couch near him, terrifying him with a ferocious growling if I discovered a negro endeavouring to make his escape. One he stirs. They then bark at intervals to give notice to the of the Spanish dogs was sent after him. On coming up, chasseurs, till they come up and secure their prisoner. Each the negro cut him twice with his muschet, on which the chasseur is obliged to have three dogs, though he hunts dog seized him by the nape of the neck and secured him. with two only, and these he maintains at his own expense: He proved to be a runaway, said that he and two other he lives with his dogs, and is inseparable from them. At negroes had deserted the Maroons a few days before, and home they are kept chained, and when walking with their that the party was at a great distance from the town, but masters are never unmuzzled or slipped from their ropes, that he would conduct them to it by noon next day. except for attack. One or two small dogs called finders, In the next anecdote recorded by Dallas, the attack was whose scent is very keen at hitting off a track, accompany fatal both to the unhappy object of it and to the dog. One them. Dogs and bitches hunt equally well, and the chas- of the dogs that had been unmuzzled to drink when there seurs rear no more than will supply the required number.' was not the least apprehension of any mischief, went up to Though the breed is said not to be so prolific as the com- an old woman, who was sitting attending to a pot in which moner varieties of the dog, it is stated to be infinitely stronger she was preparing a mess. The dog smelled at it and was and hardier. It is described as of the size of the largest troublesome; this provoked her; she took up a stick and hound, with erect ears, which are usually cropped at the began to beat him, on which he seized on her throat, which points, with the nose rather pointed, but widening much to- he would not let go till his head was severed from his body wards the binder part of the jaw. The skin and coat, it is by his master. The windpipe of the woman being much added, are much harder than those of most dogs, and it is torn, she could not be saved. said that the severe correction which they undergo in training would almost kill any other description of dog; this, however, may be doubted. There are some whose nose is more obtuse, and whose frame in general is more square, and these it is thought have been crossed with the mastiff; but if the bulk of the animal has been a little increased by the cross, it is not considered that the mixture has added anything to the strength, height, beauty, or agility of the native breed. [See MASTIFF.]

When there is such discrepancy it becomes interesting to ascertain what the Cuban blood-hound is really like. A dog and a bitch, said to be of the true breed, were lately brought to this country, where, soon after their arrival, the bitch littered ten pups, one of them deformed. Here, at least, the statement that the Cuban blood-hound is not so prolific as the common dog was not borne out. Some of these pups we have seen, and we are enabled to give a description and figure of the variety. They are shorter on their legs than the English variety; the muzzle is shorter, and the animal is altogether smaller, with less of the hound about it than the English blood-hound has; the height is about two feet; the colour generally tawny, with black about the muzzle, or brindled like some of the Ban-dogs. They show great attachment, and are very gentle till seriously provoked, and then their ferocity is alarming,

[Chasseur with Cuban blood-hounds.]

In Cuba, the common employment of these dogs was to traverse the country in pursuit of murderers and other felons, and an extraordinary proof of their activity is recorded by Dallas, who states that the event occurred about a month before the arrival of the commissioner at the Havanna. A fleet from Jamaica, under convoy to Great Britain, passing through the Gulf of Mexico, beat up on the north side of Cuba. One of the ships, manned with foreigners, chiefly renegado Spaniards, being a dull sailer, and consequently lagging astern, standing in with the land at night, was run on shore, the captain, officers, and the few British hands on board murdered, and the vessel plundered

Spanish chasseurs with his dogs; and he relates the follow-by the Spanish renegadoes. The part of the coast on which ing instances of the strength and determined ferocity of

the latter.

