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CHEMICAL NEWS,

Feb. 28, 1863.

Correspondence--Miscellaneous,

163. William Henry Harrison, Haverfordwest, "Improvements in covering wire and other iron articles for the purpose of protecting them from oxidation, and in the mode or method employed therein."-Petitions recorded January 19, 1863.

167. Joseph Mosheimer, Dolgelly, Merioneth, Wales, "Improvements in machinery for crushing and grinding quartz and other substances."

186. William Clark, Chancery Lane, London, "Improvements in desiccating and in preserving matters from decay."-A communication from Jean Baptiste Pierre Camille Bergouhnioux, Boulevart St. Martin, Paris.

2788. Richard Archibald Brooman, Fleet Street, London, "Improvements in refrigerating and freezing, and in apparatus employed therein.' A communication from D. J. Kennelly, Bombay. Petition recorded October 15,

1862.

3363. Rudolph Schomburg, Onslow Terrace, Lorrimore Road, and Adolph Baldamus, Surrey Terrace, Lorrimore Road, Surrey, "Improvements applicable to all kinds of oils used for illuminating purposes, whereby combustion thereof is rendered more perfect, smoke prevented, and the purity of the light increased." Petition recorded December 16, 1862.

89. Louis Henry Emmanuel Lepreux, Bordeaux, France, "Improved plates or slabs for preserving apartments from the effect of damp, and which are also applicable in the composition of plinths and foundations for walls." A communication from François Jaffary, St. Médard de Guizières, France. Petition recorded January 10, 1863.

171. Henri Adrien Bonneville, Rue du Mont Thabor, Paris, "Improvements in colouring, bronzing, and preserving iron and steel." A communication from Claude Joseph Thirault, Rue du Mont Thabor, Paris.

Notices to Proceed.

2842. James Spencer, Portsmouth, "Improvements in non-conducting compositions for preventing the radiation or transmission of heat or cold, and in coating metallic and other surfaces therewith."-Petition recorded October 22, 1862.

2903. Edward Scripps Tudor, Upper Thames Street, London, "Improvements in the purification of lead."

2906. Thomas Sutton, St. Brelade's Bay, Jersey, "Improvements in preparing albumenised paper for photographic purposes."-Petitions recorded October 28, 1862.

3418. Matthew Clark, Glasgow, Lanarkshire, N.B., "Improvements in treating waste liquors obtained when dyeing Turkey-red colours."-Petition recorded December 22, 1862.

3443. Ebenezer Stevens, Cheapside, London, "Improvements in machinery for preparing dough and paste suitable for making_bread, biscuits, pastry, cakes, and similar articles."--Petition recorded December 24, 1862.

133. George Graham, Dalquhoun, and John McLeod, Renton, Dumbartonshire, N. B., "Improvements in apparatus to be used in Turkey-red dyeing."-Petitions recorded January 15, 1863.

2698. James Newnam, Crayford, Kent, "Improvements in apparatus for crystallising and for evaporating." Petition recorded October 6, 1862.

2712. John Beale, Hope Street, Maidstone, Kent, and Mary Ann Beale, Upper Brunswick Terrace, Barnsbury, London, "Improvements in the preparation or manufacture of manure." Petitions recorded October 7, 1862.

2770. Richard Archibald Brooman, Fleet Street, London, "Improvements in apparatus for carburetting gas." A communication from Louis Bricout, Julien Bricout, and Emile Berlet, Reims, France. Petition recorded October 14, 1862.

2783. Pasquale Potenza, Naples, Italy, "The extrac. tion, preparation, and spinning of the silky fibre contained in the bark of mulberry trees, and the manufacture of the same intotextile fabrics."

CORRESPONDENCE.

Noad's Chemical Analysis.

To the Editor of the CHEMICAL NEWS.

107

SIR,-You have been kind enough to refer a correspondent to my work on "Chemical Manipulation and Analysis book has been long out of print, but I am now engaged on for a description of the chemical balance. This a new edition, the first part of which will soon be ready. I am, &c. HENRY M. NOAD. Chemical Laboratory, Medical School of St. George's Hospital.

Valuation of Chloride of Lime.

SIR,-As the import duties under the French tariff have enabled the soda manufacturers of this country to introduce bleaching-powder into France as an article of commerce, it has become desirable that the manufacturers should be in possession of ready means to convert the method of estimation adopted in France, with respect to this article, to that which is ordinarily used in this country; therefore, you may, perhaps, consider the following calculations and rules to be suitable for your valuable publication.

