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ported to all parts of the world for polishing steel and other metals. The clay from which the scouring bricks are made is composed of an immense number of silicious shells of Infusoria, only to be distintinguished by the aid of a powerful microscope. . Now, silex or flint is much harder than steel, and, it being an elementary rule in mineralogy that the harder minerals are capable of cutting the softer, the roughness of the steel is easily removed, or, in other words, a fine polish is produced.

If you place a piece of steel under a microscope the polish will be found to consist of minute, equal scratches, produced by the hardness of the broken shell. These shells lie probably at the mouth of the river, between high and low watermark, mixed with mud, sand, &c., forming a species of "Delta," and are washed up and carried on by the rising tide and deposited at the reflux. That this mud, impregnated with Infusoria, exists near the mouth of the river, and above low water-mark, is obvious. Firstly, because the deposit, being specifically heavier than water, could not have been carried far without falling to the bottom unless a much greater mechanical force were exerted on it than the sea under ordinary circumstances would be capable of exercising. Secondly, because it is a well-known fact, that the sea is never disturbed by any external force, such as wind, tide, &c., more than twelve feet below its surface-the deep sea being always perfectly calm except where undercurrents exist; and yet at the lowest tide, with the surface of the sea unruffled, the deposit is steadily brought in. Still further, in support of this view of the case, there are extensive mud flats at the entrance of the river, many of which are laid bare at low water; whereas a little further on each side the coast consists of sand and rocks.

The fact of the clay being unfit for scouring purposes a mile or so below the town, and the same distance above it, is easily explained. The Parrot is one of those rivers into which the tide rushes with considerable force, and, passing over the mud flats in question, takes up mechanically, not only the socalled clay, but also coarse sand, small stones, and a variety of other things; but, having a winding course of sixteen miles to pass over, before arriving at Bridgewater, these last, together with the heavier refuse, are for the most part deposited lower down; the lighter shells, together with the mud and some of the sand, are carried up further, and deposited in the immediate neighbourhood of the town. Hence it is evident that it can only be collected from a limited space along the river's bank, as the coarser substances being mixed with it, its use for giving a high polish is destroyed.

This scouring-brick clay is not, however, entirely peculiar to Bridgewater. It is, for instance, also found on the banks of the Vistula, near Dantzig, in Prussia, where, when the river overflows, as it does

about once in twelve months, it leaves a deposit very similar to our own; but, though extending over a space of several miles, the deposit (being only two and a half inches in depth) is quite useless for commercial purposes. The long intervals between the periods at which the river overflows is also an insurmountable difficulty. At Bridgewater the clay is obtained in the following manner: the bank is cut away perpendicularly, so that a horizontal bed is left on which the clay is deposited at the rate of six feet in twelve months. Much more is deposited in dry weather than in wet, in consequence of the large amount of fresh water which finds its way into the river in a rainy season, and which is, of course, specifically lighter than salt. The clay is afterwards dug up, well mixed and ground, the object of which is thoroughly to unite all the constituent parts, and to make it a uniform quality. It is then moulded into bricks, dried, and burned.

There is another substance essentially the same as Bath-brick, namely, tripoli, in speaking of which Sir Charles Lyell says:-"There are a variety of stony deposits in the earth's crust now proved to have been derived from plants and animals of which the organic origin was not suspected until of late years even by naturalists. Great surprise was therefore created by the discovery of Professor Ehrenberg, of Berlin, that a certain kind of silicious stone, called Tripoli,' contained millions of remains of organic beings, which the Prussian naturalist refers to microscope infusoria." Ehrenberg estimates that in the Bilin Tripoli there are 41,000 millions of individuals of the Gaillonella distans in every cubic inch, which weighs 220 grains, or about 187 millions in a single grain. It is but fair to state that there are those who believe the fossil remains of the tripoli to be of vegetable origin, and by them they are called Diatomacea. Tripoli is obtained in large quantities from Bilin, in Bohemia.

In conclusion, it may be interesting to remark that during a short stay at Madrid, curiosity having prompted me to inquire the price of a "Bath-brick," I found it no less than fifteen pence of our money. MARTIN HENRY PAYNE.

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THE

RURAL NATURAL HISTORY.