The party had scarcely erected their huts when the barking of a dog was heard near them. They got immediately under arms, and, proceeding in the direction of the sound,

the ship was stranded being wild and unfrequented, the

A long straight muschet, or couteau, longer than a dragoon's sword, and twice as thick, something like a flat iron bar sharpened at the lower end, of which about eighteen inches are as sharp as a razor. The point is not unlike the old Roman sword. Such is Dallas's description of the chasseur's muschet. Our drawing was taken from a dog which had not attained its full growth,

assassins retired with their booty to the mountains, intend- indigent artizan, elicited general praise; but the extra-
ing to penetrate through the woods to some remote settle-vagant and indiscriminate applause of Mr. Lofft may well
ments on the south side, where they hoped to secure them- be considered as more injurious to Bloomfield's reputation
selves and elude all pursuit. Early intelligence of the crime, even than such contemptuous derision as that of Byron in
however, had been conveyed to the Havanna, and the his English Bards.' An edition was published in the fol-
assassins were pursued by a detachment of twelve of the lowing year at Leipzig. At Paris a translation, entitled 'Le
chasseurs del Rey with their dogs. In a few days the Valet du Fermier, was made by Etienne Allard; one was
criminals were all brought in and executed, not one of them also made into Italian; and in London appeared, in 1805,
being in the least hurt by the dogs when captured.
Agricolæ Puer, poema Roberti Bloomfield celeberrimum,
in versus Latinos redditum' auctore Gulielmo Clubbe,
LL.B., a very clever effort in imitation of the Georgics.
The fame of Bloomfield was increased by the subsequent
publication of Rural Tales, Ballads, and Songs, Good
Tidings, or News from the Farm, Wild Flowers, and
Banks of the Wye.' He was kindly noticed by the Duke
of Grafton, by whom he was appointed to a situation in the
Seal Office; but suffering from constitutional ill-health, he
returned to his trade of ladies' shoemaker, to which, being
an amateur in music, he added the employment of making
Eolian harps. A pension of a shilling a day was still al
lowed him by the duke; yet having now, besides a wife and
children, undertaken to support several other members of
his family, he became involved in difficulties; and, being
habitually in bad health, he retired to Shefford in Bedford-
shire, where, in 1816, a subscription, headed by the Duke of
Norfolk and other noblemen, was instituted by the friend-
ship of Sir Egerton Brydges, for the relief of his embarrass-
ments. Great anxiety of mind, occasioned by accumulated
misfortunes and losses, with violent incessant headaches, a
morbid nervous irritability, and loss of memory, reduced him
at last to a condition little short of insanity. He died at
Shefford, Aug. 19th, 1823, at the age of fifty-seven, leaving
a widow and four children, and debts to the amount of 2001,
which sum was raised by subscription among his benevolent
friends and admirers. In the following year, at the sale of
his MSS., that of The Farmer's Boy,' in his own hand-
writing, was sold for 147.

African Blood-hound.-On his return from Africa, the
late Colonel Denham, then major, presented two dogs and a
bitch of this variety to the royal menagerie in the Tower,
which, under the care of the keeper, Mr. Cops, then contained
a very choice collection of animals, recorded in that interest-
ing publication, The Tower Menagerie, London, 8vo. 1829.
The Major informed Mr. Cops that with them he hunted
the gazelle, and that they displayed great cunning, fre-
quently quitting the circuitous line of scent for the purpose
of cutting off a double, and recovering the scent again with
ease. They would hit off and follow a scent after a lapse of
two hours from the time when the animal had been on the
spot, and this delicacy of nose had not escaped observation,
for they were applied to nearly the same purposes as the
other varieties here mentioned, and were commonly em-
ployed in Africa to trace a flying enemy to his retreat. It
is well remarked in the work last above-mentioned that for
symmetry and action they were perfect models, and a regret
is expressed that, in consequence of their not having shown
any disposition to perpetuate their race, though they had, at
the time of making the observation, been three years in
England, there appeared to be no chance of crossing our
pointers with this breed. We agree with the writer in think-
ing that this blood so introduced would be a very valuable
acquisition. It was remarked that, of the three in the
Tower, the males were very mild, but the female was of a
very savage disposition.

