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entire width. The one to the right-hand PRACTICAL SCIENCE.
is used to contain the blowpipes in use
together with files, hammer, small anvil, 5.-THE MOUTH BLOW PIPE. microscope, &c.; and the one to the left
is set apart for the appropriate fluxes, (Continued from page 23.)
which are arranged in boxes, as already 41. A proper place to perform your ex- mentioned. These drawers are made to periments is absolutely necessary, if they pull out to a certain distance, but are preare to be extensive; and even when con. vented from falling by a piece of wood ducted upon a small scale, it is advisable fixed underneath. I always have a chair to have some place set apart for working, on my right-hand side, with a towel hangbecause your instruments are apt to get ing over the back, and a basin of water, jumbled together, and mixed with all sorts and soap placed upon the seat; this is of things; the consequence of which is, extremely useful, and sometimes absolutely that they get clogged with dirt, and are necessary, for you camot be too parnever at hand when most required. The ticular about your hands being clean, when old proverb of, " Have a place for every- analyzing some substances. thing, and everything in its place," should Latterly I have added a small shelf, be always upmost in the mind of a stu- about four inches wide, and extending dent of practical science ;” but espe- the whole length of the table, to the cially a blowpipe manipulator.
upper and back part. This is supported Those who use the blowpipe extensively upon upright pieces, and is intended for should have a table to contain all the ap- the reception of solutions in test tubes, paratus; but as I have remarked before, bottles, &c., and bottles with tests. It the student should endeavour to think for projects beyond the table, and is so made himself, and convert anything that comes that it may be removed at pleasure. If to hand to his use.
the table is required to be portable the 42. The table used for blowpipe opera- legs should be made to unscrew,
and it tions is something like a lady's worktable, will then form a box. only that it is made of deal. I have long 43. Analysis by the blowpipe can seldom been accustomed to use one with a shifting or ever be determinate, other tests must top made of sheet-iron, and covered inside be employed afterwards ; but quantitative with_white cartridge-paper pasted upon analysis would be almost as useless without it. This box is so constructed, that it fits the aid of this valuable instrument, as the upon the top of the table, by means of a blow-pipe itself would be without a flame. peg placed at each corner, which drops In analyzing an unknown substance--say, into a hole underneath. The table, which for example a crystalline body—it is usual is about thirty inches long, sixteen inches to submit it to certain operations, during wide, and forty-five inches high, has five which certain phenomena take place, drawers in front, a long one at the top, which give us an insight into its nature. and two on each side underneath it. The First, heat it in a small glass tube, closed small drawers are used to contain the at one end to ascertain what changes take articles required to be in stock, —such as place during the process; sometimes we extra nozzles and blowpipes, stock of perform this operation without the aid of fluxes, charcoal discs, lamp wicks, small reagents; while at other times we pasteboard trays in nests, for containing bine certain reagents with the substance specimens, extra porcelain capsules, and to be acted upon. Secondly, we heat the crucibles, with the lamp and such articles. body alone, before the blowpipe, in the The long drawer is kept for such speci- open air, to ascertain whether, first, it is mens as you may require for examination ; fusible ; secondly, whether it inflames; these are contained in the pasteboard trays, thirdly, whether it changes colour: fourth'abelled, arranged, and covered so as not ly, whether it boils up, or becomes larger ; to be exposed to the dust. On either side fifthly, whether it becomes volatile and of the table is a drawer which passes un- disappears altogether, or only loses part of derneath the other drawers, and is nearly its substance by the disengagement of half the length of the table, but of the volatile matter ; sixthly, the colour im.
CLOSED AT ONE END.
parted to the flame of the blowpipe ; and how careful I am not to heat the tube too lastly, any difference that may be observed suddenly; and now that the tube is heated in its exposure to the oxidating and re- by the flame of the spirit lamp, I will ducing flames. Thirdly, we heat the direct the flame upon the tube, and be substance in a glass tube, open at both sure to observe closely what takes place. ends, for three reasons ; firstly, to discover (The tube is heated over the flame of a the action of a current of atmospheric spirit lamp at first, and then by means of air acting upon it, when exposed to a high a blowpipe flame. As the heat is raised temperature ; and secondly, for the purpose the wood becomes brown, then blackish, of discovering the odour of the vapours and at last black). The blackening or given off; and thirdly, to ascertain what charring of the wood, is owing to the sublimates are produced. Fourthly, we decomposition of the ligine or woody may have to heat the substance in a tube fibre of the wood, which consists of three. closed at both ends-a process we shall elements, carbon, hydrogen, and oxygen. explain hereafter. Fifthly, we heat the There is a dense white smoke ascending substance with reagents, either in tubes, from the wood, and some portion of the or exposed to the flame of the blow-pipe glass is covered with small drops of fluid, in the open air.