To the Editor of the CHEMICAL NEWS.

The system of chlorimetry arranged by Gay-Lussac, and adopted by the manufacturers and purchasers of bleaching-powder in France, is based upon the number of litres of chlorine gas, at mean temperature and pressure, which are contained in one kilogramme of the chloride

tested.

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The New Metal, Thallium.—As Englishmen, we naturally feel interested in that remarkable metal, since the honour of its discovery clearly belongs to a fellowcountryman. The question of priority of discovery has, however, been raised between Mr. Crookes and M. Lamy; it is one which, by reference to certain dates, admits of being satisfactorily disposed of. In cases of disputed discovery or invention, the dictum is often appealed to that "priority of publication constitutes priority of invention." This no doubt in many cases is a safe rule, but it is, never. theless, one under which, if invariably acted upon, much injustice might be committed. We believe that in deciding claims of priority, as other claims, all the evidence ought to be considered and receive its due weight. However, in the present case, according to the strict letter of the

108

Miscellaneous-Answers to Correspondents.

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rule adverted to, the priority of Mr. Crookes' claim may be firmly established. On March 30, 1861, Mr. Crookes announced in the CHEMICAL NEWS, "The Existence of a New Element, probably of the Sulphur Group." On May 18 of the same year, and in the same journal, "Further Remarks on the supposed New Metalloid' appeared. In January, 1862, Mr. Williams, as he has stated publicly in the CHEMICAL NEWS, saw the metal in Mr. Crookes' laboratory. Early in April of the same year, Messrs. Silverlock, the well-known printers of labels, printed, as can be shown by the books of that firm, labels of "Thallium," and many of its salts. On May 1, 1862, the International Exhibition opened; and there, in a case sent in some days previously, and open, of course, to public inspection and observation, and challenging the special attention of the jurors, was a specimen of the new metal, with the following explanatory labels attached :"Thallium, a new METALLIC Element,"-" Chemical Reactions of Thallium, by which it is distinguished from every other known Element; it appears to have the Characters of a HEAVY METAL," &c. Now this public exhibition of the metal, and the nature of which was so clearly expressed by the labels, cannot be regarded otherwise than as an act of publication on the broadest scale; and from it, even if no weight were allowed to the other acts and dates referred to, the discovery must be dated. Such, very briefly stated, is the evidence upon which the claim of our countryman rests. Let us now see what evidence can be advanced on behalf of the French claimant. M. Dumas, in his report on Thallium, states-"M. Lamy announced his discovery to the Société Impériale of Lille, on May 16, 1862; and on June 10 he submitted to the Jury of Chemists in London, in the presence of Mr. Crookes, a beautiful ingot of thallium." The case, then, stands thus:-On March 30, 1861, Mr. Crookes announced the existence of a new element; and on May 1, 1862, he exhibited at the International Exhibition the metal, accompanied by certain labels, showing that he was well acquainted with its metallic character and propertiesfacts of which he was cognisant, as proved by Mr. Williams and Messrs. Silverlock, at dates antecedent to May 1, 1862. On the other hand, the first announcement of thallium by M. Lamy did not take place until May 16, 1862, and it was not until June 10 that he exhibited the metal, and that under the name bestowed upon it by Mr. Crookes. It is true that Mr. Crookes' specimen was in the form of a black powder, as precipitated by means of zinc; while M. Lamy's sample was in that of a metallic button-a condition to which Mr. Crookes' specimen might have been brought by simple fusion under certain precautions. While desiring to do justice to Mr. Crookes in this matter, and to give honour where honour is due, we have no wish to disparage the services rendered to science by M. Lamy through his researches on thallium. We advise Mr. Crookes to submit the case to an impartial jury of savans for adjudication, although the result of such a proceeding does not appear to us to admit of a doubt.— Lancet.

SCHEMICAL NEWS,
Feb. 28, 1863.

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3. Tuesday. ROYAL INSTITUTION-Albemarle Street. 3 p.m. Professor Marshall," On Animal Mechanies." CIVIL ENGINEERS-25, Great George Street, Westminster. 8 p.m. PATHOLOGICAL-53, Berners Street. 8 p.m. PHOTOGRAPHIC-King's College, Strand. 8 p.m. ETHNOLOGICAL-4, St. Martin's Place. 8 p.m. 4. Wednesday. SOCIETY OF ARTS-John Street, Adelphi. 8 p.m. E. P. Alexander, "On the Sewing Machine: its History and Progress." GEOLOGICAL-Burlington House. 8 p.m. PHARMACEUTICAL-17, Bloomsbury Square. 8 p.m. ROYAL INSTITUTION-Albemarle Street. 5. Thursday. ROYAL-Burlington House. 8.30 p.m. Frankland," On Chemical Affinity." CHEMICAL-Burlington House.

