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PRACTICAL SCIENCE.

5. THE MOUTH BLOW-PIPE.
(Continued from page 352, Vol. I.)

26. The charcoal used for blowpipe operations should be well burnt, free from bark and cracks, and tolerably heavy. The best kind is that made from the wood of the pine, willow, or elder, but if there is any difficulty in procuring these kinds, select the best pieces from any ordinary heap of charcoal, and prepare them as follows.

Take a small, thin, and narrow saw, and saw your charcoal into pieces about an inch square, then divide each piece crosswise into three, and scoop out a small place, about a quarter of an inch wide and the eighth of an inch deep. Some persons use charcoal borers to cut out the piece, but the end of a small grooved chisel or a broad brad-awl will answer the purpose. When all the pieces are thus prepared, brush away any dust that may remain by means of a hand-brush, and pack them in boxes which must be kept in a dry place. 27 To use the charcoal discs.-Bend a thin slip of tin-plate so as to form a kind of hook, and then fasten the charcoal disc under it. The method of doing this, is shown in Figs. 11 and 12. The end of the tin Fig. 11. slip being held between the forefinger and thumb

of the left hand the substance to be analysed is placed in the cavity in the charcoal, which is seen in Fig. 11., and the flame of the blowpipe directed upon it. If the charcoal splits and throws out sparks, or burns with a flame it is useless, and should therefore be thrown away, and another piece used. 28. To use the platinum foil.-Procure a piece of platinum foil,

Fig. 13.

Fig. 12

the width of the figure

in the margin, and two inches long or more, turn up one corner as in the figure above, and place the substance to be heated under it.

29. To use the platinum wire.-Take a piece of platinum wire, two inches long and of the same thickness as the accompanying figure, bend one end into a kind of ring, and having moistened it, dip it into some powdered borax, and hold it over the flame of a spirit-lamp until the borax fuses, and fills up the cavity. When any

substance requires to be analysed, it is affixed to the borax by moistening it, and then the two are fused together in the oxidating flame (§ 22, p. 351, Vol. 1.) As these wires are constantly required, it is better to have three or four of

them, and when they become too

Fig 14. short from use to be held in the fingers, they should be fixed in a cork, or what is still better, fused into a piece of glass.

30. The platinum spoon is required sometimes when a substance is heated with fluxes, or when it is too much in quantity to place upon a piece of foil. It is better to have one provided with a cover, which should fit tightly, or have some pegs to prevent it slipping off. The great advantage of platinum vessels over every other, is their being able to stand a high heat with fusing, and their not being easily acted upon by the substances undergoing analysis. A platinum spoon will cost about ten shillings, and a crucible from fifteen shillings to £2 10s., or more.

31. The platinum tongs are used to hold small specimens of substances which require to be exposed to a high temperature in the blowpipe flame. These may be easily made by an ingenious person rivetting two small strips of double platinum foil upon the two ends of a piece of stout iron wire, about a foot long, bent thus

By pressing the narrow part, the two blades of the tongs will approach each other.

32. Fine copper wire, or brass wire, when bent in the shape of that shown in the accompanying figure, is sometimes very useful, and as we proceed in our experiments with the blowpipe, we shall have occasion, to refer to it.

Fig. 15.

33. Fluxes are used to assist in the fusion of bodies, or facilitate their decomposition before the blowpipe, and should always be

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tray is required to catch any small specimens that may fall during the process of analysis, and should be kept covered with a sheet of white paper.

40. When analysing any substance, we should never use too large a portion, because it requires too great a heat. The best size is the following: for simple analysis; and if fused with borax, the bead of the latter should not exceed this .

analysis of substances by means of the

In our next we shall commence the

blow-pipe.

ARTIFICIAL FLOWERS AND

FEATHERS.

procured as pure as possible and kept in bottles, corked or stoppered, and properly labelled both on the cork, or stopper, and the bottle, otherwise your fluxes will become worse than useless through neglect. Berzelius, and other chemists, use fluxboxes about nine inches long, an inch deep, and one inch and a half wide. This long, narrow box is divided into nine compartments, each having a tightly fitting lid, and the whole secured by a general lid, fastened with hooks. The objection that attaches to these flux-boxes, is the high price; and when you can manage with a few wide-mouthed bottles, or some test tubes, or even pill-boxes, do not spend your money upon what is really of no. great advantage. Indeed, as a student of practical science, you should endeavour to use anything that comes to hand. 34. Tongs are frequently required in the operations you will have to conduct by means of the mouth blow-pipe. They are used for removing small crucibles from the furnace, or holding substances in the flame of the blow-days, and makes them wither upon her pipe. They should be made of iron, about eight or nine inches long, with the ends curved as in the figure annexed; and the handles should be covered with string twisted around them, the same as a pair of barber's tongs.