and you can observe a peculiar odour
attached to the vapour issuing from the 1. HEATING BODIES IN GLASS TUBES tube. · When the heat is raised so as to de
compose the wood, a portion of the carbon, In heating any substance in a tube together with the hydrogen and oxygen, closed at one end, take the precaution to pass off in the form of pyroligneous or hold it five or six inches above the flame acetic acid, with a tarry matter, and other of the lamp at first, and then gradually volatile compounds, while another portion bring it closer to the flame, until at last of the carbon is left behind at the bottom the part where the substance itself is of the tube—this is charcoal. No doubt placed is kept in the hottest part of the you wondered why I held a small strip of Aame. The tube should be held nearly moistened blue litmus paper in the mouth horizontal at first, that is, on a level corre- of the tube ; but as you saw it turn red, I sponding with the top of the table, and suppose that you know now, it was simply then gradually sloped until it is nearly to test if the vapour was acid; and the upright; then the flame of the blowpipe result was satisfactory. If it had not should be brought to play upon the part been acid, of course the blue litmus paper where the substance to be operated upon would not have turned red. Red turmeric is placed. By adopting this method we paper would have turned yellow, had it shall be able to ascertain if the body is been employed in the same manner. an organic or inorganic substance; whether We will now perform another experiit is acid, alkaline, or neutral ; if it is vola- ment, and also test the frames as before, tile, or not; whether it sublimes readily; but with a different result. the character of the sublimate, whether a [Experiment 2.] I have placed a small metal or not, &c. We will now make paring of my nail-the readiest substance some experiments, for the purpose of at hand, for illustration-in the tube, and ascertaining the character of certain shall proceed as in the experiment above. substances, commencing with organic [Does so, and the portion of nail is first bodies.
observed to twist about and curl up, then 44. Organic bodies, when heated in a to swell up and as it were to boil, becomclosed tube before the blowpipe flame or ing in the mean time a semi-fluid tarryotherwise, blacken, and we also observe looking mass three or four times the size other changes takes place; but let us see of the portion used.] You observe that for ourselves.
there is a similar white vapour produced, a [Experiment 1]. Here is a glass tube similar tarry-looking substance on the which you observe is closed at one end, sides of the tubes, and that the residue is and you see that I place a piece of wood black and carbonaceous as in the former about the size of a barleycorn in the experiment. You could not distinguish lower part of the tube. You also see one tube from the other if the mouths
of them were closed with corks and given you to examine; but remove the corks and the odour given off by the one containing the animal body will soon enable you to decide the matter, for it is far more disagreeable and powerful than the odour given off by the vegetable body. The former is like the odour of a burnt feather, and the latter like that of burnt paper.
When I introduced a piece of yellow turmeric paper into the mouth of the tube you observed that it turned brown, clearly indicating that the vapour was alkaline. Red litmus paper would have turned blue. Now the alkaline nature of the vapour is owing to the presence of ammonia, which is almost invariably produced when any nitrogenous compound is decomposed by heat. I suppose you know that any body containing nitrogen in com- the charcoal immediately deflagrates or is bination with other substances, is called a consumed when it reaches the saltpetre.] nitrogenous compound; but if you did If you reduce the charred residue of not, please to remember the fact, because almost any organic body to a coarse powwe shall have to use the term very often. der, and employ it instead of the charcoal,
45. To distinguish organic from inorganic the same appearance will be observed. bodies.-In examining bodies before the blowpipe, with a view to determine
COMMON SENSE.--Fine sense and exwhether they are organic or inorganic,
are not half so valuable as you should always observe the residue, as
There are forty men of this will at once settle the matter. If,
wit for one man of sense ; and he that after the body has been exposed to the will carry nothing about him but gold, flame, either in a tube or out of one, the will be every day at a loss for want of residue has only become blackened, you readier change. may be certain that it is not an organic body; because organic bodies always leave a charred mass behind, and moreover they Swift.-Swift having paid a visit at give off copious vapours during their de- Sir Arthur Acheson's country-seat; and composition. I will perform an experi- being, on the morning of his return to ment to show you that organic substances his deanery, detained a few minutes longer are generally consumed by fire, when than he expected at his breakfast, found, brought into contact with heated salt- when he came to the door, his own man petre.