BLOOMFIELD, ROBERT, an English pastoral poet, the youngest of six children of George Bloomfield, a tailor at Honington, a village near Bury St. Edmonds in Suffolk, where Robert was born, December 3, 1766. Having in early infancy lost his father, his mother obtained a scanty subsistence for her family by keeping a little school, in which he himself was taught to read. Her poverty with difficulty affording him even necessary clothing, at the age of eleven he was hired in the neighbourhood as a farmer's boy; but being found too feeble for agricultural labour, he was placed with a relative in London to become a shoemaker. With no assistance or stimulus beyond the reading of a newspaper, and a few borrowed books of poetry, of which his favourite was Thomson's Seasons,' he composed his beautiful rural poem The Farmer's Boy' in a poor garret, No. 14, Bell Alley, Coleman Street, whilst at work with six or seven others, who paid each a shilling a week for their lodging. The MS., after being offered to, and refused by, several London publishers, was printed under the patronage of Capel Lofft, Esq., in 1800; and the admiration it produced was so general that, within three years after its publication, more than 26,000 copies were sold. The appearance of such refinement of taste and sentiment in the person of an

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The works of Bloomfield have been published in 2 vols. 12mo. Hazlewood Hall,' which appeared a short time before his death, has little merit in comparison with his earlier productions. His 'Remains,' consisting of Songs, Anecdotes, Remarks on Eolian Harps, Tour on the Wye, &c., were edited by J. Weston, Esq., 1824. The Farmer's Boy, Wild Flowers,' with several of the Ballads and Tales,' are his best poems; and many critics, such as James Montgomery, Dr. Nathan Drake, and Sir Egerton Brydges, have expressed the highest admiration of their chaste and unaffected beauties. The author's amiable disposition and benevolence pervade the whole of his compositions. There is an artless simplicity, a virtuous rectitude of sentiment, an exquisite sensibility to the beautiful, which cannot fail to gratify every one who respects moral excellence, and loves the delightful scenes of English country life. Those who are charmed only with lofty and obscure conceptions, or a pompous parade of words, will find nothing to their taste in the simple descriptive poetry of Robert Bloomfield.

BLOW-PIPE. The instrument to whicht his name has been applied, was originally employed by jewellers and others in the soldering of metals on the small scale, whence it derives its name in the German language Löthrohr, from the two words 'löthen, to solder, and 'rohr,' a tube or pipe. When used for such purposes it is constructed of a simple metallic tube seven or eight inches in length, the bore of which at the larger extremity is about one-fourth of an inch in diameter, and gradually contracts as it approaches the other, where it terminates in an almost capillary orifice; and the instrument is formed by simply bending this tube at a right angle at an inch or an inch and a half from its finer extremity. In this form it is used by the workman to direct the flame of a lamp on the portion of solder to be employed, by which he is enabled to bring it readily and without loss of time into a state of fusion: the solder is placed on a fragment of charcoal, which he holds in his left hand, and upon which the flame is made to play by blowing a gentle current of air against it by means of the pipe.

Such was its sole use until the year 1738, when, as we are informed by Bergman, Antony Swab, a Swedish bergrath, or counsellor of mines, and a many of very considerable knowledge for his time, introduced it to the notice of the scientific world, by employing it in determining the nature of the metals in the various ores and minerals which came under his notice. Swab however wrote no work on the

subject, nor does it appear to have received any particular attention from any one until Cronstedt proposed his system of mineralogy, in which the arrangement is dependent on the chemical composition of the minerals. It thus became to him of vital importance for the general adoption of his system-we may almost say for its very existence-to possess some ready and simple means of determining the constituents of mineral bodies, as it was evident that those offered by the slow and laborious operations of chemical analysis could not be generally employed by mineralogists. This he found in the blow-pipe, and by the employment of fluxes in the experiments performed with this instrument, he may be considered as the founder of a new department of the chemical science. His results are to be found in his * System of Mineralogy,' the first edition of which was published in 1758, and was translated into English by Von Engeström in 1765; also in an essay by the latter, published in London in 1770 under the title of An Essay towards a System of Mineralogy,' by Cronstedt, translated from the Swedish by Von Engeström, revised and corrected by Mendez da Costa. London, 1770.

