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12
Study of Chlorine Substitution.

CHEMICAL Now,

July 14, 1876. a butyl-methane, HZC.C.Hg, or propyl-ethane, He notates the chloride asH.C2.CzHy, or diethyl-methane

ci ICH

C2iH 22N02=N
or dimethyl-propane-
CH3

CH2-CO.OH
H6C3
існі

The free base

C2iH22N02=N-O and as far as the nature of the paraffin is concerned one is as correct as the other ; but they are all condensed ex

CH,Co. pressions of the one true formula

In simplest terms I should say theoretically-
H3C.H,C.H.C.H.C.CH3.

Glycollic acid + strychnine – 2HO = the new base. We stay not to discuss such elements of difficulty and

A few weeks before this M. Strecker had discovered the hypothesis, but we do ask, What is the outcome thereof

same result with fuller particulars, calling the new base in the region of practical manipulation ?

Glycol-strychnine,” which it is not (CHEMICAL News, The most simple and fertile distinctions, appreciable vol. xxiv., p. 263). even to the amateur mind, are wholly ignored, while “Taking the constitutional formula of strychnine aslearned Professors are discussing methylen dispositions and polyatomic peculiarities worthy of mediæval meta

(C22H22NO2)N, physics.

then the formula of the new base is That Prof. Odling is amiably and earnestly desirous to

O extend our knowledge of isomerism no one will doubt ; but, standing before his methylen basis of terminology and classification, there are simpler matters, more within reach, which demand a juster and clearer appreciation.

(C2H22NO2)Ň When chloro or nitro substitutions subsist isomerically, the A B C of the matter is to determine where the chlorine or other radical has alighted, "whether in a methyl or in

CHZ.CO a methylen residue," &c.

Within that short interval M. Huppert falls into the Per contra, we hold that in such cases, whenever two or same error, and by digesting "monochloracetic acid with three isomers subsist, as a general rule, the isomeric methyl-guanidin to 120° for twelve hours," obtains a differences are due to the radical itself, and equally subsist crystalline result containing 2H0 more than kreatin. when the Cl or (N04) is withdrawn; and that the A B C of “ The constitutional formula of the substance glycolyl. the matter is to distinguish between a chloride and a methyl-guanidin' ischloro-radical; and, further, that this distinction is a real

NH2

OH one in fact, as well as a primary one in chemical ethics, extending also to the H of the hydride.

Some chemists take great pains to insist that in methane no difference is appreciable among the H elements; but, taking methane and mellissane as extremes, may we not fairly ask for some appreciation of the volumetric and other differences due to the H elements ? This may not be capable as yet of absolute demonstra.

ΝΗ,

CH2-.-COOH tion, and there may be difficulty in isolating the radicals without dedoublement or condensation; but the hypothesis

Kreatinin has the elements of (C6H302)CyH N,

+2H0 kreatin is deserving of respect and further research, that the 61

(C6H30.)CyH N, H elements of melissyl are condensed into one volume ;

+2HO=new base

(C6H506) CyH N. and that the added one H of the hydride or chloride

By the reađion of “ monochloracetic acid " upon mordoubles the entire volume.

phia the author obtained a crystalline basc belonging to If chemists can distinguish between the atomic volumes the same class of bodies. (solid) of O= 12'2 in acetyl, and O=7.8 in alcohol, surely Methalcohol + morphia – 2H0= they may be able to appreciate the difference between H

C34H1806 C36H2106N, CODEIA in methyl or mellissyl and the H of their hydrides, seeing

C2 Hz that one is, perhaps, one hundredsold more condensed Acetic acid, than the other.

monochloracetic acid, + morphia – 2HO= And similarly with the chlorine of chloracetyl, as com

or acetic chloride pared with that of acetyl chloride.

Whether we have ammonia, trimethyl ammonia, or tri. stearyl ammonia, who is there that doubts that these condensations do really represent so many H equivalents, Glycollic acid or

+ morphia – 2H0= both chemically and volumetrically; and whether this glycolyl chloride) hypothesis in all its bearings will pierce the clouds of prejudice, and ripen into true theory is not at all the present question, which is rather as to what advantages In the reactions with true chloracetic acid there is a have accrued from a studied disregard of the plainest facts, tendency to elimination of the Cl to a normal acetyl sub. and in illustration thereof we confine a few remarks to stitution, but this is not always the case, as with chlorchloracetic acid.

acetyl urea, and many others, At the outset, we may assume for the elements so-called

(CO),(C,H,C102)H,N2, &c. at least two isomeric forms:

M. Claus similarly trips in a recent study of sulphurea The true chloracetic acid, (C4H2C102)O.HO=C4H304C1, combinations. glycolyl chloride, (C.H304)C1=C,H,O,ci.