3 p.m.

Dr.

J. B. Lawes,

8 p.m. F.R.S., "On the Assimilation of Nitrogen by Plants." ANTIQUARIES--Somerset House. 8.30 p.m. ROYAL SOCIETY CLUB-St. James's Hall. LINNEAN-Burlington House. 8 p.m. 6. Friday.

6 p.m.

8 p.m.

Dr.

ROYAL INSTITUTION-Albemarle Street.
W. A. Miller, "On the most Recent Spectrum Discoveries."
ARCHEOLOGICAL-26, Suffolk Street, Pall Mall East.
7. Saturday.

4 p.m.

ROYAL INSTITUTION-Albemarle Street.
3 p.m. Prof.
Max Müller, "On the Science of Language."

ANSWERS TO CORRESPONDENTS.

All Editorial Communications are to be addressed to the EDITOR, and Advertisements and Business Communications to the PUBLISHER, at the Office, 1, Wine Office Court, Fleet Street, London, E.C.

R. W.-Received. Answer as requested.

J. D.-Common glue will answer. Press well together.
S. P.-Add some dilute acid, and see whether effervescence takes

place; or add lime-water, and see if a cloudiness is produced,

C. W. Bingley-Received with thanks. We intend to go further

into the matter immediately,

A Subscriber.-The ignition is produced by the intense chemical action. If you use a dilute acid it will not occur.

S.-It is colourless iodide of starch. See CHEMICAL News, vol. iii., pp. 16-48.

Gas-Light Head-Dresses. A new feature in the application of gas to domestic purposes is said to be on the point of introduction. Fire-flies of gold and brilliants already sparkle upon the graceful white feathers and fresh green leaves that adorn the brows of some of our youthful queens. Clusters of diminutive gas-lights are now to spring from the elaborate tresses of beautiful matrons; the jets will issue from burners measuring a twentieth of an inch per hour, within transparent shades exquisitely cut, not larger than a cherry. The tubing is to be of solid gold, connected with a reservoir of the same valuable metal, which is to lie concealed in the meshes of luxuriant hair behind the head. The pressure will be applied to the Errata.-Last Number, page 92, four lines from bottom of first golden tank, which is supported by an elaborate back-column, for "thus," read "then;" and at the end of the sentence add, "and carbonic acid." Page 94, three lines from top of first column, comb, the top of which forms a row of little gas-lights. for “28,” read “23.”

G. F. Cusiter.-C, H2, or equal volumes of hydrogen and carbon. As a permanent gas. No determinations have yet been made that we are aware of, but we know of some in progress, which will be reported. The amount is, no doubt, very variable.

THE CHEMICAL NEWS.

VOL. VII. No. 174.-April 4, 1863.

SCIENTIFIC AND ANALYTICAL CHEMISTRY.

On the Decomposition of Chlorate of Potash at a Low Temperature, in Presence of Peroxide of Manganese, by M. E. WIEDerhold.

fore undertook the investigation of its derivatives, concerning which likewise our knowledge is very limited and contradictory. Thus, for instance, many chemists state that the alcohol obtained by the distillation of castor oil with potash is heptylic alcohol, whilst others regard it as octylic alcohol; and it is only by the most recent experiments of Bouist that we learn with cerdecom-tainty that this substance is octylic alcohol, inasmuch as he obtained the true heptylic alcohol by the action of nascent hydrogen on oenanthol. For the purpose of this investigation, I endeavoured to obtain the hydride this substance from the cannel oils is but small, and the of heptyl from the American petroleum, as the yield of labour of purification tedious and disagreeable.