The employment of the blow-pipe in detecting the constituents of minerals being thus brought into notice, excited the attention of the chemists and mineralogists to the cultivation of this branch of chemistry, and its application to chemical analysis and to the determination of the mineralogical species. In Sweden however it still appears to have been studied with the greatest success; and it is to the chemists and mineralogists of Sweden that we are indebted for the greater portion of the information which has been received on this subject, and more particularly to Bergman, Gahn, and Berzelius. Bergman, after extending its limits by a series of original researches, in which he investigated the properties of most of the then known species of minerals, and by a more general application to chemical analysis, published the results of his observations in a treatise written in the Latin language, which appeared at Vienna in 1779 under the following title, De Tubo Ferruminatorio, ejusdemque usu in explorandis Corporibus, presertim Mineralibus. A translation of the above into English will be found in the second volume of Bergman's 'Chemical and Physical Essays,' by Dr. Cullen, London, 1788. Gahn, though indefatigable in his observations and experiments with the blow-pipe, and though far exceeding any of his predecessors both in the conception and execution of his experiments, has however left no work on the subject. As an instance of his power of detecting the presence of metallic bodies, we are told by Berzelius that he has often seen him extract from the ashes of a quarter of a sheet of paper distinct portions of copper, and that too before the knowledge of the occurrence of this metal in vegetables was known, and therefore before he could have been led from this circumstance to suspect its presence in paper. Although we cannot but feel regret at having received no work from a man so eminently qualified to instruct on this subject as Gahn, still we must consider ourselves most happy that under such circumstances the loss of the knowledge and experience of so long and laborious a life is not also to be lamented. Fortunately for science, accident, as it were, made Berzelius the medium through which this information was to be communicated to the world; and while his good fortune in thus having it in his power to add another to the many benefits he has bestowed on mankind cannot but be envied, it must be universally felt and acknowledged that if he has been favoured by fortune he has proved himself one of the most worthy of her favour by the manner in which he has fulfilled the task assigned to him. The assiduity of Gahn in this study, together with the circumstances to which we are indebted for the preservation of his labours, cannot be better told than in the words of Berzelius himself. 'Gahn,' says he, was never without his blow-pipe, not even during his shortest journeys. Every new substance, or any thing with which he was not previously acquainted, was immediately submitted to an examination before the blow-pipe; and it was indeed an interesting sight to observe with what astonishing rapidity and certainty he was thus enabled to determine the nature of a body, which from its appearance and exterior properties could not have been recognised. Through this constant nabit of using the blow-pipe he was led to invent many improvements, and to make many conveniences, which he could have at hand whether at home or abroad: he examined the action of a number of re-agents, for the purpose

of finding new methods of recognising bodics, and this he
did in such detail, and conducted his operations with such
accuracy, that all his results may be relied upon with the
greatest confidence. Nevertheless it never occurred to him
to give a written description of his new or improved methods;
he gave himself however all possible trouble to instruct all
who were willing to learn, and many foreign men of science,
who passed some time with him, have made known his
great dexterity in this subject; but no one has communi-
cated a perfect knowledge of his methods.

'I had the good fortune, during the last ten years of the
life of this in many respects most remarkable man, to enjoy
his most intimate acquaintance. He spared himself no
trouble to communicate to me all the results of his expe-
rience, and I have consequently held it as a sacred duty to
allow nothing of this experience and of his labours to be
lost."

Such then is the origin of Berzelius's treatise, a work which must be considered as the highest authority on this subject; and as there are translations in the English, French, and German languages, we cannot too highly recommend it to the study of those desirous of obtaining a more intimate acquaintance with the uses to which the blow-pipe may be applied. The English translation is however unfortunately taken from the first edition of the text; the title is The use of the Blowpipe in Chemical Analysis, and in the Examination of Minerals, by J. J. Berzelius. Translated from the French of M. Fresnel, by J. G. Chil dren, London, 1822.