Urea “ hydrochloride,” (CO)2H_N HCI Dr. P. Romer digested a mixture of mono-chloracetic | Sulphurea with ethyl iodide, (CS)2H NEI acid with strychnine at 180° C. for several hours, and

» acetyl chloride, (cs) H N (C.H302)CI obtained a new base : that he combined with platinic

monochloracetic acid, chloride, giving the salt C23H240 NHCI.P.Cl2.

(CS),H.N2(C.H30.)CI

-CH3

CH;0;}C38H2103N, acetyl morphia

CH;506 C38H2:0.0N, glycolyl morphia)

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CHEMICAL NEWS,
July 14, 1876.
Development of the Chemical Arts.

13 Now who does not see that these are indeed very nor- The people may have much to learn, but the professors mal and old fashioned combinations, since ammonia with have much to unlearn. A wide demand for the bread of ethyl iodide behaves striąly similar, a matter so well truth is increasing, and the people will not be satisfied exemplified by Hofmann with the triamine rosaniline salts. with the pedantic stones of learned hypothesis. Yet, strange to say, M. Claus claims new discovery, and he believes “these additive compounds are formed through the S molecules, as exemplified in the following formulæ:

REPORT
Disulphurea ethyl-iodide.
NH2 NH2
| 1 Et

DEVELOPMENT OF THE CHEMICAL ARTS
C<

DURING THE LAST TEN YEARS.*
S-S
NH2
,
NH2

By Dr. A. W. HOFMANN.
= (CS) EH8N I.

(Continued from p. 5.)
Sulphurea ethyl-iodide.

Chlorine, Bromine, Iodine, and Fluorine.
NH2

By Dr. E. Mylius, of Ludwigshafen.
I

For many purposes, especially in the manufa&ure of <

sugar, there is required a hydrochloric acid free from sulEt

phuric acid, iron, and arsenic. Very various proposals NH2

have therefore been made for obtaining a pure acid from = (CS)2EH N21.

the arseniferous product. Thus, Houzeau,t in order to We have enlarged elsewhere on the same want of dis- obtain the acid free from arsenic distils the crude acid, crimination in respect of Armstrong's invaluable epitome adding 03grm. pulverised chromate of potash to 3 litres, of the science (sec Chemical News, vol. xxxii., p. 2), and and, in order to protect the arsenic acid produced by the could give many other illustrations, but in utmost brevity liberated chlorine from the reducing action of the hydrowe conclude with a recent discovery of "melid acetic chloric acid, he causes during the distillation a continued acid.” The others are curious, but this one is much more

stream of a solution of chromate of potash of tenfold the so, and the determination to make it an "acetic acid," in strength to be added. The escaping hydrochloric acid volves an inverse audacity, which is as marvellous as it is gas is freed from the accompanying chlorine by means of racy. The idea is that one H of acetic acid is replaced by copper turnings and is then conducted into water. This the radical or base “melamid;" but what is melamid ?

process, however, is scarcely applicable on the large scale, Thanks to Hofmann we know pretty clearly what mela

as chlorine is necessarily evolved in very considerable mine is, both as a free base and as evinced in saltic types. quantities, and its absorption by means of copper is someMelamid, then, is said to be “ melamine - H,."

what costly. P. W. Hofmann, 1 of Dieuze, on the other Now this feature may be very nice for a "residue," but hand, has successfully introduced the following methud it is very damnatory for a radical or base, having a mono

for purifying hydrochloric acid :-A vessel with a doubly equivalence; and it irresistibly tempts us to turn the perforated earthenware stopper is filled with hydrochoric whole thing upside down, when, lo! the result is no acid acid to the extent of one-third, and sulphuric acid of at all, but a “glycolyl-melamine,” behaving chemically sp: gr. 1.848 is introduced by means of a funnel capable of and typically as a substituted melamine, and acetic acid being closed. The hydrochloric acid gas, which is given probably has no existence, either before or after the re

off very regularly, is washed in a Woolff's bottle and action.

absorbed by distilled water in a receiver.