HE "march of intellect" is a very good thing in its way, but it is a thing which, when much talked about, becomes a positive nuisance. The steam-engine and the electric telegraph are useful, though not by any means ornamental; but it unfortunately happens, that as these novelties become recognized, old manners and customs fall into disuse, and are looked upon with a contempt which they certainly do not deserve. The floral games with which the "merrie month of May" was wont to be ushered in, are now things of the past; Saint Valentine even, in rustic districts, is put on the shelf, and, in towns, is commemorated by hideosities which must make the worthy gentleman very much ashamed of his devotees. In short, nothing remains as it used to be; no, not even the weather. It is, however, somewhat comforting to reflect that the progress of education has not quite banished from the popular mind the traditions which have been handed down from bygone ages. Many quaint old customs, curious legends, and more curious practices, still exist in out-of-the-way places, and before these are all swept away by the advancement of learning, it may be well to record a few of them for the benefit of a future generation.

In Essex, or at least in some parts of it, there exists a superstitious belief, that if the blossoms of the hawthorn (Crataegus oxyacantha) are brought into the house, death, or, at any rate, serious illness, will ensue in some member of the household; and well do I remember the indignation which I, in more youthful days, excited in a worthy relative, by conveying, unconscious of the results to be expected, a splendid hawthorn bough, one mass of blossom, within her portals.

In a village in Buckinghamshire a case of epilepsy recently occurred. Medical aid was employed, but, after a short time, abandoned, and a travelling packman was consulted. He suggested two methods of cure, both of which were faithfully tried. The first was, that the afflicted person should procure a jay: every morning fasting she was to chew a piece of bread, and then give it the bird to eat, and on the death of the poor creature, the fits would cease. To make assurance doubly sure, another remedy was also tried, viz., a silver ring to be worn on the ringfinger as an "amberlet" (amulet?), to be subscribed for and presented to the patient, without her previous knowledge! The point of the joke lies in the fact, that this mode of treatment was announced by the invalid herself!

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Here, too, the Great Mullein (Verbascum Thapsus) is vaguely said to be "good for colds," and bears the names "Rag-paper" and "Poor-man's Flannel." There is also an idea that Mezereon, or "Mazalum " (Daphne Mezereum), can be budded from wood-laurel (D. Laureola) "by them as knows how." In Essex, dock leaves are applied to the blisters raised by the sting of the nettle, and are believed to be efficacious in removing the smart.

A gentleman of my acquaintance had killed, near Wycombe, a slowworm (Anguis fragilis), and was carrying it home on a stick. A sagacious peasant, however, warned him to be careful, for the thing couldn't die till the sun set, "no, not if you was to cut it in pieces"!

Of course the popular errors regarding snakes are in full force here; though, to his honour be it recorded, one man confided to me his belief, that

common snakes wasn't poisonous, only adders and vipers," which seem to be regarded as two different things.

Occasionally there seems to be an exercise of poetical imagination which one could hardly expect in the rustic mind. Thus, a poor woman, lamenting to me over some misfortune, said,—“Well, sir, you know the sparrows say, 'Cheer-up, cheer-up,' and I must try and cheer up' too."

One more remedy, and I have done. The following was communicated to me by a medical man, a native of Lincolnshire, who received it from a farmer in that county, who had tried it, and had found it efficacious when medical aid had failed:-" A cure for ague.-Get up at sunrise on the first day of the month and go into a field, having first emptied all your pockets; take with you the carving-knife which you have bought and used yourself. Search for an ant-hill, and when found, plunge the knife into it, and stir round as many times as you have had aguefits; then lay yourself flat on your stomach, with your face towards the sun, and having placed your mouth over the hole which you have made with the knife, breathe into it as many times as you have had the fits. You may then go home, taking care to speak no word until you have breakfasted, and the cure is complete." This last injunction, of silence, is by no means unimportant, as the cure is known to have entirely failed when this has been broken. Pills made of spiders' webs are also given for the same complaint.

Here I will, for the present, close my selection from "Oldwivesfabledom;" assuring such of my readers as fail to appreciate my choice, that if Science be absent from the narration, there is no lack of genuine Gossip to flavour it withal. B.

"Might not the very admiration of nature have been an act of worship," continued Lancelot. "How can we better glorify the worker than by delighting in his work?"-Yeast.

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plants, called respectively Corchorus olitorius and Corchorus capsularis, belonging to the same natural order as the lime tree, from the inner bark of which the bast is derived, so well known to horticulturists as the material of "bast matting." The fibre as prepared for the market might easily be mistaken by the novice for hemp, but it is softer, more glossy, weaker, and, under the microscope, more transparent, more slender, and apparently with thinner cell-walls.