As our limits will not allow of our entering into the description of the phenomena presented by the different chemical elements and minerals, when experimented on by the blow-pipe, we must confine ourselves to a general description of the nature of the experiments performed by this instrument, and the conclusions to which it leads in determining the chemical constitution of a mineral, and consequently in recognizing to what species it belongs. For this purpose it may be convenient to class the experiments under four heads :

1. The characteristic changes produced on bodies when exposed to a high temperature.

2. The deoxidizing effect of the flame, and the reduction of metals from their ores.

3. The oxidizing effect, or the changes produced by the oxygen of the air on the body.

4. The action produced by the application of fluxes or reagents.

The first three classes are dependent on the unaided action of the blow-pipe flame, and as the total effect is produced by properties peculiar to particular parts of the flame even in the cases where fluxes are employed, it becomes a matter of great importance to possess a good knowledge of the flame itself, a description of which will therefore be first given. If a burning lamp or candle be carefully observed, it will be found that the flame may be divided into four parts, which may readily be distinguished from each other. Firstly, on the lower extremity of the flame, where it is in contact with the wick, will be seen a blue portion, which

extends from the wick and terminates at the points c fig. 1,
where the boundaries of the flame assume a vertical direc-
tion. The second most striking part of the flame is the
bright intensely luminous portion 6, which rising as it were

from out of the cup produced by the blue, ascends in the
form of a cone. In close connexion with this cone will be
observed a smaller one contained within it, of a dark
colour, and rising from the upper extremity of the wick; and
by a very careful examination it will be found that the outer
surface of the luminous cone is bounded by a thin coating
of a slightly luminous flame c b, which forms the continua-
tion of the blue ring, and increases a little in thickness as
it approaches the upper extremity.

The three cones thus enveloping each other differ not
only in their appearance, but also in their temperature and
chemical condition. Flame, as was shown by Sir Hum-
phrey Davy in the course of his beautiful and philosophical
inquiries into its nature, which terminated with the disco-
very of his safety-lamp, is gaseous matter heated to white-
ness its most striking properties are evidently its power of
communicating light and heat, and however closely these
may appear to be connected, the circumstances by which
the one may be developed to its greatest extent in a flame
is unfavourable to the production of the other. The expla-
nation of this is simple and obvious: the heat depends on
the rapidity and energy of the chemical combinations
taking place; the light on the contrary on the quantity of
the matter kept at the white heat, and on the length of
time it remains in that state. If therefore into a stream of
burning gas (to take a particular case, let it be coal gas) a
jet of oxygen be conducted, the combustion will be imme-
diately rendered more rapid, the temperature of the flame
will consequently rise, while its illuminating power dimi-
nishes, as will probably have been observed by many who
have seen the oxy-hydrogen flames, where the light is de-
rived only from the strongly heated chalk, not from the
burning gases.
On applying these views to the common
flame, the existence of the three concentric cones will be
readily understood in the exterior cone, the inflammable
gases arising from the decomposition of the burning ma-
terial come in direct contact with the atmosphere, are well
supplied with oxygen, and they consequently here undergo
a more rapid combustion than the interior enclosed portions:
here therefore will be found the hottest points of the flame.
That such is really the fact may be proved experimentally,
by holding a fine iron or platinum wire across the flame,
when it will be found to glow most strongly in the points
of its emergence from the luminous cone, and by holding
the wire at different elevations in the flame, it will be found
that the portion of the outer cone immediately above c, the
upper ridge of the blue cup, is the point of greatest heat.
In the most luminous cone the combustion is slower, and in
the interior darker portion, the gases have not yet come into
contact with the air, and are still unchanged.