The evolution of gas ceases as soon as the sulMelamine, C3H6N6 Cy3H6N3

phuric acid has fallen to the sp. gr. 8'566, in which case it Melid acetic acid or

only retains o‘32 per cent of hydrochloric acid. The glycolyl melamine, CyzH;GN: G=(C4H304) sulphuric acid thus diluted is either employed direct in the C,HN6.CH.COOH

manufacture of sulphate of soda, or it is re-concentrated, The hydrochloride, Cy3H,GN3HCI

the expense of which amounts to 1 franc per 100 kilos. The nitrate, CyzH GN HO.NO,

As 100 kilos. of sulphuric acid thus yield 40 kilos. hydroThe sulphate,

Cy3H GN HO.SO3 chloric acid of sp.gr. 1.181, 100 kilos. of pure hydrochloric The platinate, CyzH;GNzHCI.Počlz

acid prepared by this process are 21 francs dearer than the &c.

crude acid. Fresenius, || however, remarks that the acid The sulphate or nitrate of a melid acid looks very much thus purified is not quite free from arsenic, the gas evolved like a melèe of confusion, whereas melamine gives mono containing arsenic at every stage. salts exa&ly like those above.

Bettendorfg prepares pure hydrochloric acid by utilising Truly chemists stick at nothing in order to carry out the fact that arsenious acid in a concentrated hydrochloric their preconceptions, and in sight of such results one is solution is thrown down by protochloride of tin as a brown tempted to ask Cui bono?

precipitate composed of arsenic with 1'5 to 4 per cent of It may be urged that, admitting an acetyl body most tin. He mixes the concentrated acid with a concentrated normally gives an acetyl substitution, yet that exceptional solution of stannous chloride, filters off the precipitate, cases of oxidation may transform that radical into glycocol and distils, thus obtaining an acid perfe&ly free from (or oxacetyl). And some may further contend that the arsenic. above bizarre types are models of atomic penetration and This is confirmed by Mayrhofer, but Hager** adds artistic ingenuity derived from a study of the formative and that if all the arsenic is not removed by filtration the transformative reactions involved.

distillate again becomes arseniferous. Dietz treats the They are nothing of the kind; they are fanciful plea- hydrochloric acid with sulphuretted hydrogen, whilst santries, the legitimate offspring of fanciful hypothesis; and against this torrent of passing fashion I can do no- * “Berichte über die Entwickelung der Chemischen Industrie thing but protest, and, with one leg in the grave, I can

Während des Letzten Jahrzegends."

| Houzeau, Compt. Rend., lix., 1025. Wagner, Jahresber., 1865, 251. hopefully retire with the certain convi&ion that truth will

I P. W. Hofmann, Ber. Chem. Ges., 1869, 272. be paramount, and that a better time is coming, when 1 Journ. Analyt. Chemie, 1870, 64. science will be more popularised, and simplicity of con

$ Bettendorf, Dingl. Pol, Journ., cxciv., 253. Wagner, Jahresber., ception will no longer be tabooed as necessarily superficial 1869.2007

( Mayrhofer, Ann. Chem. Pharmacie, clviii. 326. knowledge.

** Hager, Wagner Jahresber., 1872, 262.

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14
Reducing Action of Phosphine.

{

July 14, 1876. Engel employs hyposulphite of potassium for the same towards the beam, and a piece of mica upon the beam purpose. Of all these processes that of P. W. Hofmann projecting over the edge of the glass; the movement of is probably the only one used on a large scale. The pure the edge of the mica over the edge of the glass was hydrochloric acid required in the sugar manufacture is observed by a microscope magnifying several hundred chiefly prepared in certain small establishments which diameters, and measured on an ordinary scale of inches make their sulphuric acid from sulphur, or which have at and fractions laid upon the microscope stage, and observed command non-arseniferous pyrites, e.g., at Saarau, in with the left eye, while the mica was observed with the Silesia.

right eye through the microscope. (To be continued.)