The Jute plant is an annual, varying in height from four to twelve feet, the stems being from threequarters to an inch and a half in circumference. Its leaves are alternate, elongated, and serrated at the edges, the two lower serratures being lengthened out into a slender thread. The flowers are small, and have five yellow petals. The fruit consists of a capsule, containing numerous seeds. It is sown in April or May, and flowers in July or August, when it is ready to be cut, if its fibres are to be obtained. Jute is largely cultivated, especially throughout the Bengal Presidency, where its domestic manufacture occupies almost all classes of Hindoos. It has been estimated that the annual weight of Jute manufactured in India is not less than 118,000 tons. Not less than 50,000 or 60,000 tons of Jute fibre are annually exported to Great Britain, and the total production in India is estimated by Dr. Forbes Watson at not less than 300,000 tons. This is, therefore, a very important staple in the commerce of India.

The great trade and principal employ of Jute in India is for the manufacture of gunny chuts, or chuttees, for making bags. These gunny bags are the common coarse bags in which Indian produce is brought to the English market, and are even more familiar to us than the fact, that they are called "gunny-bags," and are made of Jute. This industry pervades all classes in Lower Bengal, and penetrates into every household. Men, women, and children, find occupation therein. Boatmen in their spare moments, husbandmen, palankeen-carriers, and domestic servants; everybody, in fact, being Hindoos -for Mussulmen spin cotton only-pass their leisure moments, distaff in hand, spinning gunny twist. Its preparation, together with the weaving into lengths, forms the never-failing resource of that humble, patient, and despised of created beingsthe Hindoo widow-saved by law from the pile, but condemned by opinion and custom for the remainder of her days literally to sackcloth and ashes and the lowest domestic drudgery, in the very household where once, perhaps, her will was law. This manufacture spares her from being a charge on her family-she can always earn her bread.

There is scarcely any other article so universally diffused over the globe as the Indian gunny-bag. All the finer and long-stapled Jute is reserved for the export trade, in which it bears a comparatively high

price. The short staple serves for the local manufactures, and, it may be remarked, that a given weight of gunny-bags may be purchased at about the same price as a similar weight of raw material, leaving no apparent margin for spinning and wearing. The stems or stalks of the Jute crop are of almost equal value with the fibrous portion. They are beautiful white and straight stems, of a light brittle wood, somewhat like willow switches, and have a multitude of uses amongst the natives, such as for the manufacture of charcoal for gunpowder and fireworks, for the formation of fences and enclosures, for pea and similar cultivation, and for the construction of those acres of basket work which the traveller remarks near every native village.

That portion of the hank of fibre next the rcot, or where it has been held in the hand during preparation, being always more or less contaminated with bark and other impurities, is cut off for about nine inches. These ends are sold to paper makers, and wrought up into thick coarse fabrics. The manufacture of Jute whisky from them was tried experimentally, by subjecting them to the process of conversion into sugar with sulphuric acid, and afterwards fermenting. The produce greatly resembled grain whisky. Old and worn-out gunny bags, both in India and Great Britain, are torn up and converted into most excellent white paper. Rauwolf states that one of the Jute plants, called the Jew's mallow (Corchorus olitorius), is sown in great quantities in the neighbourhood of Aleppo as a pot-herb, the Jews boiling the leaves to eat with their meat. In India, the leaves and tender shoots are also eaten by the natives. Occasionally, also, the dried plant is employed by the native doctors in medicine. There is one little branch of industry connected with Jute which was not long since mentioned in the " "Technologist," and is confined, doubtless, to a little knot of British speculators :"There are some people who make a good trade even by buying up the bags that have held sugar, and selling them again to the ginger-beer or 'pop' manufacturers, who first boil them to get out all the saccharine matter to sweeten this popular beverage, and then dispose of the bags to the mat makers." Hence we may reasonably conclude that it is no trifling matter which is alluded to in the inquiry,— What is Jute?

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"It is all very well to laugh at book-students of nature, but they carry that about with them which gives an interest to every flower, cloud, and stone they see. They see the object, and then, by the magic of association, the true beauty, fitness, history, which surround and accompany it, reveal themselves. A leaf or a bird is but a letter in the great book, which is read only by those who can put letters that is, who have the faculty of associatogether; tion."-Jones's Holiday Papers.

PHOTOGRAPHIC GOSSIP.