THE author set himself to study the catalytic position of chlorate of potash in presence of oxides of manganese and copper. Contrary to M. Schönbein's hypothesis, he found that oxygenated bodies are not the only ones capable of determining this decomposition; for spongy platinum he found induced the same effect. An intimate mixture of two parts of chlorate of potash and one part of artificial peroxide of manganese begins to disengage oxygen between 200 and 205°; and this phenomenon takes place with the same proportions of chlorate mixed with oxide of copper at 230°; with platinum black, or natural peroxide of manganese at 260 to 270, and with peroxide of lead at 280-285°. The author believes that the action of these bodies is most likely due to their great power of absorbing heat, and in part also to the relative volume of the catalysing An interesting fact observed by him is the rising of the temperature of the mixture when the metallic bath wherein the retort is plunged reaches 250° for the mixture of chlorate and peroxide of manganese, and 290 for that of chlorate and oxide of copper.

substances.

In none of these decompositions is perchlorate of potash produced.-Poggendorff's Annalen der Physik

und Chemie, vol. cxvi., p. 171.

On the Chemical Constitution of American Rock Oil, by Mr. SCHORLEMMER, Assistant in the Laboratory of Owen's College.*

IN a paper published in the October number of the
Chemical Society's Journal, I showed that the products
of the distillation of cannel coal at a low temperature
contain a series of homologous hydrocarbons of the
formula CHR+2. I further showed that these are the
hydrides of the alcohol radicles, as upon treatment with
chlorine they yielded, by substitution of one atom of
hydrogen by one of chlorine, the corresponding chlo-
rides, from which other derivatives may be obtained.
In the portion of the oil boiling below 120° C., I
found the following four hydrides :—

C10H12 hydride of amyl, boiling point
C12H14 hydride of hexyl

CH hydride of heptyl
CHis hydride of octyl

16 18

39° C.

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68 C. 98° C. 119° C.

Of these the hydride of heptyl or oenanthyl is the most interesting, as it was previously unknown, and I there

Communicated by Professor Roscoe to the Manchester Literary and Philosophical Society.

The existence of this hydride in the petroleum was rendered probable by the fact of the discovery of hydride of hexyl by Pelouze and Cahours.

The oils which I examined are those known by the name of turpentine substitute, and obtained as the first products in the rectification of the crude oil. Different samples of the commercial articles possess very different properties; the specific gravity lies between 0.70-075. portion distilled over below 100° C., whilst others beOne sample began to boil at 30o C., and the greatest tween 80°-150° C., and others between 100°-200 C.

When these oils are subjected to fractional distillation, no product of constant boiling point is obtained, the oils requiring for this purpose a preliminary purification

with concentrated nitric acid.

The greatest portion of the oils remains unattacked, aniline was prepared), nitrotoluol, and binitrotoluol, and and the acid solution contains nitrobenzol (from which small quantities of fatty acids produced from traces of olefines which are probably contained in the crude oils.

I tried to separate these olefincs by adding bromine to the crude oil until the colour of the latter no longer disappeared; a few drops, however, are sufficient for a large quantity of the oil, and when the whole is subjected to distillation, a very few drops of bromine compounds of a high boiling point remained behind, the quantity of which was too small for further examination.

The oil after this treatment was well washed, dried over potash, and rectified repeatedly over sodium. By fractional distillation, the following four hydrides were obtained, and found to be identical with the hydrides

from the cannel tar :

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158

On Some Reactions of Subformiate of Ethyl.

of amyl boils at 39° C. The same compound from petroleum boils at 34° C. I find, however, that the presence of traces of foreign substances alter the boiling point of this body very considerably. Thus, for instance, I obtained from the crude oil about one ounce of a liquid which boiled from 15°-20o C.; after treatment with nitric acid, the volume of the liquid remained almost unchanged, showing that only a very small quantity of substance had been removed; but, after drying with potash and rectifying over sodium, it was found that a mere trace of the liquid boiled below 30° C.; nearly the whole distilled at 34° C., and consisted of hydride of amyl. Of the four hydrides which I isolated, I have only prepared the hydride of heptyl in quantity; four gallons of turpentine substitute boiling between 80°-150° C., yielded three pounds of the pure compound. In order to obtain from this other heptyl compounds, it was transformed into the chloride according to the excellent method described by Hugo Müller, which consists in the addition of a small quantity of iodine to the substance which is to be treated with chlorine. The substitution occurs much more rapidly in this case than when chlorine alone is employed, and goes on in absence of the daylight, so that a rapid current of chlorine gas can be led into the liquid without any chlorine escaping with the hydrochloric acid vapours.

Hence it is seen that the constitution of American petroleum, at least that portion boiling below 120° C., is quite analogous to that of the oil from cannel tar.