If a fine current of air be now directed into the flame by
means of the blow-pipe, it will assume the appearance seen
in fig. 2 in the centre of the flame, and immediately pro-
ceeding from the orifice of the tube, a long and thin blue
portion in the position de of the figure will be seen this
corresponds with the blue cup of the natural flame. But it
was in the upper edge of this cup, in which were found the
points of greatest heat, and the same is true here also, with
this difference however, that while in the natural flame
these points were spread over a considerable circle, c c, in
the blow pipe flame they are all collected into the one point
e, where their united effect is of course proportionably great.
The reason therefore of the high temperature which may
be produced by the blow-pipe is the result of the concentra-
tion of the hottest points of the flame into a focus; and an-
other circumstance tends also to heighten this effect, that
while in the natural flame the points of greatest heat are on
its outer boundaries, and are therefore rapidly robbed of
their temperature, they here occur encased by the luminous
flame which thus protects them against the loss of tem-
perature from this cause.

The blow-pipe employed by the workman in the soldering
of metals, and constructed as was first described, cannot be
employed in these operations, owing to the collection of the
water from the condensed moisture of the breath on con-
tinuing the blast any time. This inconvenience is avoided
by making the blow-pipe of two pieces, and by interposing
between these a receptacle for retaining the water, which is
thus prevented from entering into the finer part of the pipe
where it would obstruct the current of air. In using the
blow-pipe the operator must not employ his lungs in pro-
ducing the current of air, as it would not only be detri-
mental to his health, but he would be unable to sustain the

blast a sufficient length of time to ensure the necessary
effects: it is produced by inflating the mouth with air,
which is then forced through the tube by contracting the
muscles of the cheek, and by a little practice the blast
may be thus sustained for a considerable time, the pro-
cess of respiration being unaffected, the only inconvenience
arising from the fatigue of the muscles of the cheek from
their unusual exercise. The power of being able to per-
form this depends on the individual being able to keep
his mouth inflated while he respires. After this has been
learnt, some little experience will be required to enable the
operator to regulate the strength of the blast, so as to pro-
duce the most powerful heat, as it must be neither too
strong nor too weak; in the first case the heat is diminished
in its action by an excess of air, and in the second too feeble
a flame is produced.

We now proceed to the experiments themselves to which
the blow-pipe may be applied, and we commence with those
which fall under the first class,-The changes produced
on a body when exposed to a high temperature. Of these,
four are particularly worthy of notice .-
Its fusibility.

The changes produced in its colour.

The volatization of the substance under examination. The volatization of one or more of its component parts. When the various elements or their compounds, which occur in a solid form at the usual temperature, for these alone can here be considered, are exposed to heat, there is always evidence of a force tending to overcome that cohesion of their particles to which they owe their solid form, and it is believed that by a sufficient degree of temperature any body whatever might be made to pass to the state of vapour, either immediately or through the intermediate stage of fluidity. However this may be, it is well known that the temperature at which such changes are effected varies with each element, and the point which the blow-pipe first informs us upon is, whether the body is one of those which are unchanged or not at the degree of heat capable of being produced by means of it; and according to the result we know among what class of bodies the one under consideration will be found. Nor is this mere fact the sole guide to the knowledge of the body under examination; the facility or difficulty with which the change is effected, the characters of the substance in its changed form, the appearance it assumes on being again allowed to cool, open to us new sources of information, and each must be carefully observed. Thus in some minerals the fusion is produced with ease; in others again it can only be effected slowly and by the strongest heat we can produce; while in a third case our efforts will only be sufficient to round off the sharp edge of a fine fragment.

But these are by no means the most important changes, the relations of the elements to oxygen gas being decidedly more interesting and instructive. When any substance combines with oxygen gas it is said to be oxidized, and when a compound of oxygen with any base loses oxygen, it is said to be deoxidized or reduced to a lower state of oxidation, according as it has lost the whole or a part of its oxygen. Most bodies, and particularly all the metals, are capable of undergoing the one or the other of these changes; and as by means of the blow-pipe we have it in our power to produce at pleasure the conditions under which a metal is liable to be oxidized, as well as those which are favourable to its reduction, should it be present in the form of an oxide; and as these changes are usually accompanied with striking and characteristic phenomena, the blow-pipe is thus the most powerful instrument in detecting the presence of metals, which may in many cases be extracted in their perfect metallic form from the smallest fragment of their ore.