35. The small hammer and anvil are required for testing the malleability, &c., of metals, and breaking pieces off minerals for the purpose of being analysed.

36. The polished iron spatula is used for testing the presence of copper in solution, and for mixing fluxes with powders. The platinum spatula is also used for the purpose of mixing the fluxes. A common knife will answer the purpose of the iron spatula.

37. The files are used for trying metals, trimming glass, and fitting corks to test tubes, &c. The three-edged file is used to cut glass tubing, scratching glass, and cutting glass generally.

38. The triple magnifying-glass is required to examine salts, and specimens generally.

39. The rest of the apparatus speak for themselves with respect to their use. The

BY MRS. WHITE.

FLOWERS as an ornament are se natural to woman, that we could fancy the wearing of them a primeval vanity, and Eve herself the foundress of the fashion. Milton bears us out in this idea. With an exquisite refinement, he suggests them to have been the adornments of her innocent

fall. And though we have found no mention of it elsewhere, it is certain from Solomon's Anacreontic ejaculation, "Let us crown ourselves with rosebuds before they be withered," that the ancient Hebrews, like the Persians and other Eastern nations, were in the habit of binding their brows with flowers on festive occasions.

In the palmy days of Athenian refinement and Roman luxury, flowers were used not only as personal adornments, and necessary signs and accompaniments of festivity and merry-making; but they were essential to religion, and decked the altars, crowned the priests, and filleted the heads of the victims to be sacrificed, from the Bacchanalian goat to the milk-white bull that bled in honour of Jupiter.

Hence

They were dedicated to the gods, and statues were crowned with them. Venus is sometimes represented wearing roses, while Juno holds a lily in her hand; and the antique Ceres, in the gallery of the Louvre, has her hair braided with cornpoppies and bearded wheat. With the people themselves wreaths were in daily requisition, and persons made a livelihood by manufacturing them; every occasion

had its characteristic chaplet, and every diner-out one of a different design. The exquisite could run through each shade of colour that suited his complexion; the wit (for each wreath was supposed to impregnate the wearer's brain with the qualities of the plant that composed it) might quicken his with bays; the scholarly gentleman be content, like the bachelor Horace, with myrtle; and the gay bind rosy fillets on his brow. The bride had her crown, and the corpse its garland; neither of which customs are yet extinct in all the districts of those classic regions. In Italy we read that mothers still twine chaplets of the blue flowering periwinkle on the foreheads of their dead infants; and at the wedding ceremony of modern Greeks the priest is supplied with a garland of lilies, and another of ears of corn, which he places on the heads of the bride and bridegroom, as emblems of purity and abundance. Tavernier and other oriental travellers inform us that flowers have been, and are still, used as natural ornaments in the dark tresses of Indian maids; and Moore tells us that the appearance of the blossoms of the goldcoloured campac on their black hair has supplied the Sanscrit poets with many elegant allusions.

Even the forest children of our country are not without an instinct of their beauty, and considerable skill in imitating them; some of the most perfect feather flowers are made by the savages of South America from the brilliant plumage of their birds, the colours of which have all the vivacity of floral dyes; and, as they never fade, they in this particular excel those manufactured by the nuns in Spain and Portugal, who tint the feathers artificially.

It was usually set up in front of the cap without the slightest deviation from the perpendicular. Two hundred years elapsed before the feather of the fourteenth century, which had gradually glided to the side of the cap, as we see it represented in the portraits of the eighth Harry, lost its formality in the graceful plume which afterwards became so famous as the panache à la Henri Quatre.

Strutt tells us, that toward the close of the fifteenth century, a crowd of the male sex appeared at a little distance like a forest of pine trees, waving with the summer breeze, from the towering plumes of different colours worn in their caps, either standing upright from the head, or falling negligently on one side. Henry the VIII. wore a hat of black velvet, with a white ostrich feather turning over the brim. Edward, his son and successor, retained the feather, but wore it differently.

