lac, and polish by rubbing it even with a piece of folded plantain leaf held in the hand, heating the lac, and adding more as occasion requires; their figures are formed by lac. charged with various colours, in the

same manner.

In ornamenting their gods and religious houses, &c. they make use of very thin beat lead, which they cover with various varnishes, made of lac charged with colours; they prepare them, it is said, with allum and tamarinds; the leaf of lead is laid upon a smooth iron heated by fire below, while the varnish is spreading upon it; to imitate gold leaf they add turmerick to the varnish. This art is only known to the women of a few families.

Cutler's Grindstones.-Take of Ganges sand three parts, of seed lac washed one part; mix them over the fire in an earthen pot, and form the mass into the shape of a grindstone, leaving a square hole in the centre; fix it on an axis, with liquified lac; heat the stone moderately, and by turning the axis you may easily form it into an exact orbicular shape; polishing grindstones are made only of such of the sand as will pass easily through/muslin, in the proportion of two parts sand to one of lac. This sand is found at Rajamahal; it is composed of small, regular, crystaline particles, tinged red with iron two parts, to one of the black magnétic sand described by Muschenbrook.

The stone-cutters make their grindstones of a crystalline stone with black iron specks (corund) beat into powder, and mixed with lac, in the same proportions as with the sand; the coarse for cutting, and the sifted powder for polishing. These grind-stones cut down iron very fast, and when they want to increase its power, they throw sand upon it, and let it occasionally touch the edge of a vitrified brick. The same composition is formed upon sticks for cutting stones, shells, &c. by the hand.

Painting. Take one gallon of the red liquid, from the first washing of shell lac, strain it through a cloth, boil it for a short time, then add half an ounce of soap earth (fossil alkali); boil an hour more, and add three ounces powdered load (a straw coloured bark); boil a short time, let it stand one night, and strain next day; evaporate three quarts of milk without cream to two quarts, upon a slow fire, curdle it with sour milk, and let it stand for a day or two; then mix it with the red liquid above mentioned; strain them through a cloth, add to the mixture an ounce and a half of allum, and the juice of eight or ten lemons; mix the whole, and throw it into a cloth bag strainer. The blood of the insect forms a coagulum.with the caseous part of the milk, and remains in the bag, while the limpid acid water drains from it; the coagulum is dried in the shade, and is used as a red colour in painting and colouring.

Dyeing. Take one gallon of the red liquid prepared as in the preceding page, without milk; to which add three ounces of allum; boil three or four pounds of tamarinds in a gallon of water, and strain the liquor.

Light Red.-Mix equal parts of the red liquid water and tamarind water over a brisk fire; in this mixture dip and wring the silk alternately, until it has received a proper quantity of the dye. To increase the colour increase the proportion of the red liquid, and let the silk boil a few minutes in the mixture. To make the silk hold the colour they boil a handful of the bark, called Load, in water; strain the decoction, and add cold water to it; dip the dyed silk into this liquor several times, and then dry the silk. Cotton cloths are dyed in this manner, but the dye is not so lasting as in silk.

Spanish Wool.-The lac colour is preserved by the natives upon flakes of cotton dipped repeatedly into a strong solution of the lac insect in water, and dried.

Here I ought to have described the utilities of this body, as practised by Europeans, but I am not master of the subject, and shall be very glad to see it done by an abler hand. The properties of bodies should be as fully described as possible, for therein consists the principal utility of natural history. The present mode of describing natural productions

merely as materiæ medicæ, pictoriæ, &c, is in my opinion highly injurious to the subject, trifling, unbecoming a natural historian, and is the cause of a great evil.

To be added. After the grind-stones, the gross remains after making shell lac is formed into balls, polished and painted for boys and men to play with, as our boys do with marbles. Perhaps in this consists the secret art of making the European marbles.

Added after Dying. The dye is used in colouring that red powder, with which the Hindus bespatter one another in their holy festival time.

DESCRIPTION OF THE PRASS TREE.

Root and Trunk.-The root is large, branching, and spongy. There are three varieties of this plant, which seem principally to depend on the circumstances of their situation; that which grows in the rich soil of Bengal is a tree of the first magnitude, with a large erect long stem; what grows on the hills seldom rises higher than twenty feet; the other variety is found in the thick forests, climbing the highest trees, with a woody stem as thick as the arm.

Leaves. The leaves are alternate and ternate, with long petioles; the lobes are ovate, oblique, obtuse, and venose, with two short, and the middle petiole long.

Flowers.-The flowers are of the papilionacious kind, large, red, and pendulous, disposed in crowded, irregular, fasciculated spikes, terminating the young branches; the flowers appear before the leaves.

Calyx. The perianthium is a short urceolate gibbose, coriaccous, bi-labiate tube; the superior lip is ovate and entire, the lower lip tridentate.

Corolla.-The petals are above two inches long, equal, and of a scarlet red colour; the standard is ovate, acute, and reflexed; the wings are lanceolate, acute, and lunulate; the keel is broad, half orbiculate, acute, shut above and bifid below.