The oxidation will be produced by holding the body before the outer extremity of the flame, where the elements being heated in contact with the oxygen of the air, are placed in the most favourable circumstances for combining with it. This takes place the more readily the further the assay is held from the flame, provided a sufficient temperature is at the same time obtained; nor is it necessary that this should be very great, since too great a heat is disadvantageous, particularly when the support is of charcoal. This process will be best performed with a pipe of comparatively large orifice, and when the material is kept at a low red heat.

The deoxidation or reduction requires a small orifice, and the substance under examination should be as much as

possible surrounded by the luminous flame, by which means it is cut off from contact with the atmospheric oxygen, and is surrounded with a glowing combustible gas, by which it is deprived of its oxygen. In performing this operation, which is infinitely more difficult than that of oxidation, particular attention must be paid to keep the assay constantly in the luminous flame, as the action is but little assisted by the charcoal on which the substance rests. Berzelius recommends the beginner to practice himself in the reduction of metals by fusing small grains of tin on charcoal, and to endeavour to keep it in that state without allowing its surface to lose the metallic glance, which it does owing to the formation of the oxide, the instant it is removed from the deoxidizing flame. This operation should first be attempted on very small fragments, as the difficulty increases with the size of the tin grains.

knife and reduced to powder in an agate mortar. This must then be washed, by which the fine and light particles of charcoal may be readily removed from the metallic particles which, if any be present, will be found in a pure metallic form in the mortar. The form in which the metal will be found depends on its fusibility and malleability: should it possess these properties, it will be formed into small thin leaves; if not, it will be found as a metallic powder. By this process the operator should be aware that the metals antimony, bismuth, and tellurium may have escaped his observation, from having been volatilized as soon as reduced, which is also always the case with selenium, arsenic, cadmium, zinc, and mercury, which can only be obtained by sublimation.

The borate of soda of commerce is never sufficiently pure for these purposes, but it may readily be obtained fit for use We now come to speak of the experiments in which fluxes by solution in pure water and re-crystallization. It may be are employed, the most important of which and their uses employed either in the form of small grains, or of powder, will be briefly described. They are, carbonate of soda, borate or it may be first fused to free it from its water of crystalof soda, the double phosphate of soda and ammonia, salt-lization. The advantages of its use in the blow-pipe are petre, boracic acid, bisulphate of potash, gyps, fluor-spar, dependent on its forming a most powerful flux, by which a nitrate of cobalt, tin, iron, lead. Of these the first three only number of otherwise refractory substances may readily be are of general use, while the others are employed to test the brought into a state of fusion. It is usual, in the first place, presence of particular bodies: we shall confine our attention to endeavour to fuse a small fragment of the assay; as, if therefore to the former, as to touch upon the particular cases this process be successful, we are able to observe the phenoin which the others may be advantageous would not only lead mena taking place during the fusion better than when it is us too much into detail, but belongs more particularly to the applied in the form of a powder; and what is the most imchemical description of the properties of these bodies. portant, we see whether the assay is partially or entirely fusible in this flux. The principal facts to be observed are, whether the fusion is accompanied with effervescence, or whether it takes place tranquilly; to examine the colour of the glass when obtained, and the changes it undergoes according as it is acted on by the oxidizing or reducing flame, and also to observe whether any changes take place either in the colour or transparency of the glass as it cools. The phosphor salt, to use the term by which it is usually designated in works on this subject, is a double salt of phosphoric acid, ammonia, and soda. It is best prepared, according to Berzelius, by adding to a solution of 16 parts of chlorate of ammonia in a small quantity of boiling water 100 parts of crystallized phosphate of soda: this latter must then be brought also to a state of solution over the fire, after which the solution must be immediately filtered, and then be allowed to cool slowly, when the double salt will be deposited as crystals. It may be considered as pure if the crystals when fused give a glass, which does not become opaque on cooling. The object of this salt is to enable us to try the action of a free and strong acid on the assay, which is best obtained by this means, as on heating the ammonia is driven off, and the acid with which it was combined is then at liberty to exercise its influence on the body tested. It is therefore a powerful agent in proving the presence of the metallic oxides, with which it frequently forms characteristic coloured salts; and it is also a good test for determining the presence of silica in minerals, the phosphoric acid depriving it of the bases with which it was combined, and presenting it in the form of a gelatinous substance.