on horseback, and a servant of Sir Ar[Experiment 3.]-Take a retort stand thur's holding the horse he was to ride which has a movable slide (a), and then himself. He mounted, turned the head of place a small Berlin porcelain evaporating his horse towards his own man, and asked dish (6) upon it. Place a few grains of him in a low voice if he did not think he nitrate of potass (nitre) in the dish, and should give something to the servant who apply the heat by means of an Argand held his horse; and if he thought five gas-burner (c), supported on a heavy base, shillings would be too much? “No, sir, and furnished with a flexible tube of vul- it will not, if you mean to do the thing canised India-rubber (d), or by means of handsomely,” was the reply. The dean a spirit lamp. When the nitre is melted | made no remark upon this; but when he and red hot, take a pinch of coarsely- ) paid his man's weekly account, wrote powdered charcoal between your finger under it," Deducted from this, for money and thumb, and drop it into the heated paid to Sir Arthur's servant for doing nitre. [The experiment is performed, and your business—five shillings."
SIGNIFICATION OF CHRISTIAN NAMES.-TREASURES.
SIGNIFICATION OF CHRISTIAN NAMES.
(Continued from page 117.)
He who jests upon the deformities of Nature, upbraids the God of nature.
FLATTERY is the base coin to which vanity gives currency.
What is wanting in reason, upon an argument is too often supplied by rage.
The reading of most men is like a wardrobe of old clothes-seldom used.
A PINE coat is but a livery, when he who wears it discovers no higher talents than a footman.
THE real use of talking is almost lost to the world by the excessive custom of lying.
COWARDS are like sorry horses; they have just mettle enough to be mischievous.
THE stoical scheme “supplying wants by lopping desires," is like cutting off our feet when we have no shoes.
SETTLE your disputes yourselves if you would make an end of thom-would you prolong them, call in lawyers.
CRUELTY is so contrary to human nature that it is branded with the scandalous term inhumanity.
Our passions are like convulsive fits, which though they make us stronger for a moment, yet leave us much weaker afterwards.
CHARLES the Fifth used to say, “that the cle. mency of a prince is like the heat of the sun, which hardens dirt, while it softens wax."
MANY who seem to carry the liberty of the subject highest, serve them like trouts-tickle them till they catch them.
CHEYNE observes, that “water is the most natural and wholesome of all drinks, quickens the appetite, and strengthens the digestion most."
PROFANENESS in conversation too commonly passes for wit; whereas it is in truth a certain sign of the want both of judgment and manners.
THE ancients personified and even deified health. Salus was the goddess of health and safety, to whom there were erected several temples dedicated at Rome.
A WISE man thinks none his superior wilo has done him an injury, for he has it then in his power to make himself superior to the other, by forgiving it.
A KING is to be envied for nothing so much as the supremacy of his power to do good; and if his inclinations be but equal to his power, he must necessarily be the happiest man in his realm.
ANTISTHENES wondered at mankind that in buying an earthen dish, they were careful to sound it lest it had a crack, yet so careless in choosing friends as to take them flawed with vice.
The best way to prove the clearness of our understanding, is by showing its fralts; as when a stream discovers the dirt at the bottom, it convinces us of the transparency and purity of the water.
applied as soon as possible, will scarcely ever USEFUL RECEIPTS.
fail.-J. S. Norwich.
Method of taking Profiles in Black--Procure Writing Inks. It may be stated that, as a gene- a wooden frame, about a foot square: divide each ral rule, writing inks containing logwood do not side into six portions, and stretch across strings flow readily from the pen. A solution of creosote
at equal distances before marked, so as to make in rectified spirit of wine, or pyroligneous acid, is in all thirty-six squares.
Purchase some of the the best preservative of ink from mouldiness.
black paper used by artists (three half-pence a Pharmaceutical Journal
sheet) and on the white side rule thirty-six equal To make Casts of the appearance of Ivory.
squares corresponding to those on the frame.