SEVERAL valuable novelties are now on the eve

of coming into practical use by which photography may attain popularity as a book-illustrating medium. Hitherto the processes have all been more or less imperfect, because they were too complicated, troublesome, or incapable of rendering the gradations of tone, or were only adapted for reproducing works executed in lines, or because, requiring considerable assistance from the engraver, they were too costly. Mr. Woodbury's new Photo-Relief Printing Process" is exceedingly simple, renders the delicate gradations of a "negative" from nature, and requires no aid from either artist or engraver.

You will readily perceive that white paper, visible through layers of semi-opaque material, appears lighter or darker according to the thicknesses of these layers. Thus, for instance, a mixture of gelatine and lamp-black, placed on a white surface, so that it increased gradually in thickness, would range from the white of the paper through deepening gradations of gray into black. On this simple principle the "Photo-Relief" process is based.

To a sheet of glass a piece of polished tale is made to adhere with moisture. Four ounces of Nelson's opaque gelatine, dissolved in twenty ounces of water, clarified with white of egg, and filtered through muslin, is mixed with sixty grains of bichromate of ammonia, dissolved in half an ounce of warm water, to which a bluish tint has been given with a little transparent pigment. The mounted talc is coated with a smooth uniform film of the above mixture, and, when set, it is removed from the glass, and placed, face downward, on a piece of blotting-paper, to enable the operator to carefully clean the uncoated side. The tale is then laid upon a negative in the usual way; on it is placed another sheet of glass, and the three are fastened together with elastic bands. It is next exposed to light falling upon it through a condenser until the requisite effect is produced on the film, when it is taken from between the two glasses and placed in hot water. Where the negative was most opaque, and the light consequently acted least, the bichromated gelatine dissolves away. Where the negative was most transparent, and the light, consequently, acted most, the gelatine is unaffected by the hot water; and so, in the same degrees in which the light acted, parts of the gelatine surface are more or less dissolved, and parts remain more or less unaffected. You at once see that when taken from the hot water there must be upon the talc an impression from the negative in which what should be the darkest parts are represented by being highest in relief, and what should be the lightest parts by not being in relief at all. To get an intaglio from this, a sheet of soft metal (a mixture of type

metal with lead) is placed over the talc, the two are put between two perfectly true planes of steel, and hydraulic pressure is applied at the rate of about four tons to each square inch of surface. In less than a minute we get the required intaglio, sharp, clean, and perfect; while the gelatine relief is uninjured, and may be frequently used again.

The intaglio is now placed in our printing-press, which, in appearance, is a little shallow box with a hinged lid. In the lid of this box there is a sheet of plate-glass, and at the bottom of it there is another, which can be raised or lowered by screws working through the bottom of the box. On the lower glass we place our metal impression, close the lid, and turn the screws until every part of the intaglio is in close contact with the upper glass in the lid, which is straightway opened and turned back. We now take our "ink," which is the aforesaid gelatine and lamp-black, or any other suitable pigment, fill up the intaglio to one level surface with it, place our paper on it, shut down the lid, wait about half a minute, open the box, and take out what appears to be an ordinary photograph, the only apparent difference being a slight effect of relief in the darkest parts, which decreases and almost disappears as the image dries. To render prints so obtained permanent, they may be immersed in a solution of alum, and afterwards rinsed in water.

A method of printing photographs precisely similar to the above in its main features, but in which the intaglio is obtained by the electrotype process while the print in relief is wet, has been published by Mr. Swan, of Newcastle, and we have seen very beautiful photographs produced by this gentleman's invention.

In each of the above cases the prints are obtained separately, and to use type with them is clearly out of the question; but another new process of hardly less value is now being introduced by Mr. Hancock, of Lewisham, by which photography produces electrotypes to be used as ordinary wood engravings are used. The specimens we have examined of this process, printed with type by Mr. Watson, of Hatton Garden, are extremely beautiful. Although it is only applied to the reproduction of drawings or engravings in lines, Mr. Hancock's process has all the value claimed for the glyphographic, graphotype, and other similar substitutes for wood-engraving, combined with much greater simplicity, certainty, and ease of working. We can easily conceive how an artist's drawing or a line engraving may be photographed, and from the negative a print obtained with degrees of relief by the use of bichromated gelatine as in the process used by Mr. Woodbury. After this it is not less easy to understand how an electrotype may be obtained in the way Mr. Swan adopts, and so we get at a process which, if not Mr. Hancock's, would at least serve the same J. W. W.

purposes.

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