Care should be taken that the carbonate of soda employed for these experiments be free from any impurities, particularly from the sulphate. The purest which can be purchased is the bicarbonate of commerce: if this cannot be obtained, a saturated solution of the ordinary carbonate should be taken, through which a current of carbonic acid must be transmitted, when the bicarbonate will be precipitated in the form of fine grains, which must be washed with cold water and then dried. It may be tested for sulphuric acid by means of the blow-pipe itself in the following manner:-Let a glass be formed by fusing a portion of the carbonate of soda with a small quantity of pure silica, and let the resulting glass be well acted on by the deoxidizing flame. If on cooling it retains its colourless condition, the soda may be considered free from sulphuric acid, the presence of which would be indicated by the glass assuming a yellow passing into a hyacinth-red colour, owing to the presence of the liver of sulphur. The application of soda answers two purposes: to determine whether the body is fusible in it as a flux, and to assist in the reduction of metals. The soda is best applied by mixing it in powder with the substance to be examined, which should also be in powder: the mixture is formed into a paste by the addition of a little water, a small portion of which must then be placed on the charcoal, where, after drying, it must be brought into a state of fusion. It is usual for the soda, as soon as it is fused, to be entirely absorbed by the charcoal, but it is not on that account less active: a continued effervescence is observed on the substance under examination, and its fusibility is indicated by the formation of a glass globule.

But the greatest use of soda is decidedly in promoting the reduction of metals, which it does in a most unaccountable manner. If a small quantity of the oxide of tin be placed on the charcoal, a dexterous blower, at some expense of time and trouble, will be able to obtain from it a small globule of metallic tin. If however a little carbonate of soda be added to the oxide of tin, the reduction is effected with ease and rapidity.

The influence of the soda in this operation is not under stood, but its action is constant; and Gahn has given the following process, by which the metals platinum, gold, silver, molybdenum, tungsten, antimony, tellurium, bismuth, tin, lead, copper, nickel, cobalt, and iron may be obtained, and consequently their presence detected, whenever they occur in any ore.

The assay is reduced to powder, and formed as before into a paste with the moistened soda: this must then be placed on the charcoal, and submitted to the action of a good reducing flame. After some time an additional quantity of soda must be added, and the blast must be again renewed, and this process must be repeated until the whole of the assay is absorbed by the charcoal. When this is entirely effected, those portions of the charcoal which have thus become saturated with soda, must be moistened by a few drops of water, and they must then be carefully removed with a

It now only remains once more to call the attention of all our readers, who may be in any way engaged in any manufacture dependent on the applications of chemistry, to the great advantages to be derived from the possession of some skill in the use of this little instrument. For instance, of what advantage would it be to the apothecary, in enabling him, at the cost of a few minutes, to prove the absence of impurities in the medicines he purchases-to the chemical manufacturer, to the dyer, the miner, the assayer. Nor are there any difficulties arising from the size or expense of the necessary apparatus; all that is most commonly necessary might be conveniently carried in the pocket. Nor is the requisite knowledge difficult of acquirement; nor need the individual, in order to be able to employ this instrument in a manner practically useful to himself, be a scientific chemist: it is one thing to be able to apply a particular part of a science, another to extend it by discoveries. BLUBBER [See WHALE-FISHERY.]

field-marshal of the king of Prussia, was born Dec. 16th, BLÜCHER, LEBRECHT VON, prince of Wahlstatt, 1742, at Rostock, a town near the shore of the Baltic, in the duchy of Mecklenburgh Schwerin. His father was a captain of cavalry in the service of Hesse Cassel. At an early age he manifested a strong predilection for the military profession: and, in opposition to the advice of his relatives, entered, in his fourteenth year, a regiment of Swedish