Petroleum consists mainly of the hydrides of the alcohol radicles; it contains very small quantities of benzol and toluol, and probably traces of olefines; whilst in the cannel coal oil the hydrides are found in smaller quantities, and benzol and toluol in proportionally larger amounts. In the oil obtained by distillation of boghead coal, Greville Williams has discovered a series of hydrocarbons possessing the composition and physical characters of the hydrides CnH2+2, also benzol and its homologues and olefines.||

The rock oils obtained in other countries appear to possess a somewhat similar constitution.

Thus, for instance, Warren de la Rue and Hugo Müller found in the Rangoon tar, benzol, toluol, xylol, and cumol and hydrocarbons of the formula CnH2+2. They were, however, unable to isolate from these a compound of definite composition and boiling point. The rock oil from Sehnde, in Hanover, consists, according to the investigation of Busenius, Eisenstuck, and Uellsmann,†† of hydrocarbons of the same general formula, but they likewise failed to obtain definite products. Pebal and Freund‡‡ found in the rock oil from Gallicia benzol and homologues, carbolic acid and homologues, and hydrocarbons which are not attacked by the strongest acids, and probably identical with those previously mentioned.

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CHEMICAL NEWS,
April 4, 1863.

It is better to use quartz than bichromate of potash, because the mass calcines without melting, and there is no fear of its projecting pieces of the mass. The presence of chlorides and sulphates is no inconvenience; nitrates only are decomposed. Amorphous and crystallised silica behave in almost exactly the same way. Silica may be replaced by bichromate of potash in the estimation of carbonic acid; to expel all the carbonic acid a higher temperature is necessary than that required for the decomposition of nitrates; however, the red heat produced by Bunsen's simple gas jet is sufficient.Poggendorff's Annalen der Physik und Chemie, vol. cxvi., p. 635.

On Some Reactions of Subformiate of Ethyl,
by H. BASSETT, Esq.

THE formation of this substance, described by Kay and
Williamson, from ethylate of soda and chloroform, the
chloride of a triatomic radical, suggested the possibility
of regarding it as a derivative of the glycerine of the
mono-carbon series, the three equivalents of hydrogen
being replaced by three of ethyl, and the following
experiments were made in pursuance of this idea:-

In the first place, it was advisable to find a process for its easy preparation, as those recommended by Kay are troublesome, and, moreover, produce only a small quantity. The following method gave a product nearly equal in bulk to the chloroform used:

Eighteen ozs. absolute alcohol, and 3 ozs. chloroform introduced into a flask furnished with an upright condenser-1 oz. sodium then added by small portions, the action being assisted by a gentle heat in the waterbath. The alcohol then distilled off in the water-bath, the residue dissolved in water, and the supernatant oil dried with chloride of calcium and rectified.

Three equivalents of the substance thus obtained were heated with two equivalents of boric anhydride in a sealed tube for six hours at 100°. The resulting solution heated in a retort up to 200°. The distillate agitated with a small quantity of water, when an ethereal layer floats on the top, in which can be distinctly recognised the odours of ordinary ether and formic ether; the boiling point (35° to 55°) also indicates such a mixture. In a solution of this in a larger quantity of water formic acid is easily detected by chloride of mercury and sesquichloride of iron. The residue in the retort presents all the characters of biborate of ethyl; is decomposed violently by hot water with evolution of vapours of alcohol."

The reaction may be written:-†
3(C,H6O3)+2B0,= (CH),B,O,+2C.H

16

C2H

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This formation of boric ether appears to confirm the formula given by Ebelman similar to that of anhydrous borax.

similar results, only one equivalent of the anhydride The action of acetic anhydride in excess, at 150°, gave entering into the reaction.

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O=CT} 0+2

C2H2O
CH

Acted on two equivalents of the substance with one equivalent ter-iodide of phosphorus, and the result distilled, a thick, very acid liquid remained in the retort, * Procee lings Royal Society, June, 1854.

† C = 12 0 = 16.

1

CHEMICAL NEWS, April 4, 1863.

On the Assay of Alkaloids.

presenting the characters of ethyl-phosphorous acid. The distillate was digested with an excess of dry phosphate of silver to separate the iodide of ethyl. On distillation in the water bath a volatile inflammable liquid came over, soluble in a large quantity of water, having the peculiar smell of formic ether-boiling-point 52° to 56°. In its watery solution formic acid could be readily detected. The reaction may be represented as follows, the water arising probably from moisture in the iodine :2(C,H1603) + PI3+H2O=(C2H¿)H2PO3 + зC2H2I+

CHO

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These experiments tend to show that the compound in question functions as a true tribasic formic ether, similar in composition to the best defined metallic subsalts of the fatty acids.