The pressure representing the load was applied by means of a spring, as the observations were most con. veniently made with the movements in the horizontal

plane. The spring used was a pair of microscope pliers REDUCING ACTION OF PHOSPHINE.

having a distance of half an inch between their points,

and it was found by experiment that each one-sixteenth PHOSPHINE (PH3) exerts a powerful reducing action upon of an inch compression represented a pressure equal to sulphuric acid (SO2H02). When passed into the strong nearly 500 grs.--sufficiently near for my purposes. This acid the gas is absorbed rapidly at first, without any spring was held in place by pins in the board which visible change, but when the acid has become saturated, carried the whole arrangement. I placed one end of the and the action of the gas is still continued, the acid spring just in contact with the middle of the beam, while rapidly becomes heated sufficiently to ignite the phos. the other was free to receive pressure, the pressure being phine. If the sulphuret be kept cool by a stream of regulated by fixing a pin in the line of motion of the free water and the gas passed into it in excess, reduction to end and at such a distance as limited the compression of sulphurous anhydride, SO2, with separation of sulphur the spring to the degree which was required to produce takes place.

the pressure desired. When the pressure was 500 grs., The action may be thus represented

that is, equal to 250 grs. in each pan, the flexure equalled 3(H2SO4)+2PH3= 2502+S+2(H2PO4)+3H2. sito of an inch, and with four times the pressure the Hydric sulphide may be produced, but, if so, is decom- movement was ó inch, thus confirming the first observaposed immediately by the SO2.

tion. The observations were repeated many times, with If the action be continued sufficiently long, the acid only such differences in the measurements as would nabeing kept cool, it becomes so thick and viscid with the turally result from the nature of the experiment. separated sulphur that the vessel may be inverted without The second beam operated upon was a German disits contents escaping.

pensing beam of better quality than the above. Being of

IV. R. H. a different shape, it was found more convenient to fix one Royal College of Chemistry,

end and the middle, and apply the pressure to the free end South Kensington, July, 1876.

of the beam, using the spring in the same manner as
before, but adopting a new arrangement for microscopic

observation. A microscope slide cemented to the end of THE EFFECT OF FLEXIBILITY

the bar had diamond scratches upon its upper surface; a ON THE

similar slip laid upon it with diamond scratches upon its WORKING OF CHEMICAL BALANCES.* under surface; the end of the beam rested upon this upper By B. S. PROCTOR.

slip of glass, and was made to adhere to it with cement.

The diamond lines being on contiguous surfaces of glass were Having expressed the opinion that the degree to which a

readily brought into a sufficiently good focus for work, but a balance beam bends under its load forms an element too

lower power was necessary in consequence of the thick. important to be overlooked in any satisfactory theory of

ness of the glass through which the observation had to be its sensitiveness, I made an examination of several beams, made. A magnifying power of 125 linear was, however, good and bad, that I might first ascertain the degree to readily applied and found quite sufficient for the purpose. which bending takes place, and then calculate the effect A drop of oil interposed between the glass slips rendered which that bending would have upon the turning of the the focusing more satisfactory, but the motion rather less beam.

free. When the pressure equalled 500 grs. in each pan, I did not propose that my experiments should have any the pressure equalled 2000 grs. in each pan, the bending

the bending thus observed equalled 1-1oooth inch, and when special accuracy, such as would be required in critical examination of the relative merits of two similar beams, was, šo inch. These flexures must be halved to compare but only that they should be trustworthy, as shewing that them with those of the first beam. flexibility has an influence-an influence greatly to the tended to carry 1000 grs. on each pan, and turn with zoo

The third beam examined was one of Oertling's, indisadvantage of badly-designed beams, and not entirely to be overlooked in those of ordinary construction, but

The examination was conducted in the same which almost vanishes in the beam in which Mr. Bunge

manner as the last. The bending with the equivalent of has combined the advantages of superior mechanical

1000 grs. in each pan was 'so inch, which observation, principles with unusually good material and excellent after being several times repeated, was further confirmed by workmanship.

doubling the pressure and finding that the fexure was I commenced with a beam of no value-a common

also doubled. dispenser's box-end beam, made of brass, its length manner; being designed to carry 3000 grs. in each pan,

Finally, Bunge's beam was examined in the same between terminal bearings being 6-7 inches and its weight and turn with ddiogr. it was not to be expected that 680 grs. I bound it down against the edge of a strong fexure should be observed to a measurable extent with steel bar-a file, in fact-the box.ends forming the terminal light pressures

. I found them too small to be satisfac; supports of the beam, while the pressure was applied to the centre, and the bending estimated by the diminution torily estimated with pressures less than 2000 grs. in each of the distance between the centre of the beam and the pan; under this load the bending was sooo inch. bar. This movement was necessarily very small, and the venient form for comparison. The beams are arranged in

The following table shows tbe above results in a con. value of the observations must depend upon the extent of the order in which they were examined. Their order also this small movement being fairly estimated. After a few coincides with the development of the mechanical prinpreliminary attempts the method I adopted was to cement a slip of glass upon the bar projecting beyond its edge ciples upon which they have been designed, and indicates

progressive improvement in their working qualities, the * Read before the Newcastle-upon-Tyne Chemical Society, second being both longer and lighter, yet less Aexible than

of a gr.