Stamina. The filaments are diadelphous, nine united to the point and one distinct; the antheræ are simple and very small.

Pestillum.-The germun is compressed and tomentose, with a short pedicle, the style is subulate, longer than the fila

tuse.

Pircepium. The ligumen is about five or six inches long, and two inches broad, tomentose, gibbose, deciduous, thin, flexible, and diaphanous every where but at the point, where it becomes ligneous, and never contains more than one seed!

Semen. The seed is orbicular, thin, compressed, of a red colour, and about an inch in diameter.

Use. The petals, as they fall from the tree are collected, and are of great use in dying red colours. The natives wound the tree to procure a red astringent gum (called chunigum) used in medicine; the bark is tough and is in commou use as rope and twine. The wood is of a red colour, but of no particular excellence. The roots are dug up, and cut into junks

Since writing the above, I have been favoured with a sight of the Hortus Malabaricus, where this plant is described under the name of Plaso, vol. vi. p. 29. The Malabars ascribe properties to this plant very different from the natives of this country. The author says the wood and leaves are used in their ceremonies; the fruit in powder expels worms, and the bark, with dried ginger, is given in morsu viperino.

THE Hindoos have since time immemorial not only excelled their neighbours in the management of metals for useful and curious purposes, but they are even familiarly acquainted with alloys unknown to our practical chemists.

Among those in general use that have drawn the attention of Europeans living in India, are the alloys for the gurry, and the Biddery ware.

The gurry is a disk of a cubit and upwards in diameter, about half an inch in thickness in the centre, but decreasing towards the circumference, where it is scarcely more than one-fourth of an inch. It is used to mark the divisions of time, by striking it with a wooden mallet. The sound is in general remarkably clear, full, and loud, when it is properly managed. In common they are suspended on a triangular pyramid made of three bamboos tied together at top. They are used in all large cities, at the cutwal's choultry, at the houses and cutcheris of great men, at the main guard of every battalion, and head-quarters of every detachment of troops. Some commanding officers have them even near their doors, to the annoyance of their visitors, whose ears are not

so blunted and insensible as their own. In short, they are the regulators of time and business over all India. The exact proportion of the compound of which they are made I do not recollect, but I believe it is somewhat variable, as the gurries are prized according to the places where they have been manufactured.

The Biddery ware is used particularly for hooka-bottoms, and dishes to hand betel about to visitors, where more precious metals are not attainable. It is of a black colour, which never fades, and which, if tarnished, may be easily restored. To relieve the sable hue it is always more or less inlaid with silver. It is called Biddery ware from the place where it was originally, and I believe is still exclusively, made; for though the people of Bengal have utensils of this kind, I have no where seen any new ones for sale, which would be the case were they manufactured there.

Biddery is a large city, about sixty miles N.W. from Hyderabad, formerly the seat of mighty kings, and one of the largest, or best places of the Dekan, belonging to the Nizam. It is situated on the eastern brink of a table-land, which is about 100

feet above the level of the surrounding country, and from S. to N. six to eight miles in diameter. The place is fortified has high walls and extensive outworks, particularly to the northward; but whether strong, or otherwise, I am not competent to judge. I found them very badly guarded; as is generally the case in the fortified places belonging to the native powers of India.

As I had been always very desirous of learning the composition of the Biddery ware, and could get no information of it at Hydrabad, I requested Captain Sydenham, then resident at that court, to favour me with a dustuk (order) to the governor of Biddery, (which place I was to pass on my way to join the detachment at Jaulna), to assist me in getting the desired knowledge. I must observe here, that it is not only extremely difficult in general, for travellers, but almost impossible, without much money, to acquire any information on a subject of the most indifferent nature, without the concurrence and actual support of the head-man of the place. At Biddery the jealousy against Europeans of all classes is carried so far, that none are allowed to enter the gates of the city, except such as are in the service of the Nizam, and stationed in the fort. It happened fortunately that the chief of that place had some favours to ask of Captain Sydenham, and Mr. Russell, his assistant, whose kind assistance in promoting my inquiries on this and all other occasions I have gratefully to acknowledge: so that I received the dustuk without much delay, just as I ascended the table-land. On producing it at Biddery some of the manufacturers were immediately sent to me in the choultry, under a guard of peons, with the strictest orders that they should inform me of the whole and every part of their mystery. I wished to go to their houses; but as this had not been mentioned in the order, and as they lived in the city, I could not obtain permission. The men who attended me complained of want, in an employment which in former times had been the means of subsisting a numerous class of their own cast, and of enriching the place, but which now scarcely yielded food for five families that remained. They are of the goldsmith cast, which, together with some of other handicrafts, is the lowest of all

sudras, though they wear the brahminical string.