In a picture of Elizabeth, we find this royal lady's head-dress (a strange pile of false hair, pearls, and jewellery) surmounted by an immense feather, innocent of the flexibility given to it by the present mode of preparation, or of the curl so justly admired: it looks rather like a branch of broom, the badge of the Plantagenets, than a crest for the gracing of a Tudor.

This was the period when the knightly plumes of the old nobles became converted, according to the complaint of more than one satirist of the time, into fans for their degenerate sons; these elegant trifles being as necessary to the finished appearance of an Elizabethan beau, as a clouded cane to the gallants of St. James' in Charles I.'s time: and this brings us to the black beaver and white ostrich feathers of this monarch, and the great one stuck all over with diamonds, which Oldys tells us, the favourite Buck

The use of artificial flowers was introduced into England during the reign of Edward III., whose beautiful wife, Philippa of Hainault, with the ladies of her court, courageously threw off the hideous head-ingham always wore in his hat. Subsegear of the period, and with no other addition than a chaplet of flowers, allowed their hair to ornament their faces. This fashion of wearing flowers in the hair does not appear, however, to have become general in France till 1367; and then Queen Philippa was in her grave.

About the same period we first find a feather gracing the caps of the gallants.

quently the plume became the badge of the Cavaliers, in contradistinction to the plain beavers of the Roundheads; yet such a charm was found in this graceful adjunct, that even in Cromwell's time many of his followers continued to wear the high hat and drooping feather.

The reign of the merry Monarch appears to have been, of all others, that in

which these downy aids to dress became most popular: from the king to the smallest faded dandy, the feather was an absolute necessity, and ladies also wore them in their riding-hats. Indeed, we do not find them wholly laid aside in gentlemanly costume till the close of the reign of George II., when they fell into the hands of ladies and military men, who have since retained them in possession.

At present plumes are rarely worn in England, but on state occasions and at court: but in Queen Anne's time, Addison, writing of the feather head-dresses then in vogue, says he does not pretend to draw a single quill against the immense crop of plumes which is already risen to an amazing height, and unless timely singed by the bright eyes that glitter beneath will shortly be able to overshadow them." This is in 1715, and as we find two years afterwards that French or Italian flowers for the hair were then as essential to a lady's dress, in the ball or drawingroom, as a beaver and feather for the forest, we presume these redundant plumes were for the time displaced.

The hunting of the ostrich forms the most serious business of an Arab's life; while chasing the birds of paradise, and preparing the skin, affords employment to the inhabitants of many of the villages of New Guinea. Mappica and Emberbakine are famous for the numbers they export. Formerly the Chinese dealt in this plumage, and actually imposed fictitious birds of paradise on their customers, made of parrot, parakeet, and other feathers.

Ostrich feathers are prepared by many washings and rinsings, after which the backs of the ribs are scraped with a bit of glass cut circularly, in order to render them pliant; and the filaments are then curled by having the edge of a blunt knife drawn over them. The finest and whitest feathers (which are taken from the back and above the wings of the male bird) are bleached by a similar process to that which straw hats are subject to; the slightly imperfect ones are dyed of various colours, and the really dingy, black. Mounting them is the next undertaking, and this entirely depends on fashion and the purposes for which they are required. But besides the ostrich, and bird of paradise, marabou and cocks' feathers are fie

quently used in dress; the swan also con. tributes her plumage. For marabou feathers, so exquisite in their texture and airy lightness, we are indebted to the scavenger bird of India, the gigantic adjutant crane-one of the most disgusting of the feathered tribe in appearance and habits.

66

ANECDOTES OF BIRDS.. JESSE, in his "Tales of Animal Instinct," mentions a singular proof of the robin's love for its young. A gentleman," he says, "in my neighbourhood, had directed one of his wagons to be packed with sundry boxes, intending to go with it to Worthing, a place at some distance from his residence. For some time, his going was delayed, and he directed that the wagon should be placed in a shed in his yard, packed as it was, till it should be convenient for him to send it off. In the mean time a pair of robins built their nest among the straw in the wagon, and had hatched their young before it was sent away. One of the old birds, instead of being frightened away by the motion of the wagon, only left its nest occasionally, for the purpose of flying to the nearest hedge for food for its young; and thus, alternately affording warmth and nourishment to them it arrived at Worthing. The affection of this bird having been observed by the wagoner, he took care in unloading, not to disturb the robin's nest; so that the robin and its young returned in safety to Walton Heath, the place whence they were taken. The distance the wagon went, in going and returning, could not have been less than one hundred miles."