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Length in Inches.

Weight in Grains.

Bending Measured at
one end under 1000
grs. in each Pan,

Fall in Centre of
Gravity of Load.

67

0'00222
O'00200

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CHEMICAL
July 4, 1876*,} Effect of Flexibility on the Working of Chemical Balances.

15 the first, as a consequence of the better distribution of its

Tutto of an ineh gr., i'; of a gr. must be the weight 52 mass; so in comparing Bunge's beam with Oertling's we raised. Now, suppose the beam to weigh 1000 grs., and have both the weight and flexibility reduced to less than that no weight had been added to b, while the same deone-third, and the figures might have been still more in flection of the pointer had taken place and the same work favour of Bunge's had it been practicable to make an consequently had been performed, the centre of gravity equal reduction in weight upon those parts of the beam of the beam must have been raised by the turning just so upon which there is little mechanical strain, but as in much as to equal zodoo of an inch gr., and that this these parts there is not much excess in the old beams, may take place the centre of gravity must be as many there is not the same scope for reduction.

times nearer the fulcrum as the weight of the beam is greater than that previously supposed to be acting at B. As its weight is 10,000 times greater, its distance will be Todoo of C B (5 inches), or o‘002 inch. If it be admitted that the distance between the centre of gravity of the beam and the fulcrum must be so small under these cir. cumstances, and smaller still when the beam is heavier of the same length, the amount of bending which I

have obtained is sufficient to interfere with its sensibility; Dispensing beam

690

and the difference in flexibility between Bunge's beam Do. better quality

635

and the forms at pressnt in use in the laboratories, is Oertling's balance

1786 0'00083 0'00041

sufficient to give Bunge's a distinct superiority in this Bunge's 5'0 616 0.00025

respect. In endeavouring to calculate the influence which the

In estimating the effect of the bending of the beam, it bending (as estimated by the preceding experiments) has beam does not fall to the same extent as the bending

must be remembered that the centre of gravity of the upon the sensitiveness of the beam, I have not attempted to follow the Algebraic method as expounded by Prof. takes place, but only to a smaller extent, and an extent Aldis, but have contented myself with the methods of centre of gravity of the load falls to the full extent of

which it is not practicable to estimate ; but the virtual plane geometry and arithmetic with which I am more

the bending. familiar, but which appear to me to tend to precisely the

In the above illustration, that of a beam weighing same conclusions. If we take c as the centre of a circle, A B and E p its

1000 grs. with its centre of gravity o'0005 below its fuldiameters, E D also representing a beam of which co is crum, and its end bearings on a line with its fulcrum

when not strained, if we suppose a bending to take the pointer, two or three simple propositions will enable us to calculate the sensitiveness of the beam and the place when loaded such as takes place in the Oertling

beam examined, then the resistance is increased from effect that bending has upon it. Let the lines A H, H B, and # 1, be drawn, the latter being perpendicular to ce. is, the weight of the pans with their load multiplied by

1000 X 0.0005 to this produa, + 2000 X 0'0004—that IB will have the same ratio to H B that h i has to A N. Wherever the point it may be placed, these ratios remain leaving out of the question the falling in the centre of

the fall which has taken place in their centre of gravity, gravity of the beam due to its bending. Thus the re. sistance due to bending would bear to the original resistance the ratio of 8 to 5.

Supposing the pointer of the Oertling beam to move o'i inch with góo gr., I calculate the centre of gravity to be 0'00027 below the fulcrum, and its resistance to the supposed movement would be thus multiplied by its weight 1786 grs. and the additional resistance due to bending would be 2000 x 0'00041. By this calculation the resistance due to bending is to the original resistance as 82 to 48.