At their first visit they brought nothing but a lump of their compound used for casting their ware, and a few vessels which they had just in hand, for inlaying them with silver, an operation which they conceived would be of all the most attractive to a curious fringi. As the metal in this state was divested of all but its natural colour, I recognized it immediately as a compound of which its greatest portion is tin. It contained of this metal twenty-four parts and one of copper, jóined by fusion. I was herein not a little disappointed, as I had always understood that it was made of a metallic substance found on the table-land of Biddery, and which, as I never had made any experi ment with a view of discovering its composition, I flattered myself might be a new mineral. . In coming along I really had found also a lithomarga, which resembled the common Biddery ware in colour and appearance; and it was probably this that had given rise to the account which former travellers had given of that substance, as the mineral used for the ware manufactured at that place.

T

The business of their second visit was to cast, or to make, before me a vessel of their ware. The apparatus which they brought with them on the occasion consisted of a broken earthen pot, to serve as a furnace; a piece of bamboo about a foot long as a bellows, or blow-pipe; a form made of clay, exactly resembling a common hooka-bottom; and some wax, which probably had been used by several generations for the purpose for which it is yet employed.

The first operation was to cover the form with wax on all sides, which was done by winding a band, into which the wax was reduced, as close as possible round it. A thin coat of clay was then laid over the wax, and, to fasten the outer to the inner clay form, some iron pins were driven through it in various directions. After this had been dried for some time in the sun, the wax was liquified by putting the form in a place sufficiently heated, and discharged through the hole, by which the melted metal is poured in to occupy its place. It is scarcely necessary to say, that when the metal is sufficiently cooled the form is bro

ken, and the vessel found of the desired shape.

Colouring the ware with the standing black, for which they are celebrated, is the next, and in my opinion the most remarkable operation. It consists in taking equal parts of muriate of ammonia and saltpetre earth, such as is found at the bottom of old mud walls in old and populous villages in India, mixing them together with water, and rubbing the paste which is thus produced on the vessel, which has been previously scraped with a knife. The change of colour is almost instantaneous, and, what is surprising to me, lasting.

The saltpetre earth of this place has, when dry, a reddish colour, like the soil about Biddery. It is very likely that the carbonate, or oxide of iron, which it contains, is essentially necessary for the production of the black colour. The muriate and nitrate of lime, which is in considerable proportion in all earth from which saltpetre is manufactured in India, may be perhaps not an useless ingredient in this respect.

The hooka-bottoms of this ware happen sometimes to get tarnished, acquiring a brownish, or shillering colour, which is easily removed, and the black restored, by rubbing the whole surface with a little oil or butter.

As nothing looks handsome in the eyes of an Indian, but what is glittering with gold or silver, it may be imagined that their hooka and betel dishes, which are chiefly used on festive occasions, are not left destitute of these ornaments; they are chiefly decorated with silver, in the form of festoons, fanciful flowers, and leaves. Sometimes I have seen a little gold interspersed.

The way of inlaying them is very simple; but of course as tedious as can well be imagined, and could be only practised where time is of little value. The parts of the projected figure are first cut out in silver leaf, which are placed in a piece of broken earthenware before the artist, who cuts with a pointed instrument the same figure on the vessel, applies the silver leaf, piece after piece, and gently hammers it into its place.

silver leaf, and in this I have never seen

them mistaken.

They do their work very expeditiously, and will make any figure on copper with the greatest nicety, according to the sample which is laid before them.

Note. Mr. Wilkins informed Dr. Heyne that the Biddery ware is likewise manufactured in Benares, and he thinks that zinc is used as an alloy in that part of India. I examined a piece of a metal statue, which Mr. Wilkins considered as Biddery ware; it was zinc alloyed with a very little copper.-T.

ANALYSIS OF THE CHINESE GONG.

By Thos. Thomson, M.D. F.R.S.

The Chinese gong is a large circular instrument, somewhat similar in shape to a tambourine, excepting that it is entirely of metal, and that the face is not flat, like the face of a tambourine, but somewhat convex. The metal of which it is composed has exactly the appearance of bronze. It varies in thickness in different parts, from the one-fifteenth to the onetwentieth of an inch in thickness. The surface is irregular, and bears evident marks of the hammer; yet the metal is brittle, and very elastic. When broken it has a granular texture, and its colour is rather whiter than any part of the surface exposed by means of a file.

This brittleness of the gong, although it had obviously been made under the hammer, naturally suggested the idea that it would be found malleable at some temperature between that of the atmosphere and a red heat; and I was going to undertake a course of trials in order to determine the point: but Dr. Wollaston informed me that he had already made the experiment, and found the gong quite malleable at a temperature considerably below that of a red heat. He had been induced to undertake his experiments in consequence of a gong belonging to Sir Joseph Banks having cracked. Dr. Wollaston determined the ev position of the metal, made a quantity of similar alloy, mended the crack, and restored the tone of the instrument. The crack, however, afterwards extended, as always happens in brittle and very elastic bodies.

Every body, I presume, knows that the gong is used as a kind of substitute for a