A friend of mine, whom I met in the city of Washington, some two years since, and who is a very close observer of the lower animals, related to me the following anecdote: "Six or eight years ago," said he, "I was passing the mouth of an alley leading into a vacant lot, when my attention was drawn to a group of very young children laughing vociferously. I entered the alley to see the cause of their mirth, and soon ascertained it to be a large white goose, with a narrow strip of tin bent into a hoop, and thrown over the head of the fowl, by one of the urchins. The poor

goose seemed much annoyed by the shining necklace, and ran about in every direction, trying to shake it off. I found that it was the sight of these antics, which had so much amused the little ragged juveniles. I stopped to see if the goose would unyoke herself; and while watching her, I observed some ducks in another part of the yard, and very soon a drake from among them made a great quacking, and started off toward the embarrassed goose. When near, the latter stretched her neck out horizontally, and, to my very great astonishment and admiration, the drake seized the lower part of the tin collar in his beak, the goose withdrew her head from it, and the drake immediately dropped it upon the ground; when the air rang with the plaudits of the children and the gabbling of the fowls."

A gentleman of veracity, who recently collected a number of different specimens of the humming-bird in Mexico, tells an interesting story about the manner in which birds, belonging to one of the smallest of this family, were in the habit of catching the flies that had got entangled in a spider's web. "The house I resided in for several weeks," he says, was only a story high, enclosing like most of the Spanish houses, a small garden in the centre, the roof projecting some six or seven feet from the walls, covering a walk all round, and having a small space only between the tiles and the trees which grow in the centre. From the edges of these tiles to the branches of the trees in the garden, multitudes of spiders had spread their webs, so closely and compactly that they resembled one vast net. I frequently watched, with much amusement, the cautious manoeuvres of the humming bird, who, advancing under the web, entered the various cells in search of flies. As the larger spiders did not tamely surrender their prey, the thief was often compelled to retreat. Being within a few feet of the parties, I could notice distinctly all they did. The active little bird generally passed once or twice round the court, as if to reconnoitre his ground, and then commenced his attacks by going carefully under the nets of the wily insect, and seizing, by surprise, the smallest or feeblest of the flies that were entangled in the web. In ascending the traps of the spider, great

care and skill were required. Sometimes he had scarcely room for his little wings to perform their office, and the least deviation would have entangled him in the machinery of the web, and caused his ruin. It was only the works of the smaller spider that he dare attack, as the largest rose to the defence of their citadels, when the cunning enemy would shoot off like a sunbeam, and could only be traced by his shining colours. The bird usually spent about ten minutes at a time in this enterprise, after which he would always alight on a tree near by, and rest himself awhile." It seems that the snow bird is a very affectionate little creature. Some years ago, one of them flew into a house, where, finding itself quite welcome, it remained over night. By accident, however, it was killed; and, in the morning, one of the servants threw it into the yard. In the course of the day, one of the family witnessed a most affecting scene in connection with the dead body. Its mate was standing beside it, mourning its loss. It placed its bill below the head of its companion, raised it up, and again warbled its song of mourning. By and by, it flew away, and returned with a grain or two of wheat, which it dropped before its dead partner. Then it fluttered its wings, and endeavoured to call the attention of the dead bird to the food. Again it flew away, again it returned, and used the same efforts as before. At last, it took up a kernel of the wheat, and dropped it into the mouth of the dead bird. This was repeated several times. Then the poor bereaved one sang in the same plaintive strain as before. But the scene was too affecting for the lady who witnessed it. She could bear the sight no longer, and turned away. I always loved the snow bird; but I have loved him more than ever since I heard this story.

Mrs. Child, tells a pretty anecdote about a family of swallows which she was acquainted with. "Two barn swallows," she says, 66 came into our wood-shed in the spring-time. Their busy, earnest twitterings, led me at once to suspect that they were looking out a building spot; but as a carpenter's benc 1 was under the window, and very frequently hammering, sawing, and planing were going on, I had little hope that they would choose a loca

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