Supposing the pointer of Bunge's beam to move i m.m. with o'i m.grm., I calculate the centre of gravity to be

0·00304 inch below the fulcrum, and its resistance con: 7

sequently 600 X 0'00304 ; while 1000 grs. in each pan = 2000 X 0.00012 (the extent of its bending), gives the additional resistance consequent upon its bending under its load. The resistance due to bending is to the

original resistance as 24 to 182.* the same. Now, let ch be the pointer deflected by a Since the distance between the fulcrum and the centre weight added to the beam at D, and having swayed the of gravity may be indefinitely decreased, the sensitive. beam to the position FG, the weight and the distance lness of the beam may be indefinitely increased provided taken together represents a certain mechanical power. If the mechanical defects of the beam do not stand in the it be a foot-pound, and the beam has come to rest at F, way, but length and its consequence-ether considerable then the work performed by this power must be a foot weight or palpable flexibility-are prominent obstacles to pound also. Foot-pounds being too large for present use, this mode of increase of sensibility, and the palpable inch grains or inch m.grms., will be more convenient. thickness of the knife edges is another obstacle. In the

If, now, be suppose c to be the fulcrum, and the centre ordinary steel knife edges, however fine they may be at of gravity of the beam, doo gr. added to D and x gr. added to B, the length of the beam being 10 inches, the

* In a balance recently designed by Prof. Mendeleef, the length of

the beam is rather less than Bunge's, and it is stated to turn with fall of D being to inch, the deflection at B will also be t'o 1•1000th gr. wien loaded with 15,000 grs.

I have not seen this inch the fall of doo gr. to inch = robog of an inch gr.

balance, nor even a detailed description of it; such particulars as I The deflection at B being inch, is to of the length A B,

have are quoted from the Pharmaceutical Journal of March 11, 1876.

Mendeleef accomplishes this extreme sensibility by adding microand for practical purposes at these small deflections also

meter scales and cross threads at the ends of the beam, and a teleado of the length of AH. Now, as i B bears the same scope for their observation-a refinement which was introduced by ratio to this,'as this y' inch bears to A B (10 inches), Prof. w. H. Mille., and which, while it greatly increases the delicacy the weight added to B has been raised vertically roo of appliances. I had not seen any notice of Mendeleef's balance til

of the observation, removes it beyond the sphere of convenient daily is of an inch, or 1ooo, and as this work done equals 1 after I had drafted my present communication.

1

16
New Method for the Detection of Copper, &c. (,

July 14, 1876.
first, they can scarcely be brought with pressure upon Hydrocyanic acid can scarcely be preserved alone, even
the agate planes without a palpable thickness being im. when enclosed in a carefully stopped bottle ; it soon
parted to them.* Those I have examined had a thick darkens, depositing a black substance containing carbon,
ness visible to the naked eye, while Bunge's, made of nitrogen, and perhaps hydrogen : ammonia is formed at
quartz crystal, I have not succeeded in seeing with the the same time, and many other products. Light favours
aid of a lens. I must admit that a fine edge would be this decomposition. Dilute solutions soon become turbid,
much less readily seen in a material like crystal than in but not always with the same degree of rapidity, some
metal, but it must also be admitted that the greater hard. samples resisting change for a great length of time, and
ness of the stone would give a permanence to the edge then suddenly solidifying to a brown pasty mass.
which a steel edge would not possess. Suppose we admit When hydrocyanic acid is mixed with concentrated
that in the crystal edges and planes the imperfections of mineral acids, as hydrochloric, the whole solidifies to a
a fulcrum are as nearly as possible eliminated--that the crystalline paste of ammonium chloride and hydrated
flexibility has been reduced to its smallest practical formic acid.
amount by the use of the girder form adopted by Bunge On the other hand, when dry ammonium formate is

- that the sensitiveness is under our command by screw- heated to 392° F., it is almost entirely converted into
ing up the centre of gravity, and that the quickness has hydrocyanic acid and water.
been obtained by reducing the length of the beam, where The experimenter may also produce, at any step, cy:
lies the practical limit to the smallness of the weight anides, cyanates ; cyanic and cyanuric acids; hydrated
which will turn the beam ? Mathematics would teach us cyanic acid, hydro-ferro and hydro-ferricyanic acids, or
that any weight, however small, would turn the beam to the combination of the same with bases. I might further
some extent, and that the limit is the limit of our vision. cite as an illustration of these remarkable changes, that
This points to the last particular in which Mr. Bunge has cyanic acid when mixed with water is decomposed almost
improved upon the old models. Having secured move immediately into acid carbonate of ammonium ; that pure
ment by the means already pointed out, he has magnified cyanic acid on standing soon changes spontaneously, with
the motion by increasing the length of his pointer, and a sudden elevation of temperature, into a solid, white,
this is of more importance than would at first sight appear, opaque, amorphous substance, called cyamelide. Further-
for it gives the principal advantages of a long beam with more, this curious body has the same composition as
out its failings, for the long pointer adds very little to cyanic acid, but is insoluble in water, alcohol, ether, and
the slowness of turning, and nothing to the flexibility. dilute acids; it is soluble in strong oil of vitriol by aid of