Then desire the person Make a paste of isinglass and brandy with some
sit about three yards powdered egg-shells finely ground; press it while
from you, and in such a position that you see warm in your mould, which should first be well
their profile through the squares of your frame. oiled, and leave till dry.-E. A. COPLAND,
Then sketch on your paper with the ruled lines Windsor.
the profile as you see it through the squares, and
draw it on yours correspondingly. Then cut out New mode of Stopping Hiccup.-Dr. Piretty
what you have sketched, and stick, with black side appears to have found a very simple means of
up on a piece of card. This is a capital way for arresting this disagreeable and often very obsti
one who has no artistic taste to take sketches of nate symptom. It is sufficient to squeeze the
views, busts &c.-E. A. COPLAND, Windsor. wrist, preferably that of the right hand-with a piece of string, or with the fore-finger and thumb To wash Lace.-At page 203 of the 5th volume, of the other hand,
Old Series, Family Friend, is given a receipt for Varnish for Furniture.—To one part of virgin washing lace, which is not quite correct, as the white wax add eight parts of oil of petroleuni; edge would lose its new appearance, and the lace lay a slight coat of this mixture on the wood with
the gloss; which faults will be entirely obviated a badger's brush, while a little warm; the oil
by the following process :--Cover a bottle (the will then evaporate, and leave a thin coat of wax,
larger the better) with a linen (not calico) case which should afterwards be polished with a coarse
made to fit tight; roll the lace round it, taking woollen cloth.-H. L. B.
care that the edge is kept smooth, and that the
head of the succeeding round covers it; tack the To transfer the Patterns of Lace and Coloured lace if there are several lengths in the slightest Muslin on Paper.-Make a solution of yellow possible manner, and without any knots. When bichromate of potash in water (distilled), as the lace is all rolled round the bottle, cover, it much as it will take up; soak the paper on this tight with linen. Then rub it well with soap (the for about a quarter of an hour; lay the lace, &c., best curd), or, if very dirty, make a strong lather, on the paper when dry, place a piece of plate and let the bottle remain in it for a night ; rinse glass on it and expose to the light of the sun, it well by pouring water over it. If possible, exthen wash the paper in pure water, and dry in pose the bottle to the sun, watering it frequently, blotting paper.-F. C. S. D'ALQUEN, Brighton. and also to the night air, and let it dry thoroughly
before you open it. Avoid hot water, as it deTo clean Boot-tops.--Take a pint and a half of
stroys the look of newness. I enclose a small sour milk, one ounce of oil of vitriol, one ounce
piece which I have had for fifteen years and which and a half of compound tincture of lavender,
has always been washed according to the above half an ounce of gum arabic, one ounce of lemon
direction.-E. B. juice, and the white of one egg. Mix well, and apply with a sponge as usual; another form is as
To fix the solid Brass Letters to Window Glass.follows,- a pint and a half of sour milk, one
As these letters sometimes fall off the plate glass ounce of cream of tartar, and of alum and
or other windows, after long use, we have been oxalic acid, each half an ounce. Mix well, and
requested by several correspondents to give a apply as above.-KAF.
receipt for a cement, by means of which they
may be reattached; we give four : 1. Take Beautiful Ornament for a Room. -Dissolve in
fifteen parts of sandrach and gallipot-resinvarnish, seven tumblers, in which is some warm water,
five of drying oil, and five of oil and essence of sulphate of iron half an ounce, copper half an turpentine mixed : mix well, and then add ten ounce, zinc half an ounce, soda half an ounce, parts of Spanish white and dry white lead.-2. alumine half an ounce, magnesia half an ounce, Take fifteen parts copal varnish, five of drying and potass half an ounce. Pour them altogether oil, three of oil of turpentine, two of essence of in a large dish, and stir with a glass rod; place turpentine, five of animal glue dissolved in a the dish in a warm place free from dust or from
water bath, and ten parts of hydrate of lime: being shaken. Most beautiful crystals will shoot
mix well.–3. Take fifteen parts of copal varnish out all over, forming a splendid ornament.
and colophane resin, five of oil and essence of E. A. COPLAND, Windsor.
turpentine, two parts of isinglass in powder, The Sting of a Bee.-In most cases the person three parts of iron filings or blacksmith's cinders, stung can instantaneously obtain relief by press- ground and sifted, and ten parts of washed ing on the part stung with the tube of a key. earth, ochre or rotten stone.-4. Take nifteen This will extract the pain, and the application parts of copal varnish and gum lac mixed, five of aqua ammonia (common spirits of hartshorn) parts of drying oil, three parts of a strong soluwill immediately remove it. The poison being tion of caoutchouc or gutta percha, seven parts of of an acid nature, is at once neutralized by the tar oil, and ten parts of Roman cement and application of this penetrating and volatile alkali. | plaster of Paris in powder, mixed : Do not apply A small quantity introduced into the wound on too much of the cement to each letter, and press the point of a needle, or fine-nibbed pen, and the letter firmly and evenly against the glass.