Analytical Notices on Uranium, by M. H. Rose. OXIDE of uranium may be completely precipitated from its acid solutions, having previously saturated them with ammonia, by addition of hydrosulphate of ammonia. No inconvenience results from the solution containing many ammoniacal salts, excepting, of course, carbonate of ammonia and all alkaline carbonates. The precipitate is black, or reddish brown if the hydrosulphate be greatly in excess. It is washed in water, to which is added a small quantity of hydrosulphate of ammonia. The precipitate is formed essentially of protoxide of uraniam, and contains no sulphide of uranium. After being dried, it is ignited, to expel what little sulphur may be retained; then it is calcined in a hydrogen current, at a high temperature, and left to cool in the hydrogen. Pure protoxide is thus obtained. Should the solution contain much salts of potash, or of other strong non-volatile bases, the precipitate will retain a small quantity of these bases.

Oxide of uranium is separable in the following manner from most metals, especially from those which are completely precipitated from their solutions by hydrosulphate of ammonia :-Add to the solution excess of carbonate of ammonia mixed with hydrosulphate. All the oxides which hydrosulphate transforms into sulphides are precipitated, while the protoxide of uranium is dissolved in the carbonate of ammonia. Leave the mixture to deposit in a closed vessel, wash the precipitate by decantation, with water containing carbonate and hydrosulphate of ammonia, and then filter. Gently heat the filtered liquid, to expel most of the carbonate; decompose the hydrosulphate with hydrochloric acid; oxidize the protoxide of uranium by nitric acid, and precipitate the oxide by ammonia, and, before weighing, calcine it in a hydrogen current.-Poggendorff's Annalen der Physik und Chemie, vol. cxvi., p. 352.

PHARMACY, TOXICOLOGY, &c.

On the Assay of Alkaloids-Pure and in Preparations, by FERDINAND F. MAYER.

IN a paper laid before the last meeting of the American, Pharmaceutical Association (August, 1862), I pointed out the facility with which the iodohydrargyrate of potassium could be used for the quantitative determination of all vegetable alkaloids, either pure or contained in pharmaceutical preparations.

This test, which was first described by F. L. Winckler,

159

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base with iodide of mercury; in consequence of which a The compounds formed are the hydriodates of the part of the mercury used for precipitation remains in solution. For this reason a solution of chloride, and not of iodide of mercury must be used, inasmuch as with a solution of the latter the results very much differ;

nor must the solution of alkaloid be added to the mercuric tates form in acid, neutral, and slightly alkaline solusolution, but the latter to the former. These precipitions, and, as Nessler noticed,‡ permit the separation of

the bases from ammonia.

They are further not interfered with by the usual constituents of pharmaceutical preparations, except alcohol and acetic acid, in both of which the precipitates are soluble. In this the iodohydrargyrates and Groves'§ bromohydrargyrates differ from all other precipitants of the alkaloids, which as a rule do not allow of the presence of starch, gum, albumen, or tannic acids.

As to the intensity of the reaction, it falls in some cases short of that produced by phosphomolybdic acid, while in others it far exceeds it.

Distinct reactions are obtained with iodohydrargyrate of potassium in solutions, containing—

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more distinct when a certain measure or bulk of solution has been prepared from the extract or mixture by means of dialysis through parchment-paper.

But where no colouring matter, or substances affecting nitrate of silver are present, the excess of iodohydrargyrate and of iodine and chlorine may at once be

"Buchner's Repertorium," vol. xxxv. p. 57. On some Precipitates caused by solutions of Hydrochlorate of Quinia and by Iodide of Mercury.

"Das Verhalten der Alkaloide gegen Reagentien." Heidelberg,

bei J. C. Mohr., 1846.

t "Verhalten des Jodquecksilbers zu Ammoniak und eine neue Reaction auf Ammoniak. Inaugural Dissertation," Freiburg, 1856. Also, Chemisches Centralblatt, 1856. No. 34-Jahresbericht der Chemie

for 1856.

§ Quarterly Journal of the Chemical Society, vol. xi. p. 97. Pharm. Journal and Trans., vol. xviii. p. 131. Jahresbericht der Chemie for 1858,

100

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