In making these remarks I would not have it supposed heat, with the evolution of carbonic acid and the producthat I am writing up the performances of Bunge's balance. tion of ammonia. When boiled with a solution of caustic I have simply endeavoured to understand and to explain alkali it dissolves with the disengagement of ammonia, by what principles the maker has obtained the very and a mixture of cyanate and cyanurate of the base geneexcellent results which we all admit.

rated. By dry distillation cyamelide is again converted
I must also add, that while I have connected Oertling's into cyanic acid.
name with a balance not equal to Bunges, I do not The artificial production of urea, a product of the
imply that Oertling's workmanship is inferior ; on the human body, from ammonium cyanate, marked a new era
contrary, requiring for the sake of comparison to experi- in organic chemistry, and constitutes one of Wöhler's
ment upon a beam of the form in general use, I preferred greatest discoveries.
to take one of Oertling's on the ground that his name Urea is decomposed, by the aid of heat, into cyanuric
was a guarantee of good quality.

acid and ammonia. Cyanuric acid is changed by a very
high temperature into cyanic acid. The study of cyanic
and cyanuric ethers, which were discovered by Wurtz, has

led to very important and curious results. A NEW METHOD FOR THE DETECTION OF

In this connection may be mentioned that curious body, COPPER, CADMIUM, AND BISMUTH.+ fulminic acid, which is isomeric with cyanic and cyanuric

acids ; also fulminuric acid, isomeric with cyanic, fulminic, By MALVERN W. ILES, Ph.'B.,

and cyanuric acids. In short, cyanogen and its compounds School of Mines, Columbia College.

are to me a perfect marvel! It is, I think, one of the

main keys to the intricate secrets of Nature, and when In working upon the cyanogen compounds, the experi. its behaviour is properly understood will unlock the door menter knows not what singular and unexpected results to various phenomena in organic chemistry now inexhe may bring about at every step. That his results are plicable. often very highly characteristic is well proven by the While working upon the ferro- and ferri.cyanides of beautiful shades of blue, green, red, white, yellow, and nickel and cobalt, with reference to a qualitative detection brown produced from this radical. Some of these tints of nickel in the presence of cobalt, I was led to study the are, however, very far from being beautiful; thus we have reađions of various other metals with the reagents a dirty, dark yellowish brown. Other shades may be above mentioned. Some of these reactions were described as brownish yellow, reddish brown, brownish striking that a qualitative separation immediately sug. grey, deep reddish brown, yellowish brown, orange-yellow, gested itself. For example. a solution of potassium ferriand various shades of white.

cyanide (I part salt to 38 parts water) yields with copper The deportment of various reagents with the cyanogen

a dirty yellowish brown precipitate, with bismuth a yelcompounds may give rise to products entirely nullifying lowish brown, and with cadmium a light yellow precipi; the experimenter's theoretical considerations, but fre- The copper and cadmium ferricyanides were found quently very highly characteristic of the element with

to dissolve entirely in potassium cyanide in slight excess, which he is experimenting.

while the bismuth separated in white floccules. Using As an illustration of the singular changes which cyano- this fact as a basis, my mode of procedure may be briefly gen compounds undergo, I may cite the following :

stated as follows:-Proceed with the H2S group up to the An aqueous solution of cyanogen rapidly decomposes, point where Cu, Cd, and Bi are obtained in solution toyielding ammonium oxalate, paracyanogen, a brown insogether, as usual, care being taken not to have too large luble matter, ard other products.

an excess of free acid ; then proceed with the following

scheme :* Mendeleef says in the ordinary arrangement of steel knife edges

Scheme for Cu, Cd, and Bi. upon agate bearings the wearing not only damages the stability of the balance but also quickly destroys its sensibility.

Add 6KCyFe-Cyo to slight excess; next add KCy and + A Paper read before the Chemical Section of the New York gently warm-the Cu and Čd are dissolved, while the Bi Academy of Sciences.--American Chemist.

remains as a hydrate ; filter.

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