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New Induction Balance. June 6, 1879.

247 riment was made, with a view of ascertaining whether the , obtained for each motion. An ingenious adjustment by circuits could be increased in length to a considerable means of a movable nut allows the phase of either or both degree without diminishing the apparent value of the motions to be altered to a known extent, and thus an lights on such circuits. The Westminster and Waterloo endless variety of figures can be obtained. As in other circuits—that is to say, the two at each end of the line- harmonographs, a writing table, on which the paper is were thrown into one, the total length of wire being placed, and an aniline glass pen, are used. Several of 7063 feet, three of the lights being at the Westminster the figures done also on glass were thrown on the screen, end and the other two at the Waterloo end. The lights the stereoscopic effect being very apparent. In reply to burned with apparently equal brilliancy as when short- a query, Mr. Wilson said that he had adapted some of the circuited, and on the following day the length of the line figures to the stereoscope. was increased to 8815 feet, or 1.66 mile, but still without Prof. Hughes explained his new Induction Balance, any perceptible effect on the light. We believe this is the and showed some of its principal effects. It is well known longest circuit ever attempted to be used with an alter that on an electric current passing along a wire adjacent nating current machine, and the success of the experiment to another wire, an induced current is set up in the second has a very important bearing on the general question of wire in an opposite direction to the first or primary electric lighting.

current. In the induction balance two primary circuits or We have said before that the cost of a plant necessary coils are taken, with the same current (interrupted by a for working twenty Jablochkoff lights is £990. The in- microphone acted upon by the ticking of a clock) running terest on this at 5 per cent would be £49 10s., and taking through both; and between these is placed a secondary wear and tear at 10 per cent, £99, we get a total of circuit or coil in connection with a telephone. The £148 1os. Taking the whole time during which the primary coils are so wound as to oppose each others lamps are lighied in the year at 3600 hours, say 10 hours induction on the intermediate secondary. There is a a day, the cost of use of plant for each light per hour is point, moreover, between where these opposed in. 0:49d. To this we must add 3:24d. per light per hour for ductive influences exactly neutralise each other. If the the cost of producing the light, and 2d. per hour per secondary coil be placed there, no induced ticking of the candle, making a total of 5'73d. per light per hour all the clock can be heard; but if the secondary be displaced to year round. Let us now compare the cost of gas with one or other side of this point, the ticking can be heard ihe latter figure. The light in the opal globe, as given in the telephone, increasing in loudness as the secondary above, is in round numbers equal to 155 candles, and in approaches one or other of the primaries. If the distance the granulated globe to 265 candles. To produce a light between the primaries be graduated into a scale, this equal to 125 candles, one of the larger Sugg burners con- contrivance becomes a sonometer, since it gives an sumes 48 cubic feet of gas per hour, while to produce a absolute zero of sound and degrees of loudness. It is 265-candle light we should require 83 cubic feet per hour. well adapted for measuring the hearing power of the ear, The cost of the former quantity of gas may be taken at 2d., and when used for this purpose it is known as the audiometer. of the latter at 3.5d., or, to put the matter more plainly ,- By splitting the secondary coil into two parts and placing The cost of the electric light is .. 5:73 per hour.

each close to its proper primary, so that there are four Gas equivalent to electric light in

coils in all arranged in two pairs, the extremes in one opal globe

primary circuit and the means in one secondary, the two Ditto ditto, frosted globe. :

opposing parts of the balance can be separated from each 3:50

other, so as not to disturb each others action, and the We have therefore, at last, a series of figures on this balance made very sensitive by the closeness of the important subject which cannot possibly be doubted. The primaries and secondaries. Prof. Hughes finds that there experiments which have yielded them have been carried is a line or zone of maximum induction midway between out with the greatest care, and every precaution has been each primary and its secondary. If a conductor, such as taken to render them so correct that all future cavil or a piece of metal, be put in this position it has a maximum controversy will be avoided; the practical outcome of the distributing effect on the balance, due probably to the matter being that, used in the best possible manner,

th electric currents generated in it by the induction. The amount of illumination in both cases being equal, the effect is apparently proportional to the conductivity of the electric light costs If times as much as gas.

metal. It requires an exactly similar piece of metal put between the other pair of coils to restore the equilibrium of the balance. A very slight difference of alloy or of weight

between two like coins is at once observed from the im. PROCEEDINGS OF SOCIETIES. perfect restitution of the balance ; base coins are thus also

at once detected. Again, it is possible for a person to

tell what particular coin or coins are in one part of the PHYSICAL SOCIETY.

balance by trial of the same coins in his part. When Ordinary Meeting, May 24, 1879.

plates of non-magnetic metals are held vertical in the balance their distributing effect is nil; iron, on the other

hand, gives its maximum effect at this position, because Prof. . G. ADAMS, President, in the Chair.

its maximum effect overbalances its electrical effect. Two

pieces of iron may therefore neutralise each other as cores New members :- Mr. R. Sedley Taylor, M.A., and Mr. in an induction coil. Steel is easy to balance comWalter Emmott, A.S.T.E.

pared with soft iron. Zinc disturbs most when placed Mr. W. J. Wilson exhibited a new harmonograph and along the sides of each pair of coils; iron when in centre. figures drawn by it. The figures drawn by prior harmono- A certain length of metal laid along the outsides of the graphs are all 'more or less imperfect, owing to loss of coils produces silence. The maximum line of inductive motion in the pendulums actuating the marking pen ; and force is midway between the coils, and there is a line of Mr. Wilson therefore designed a new harmonograph, minimum force at half the thickness of each coil; a metal which not only gives perfect figures, but admits of the placed at these lines of minimum force has no disturbing phase of either of the two compounded motions being effect on the balance. Pressure, torsion, heat, magnetism, decreased by a known amount. In this instrument toothed | strain, and in fact all imponderable forces, are indicated, wheels take the place of pendulums, the ratio of the and their effects may be measured. teeth giving the ratio of the periods of the motions. By Prof. W. G. Adams believed that one result of Prof. employing the device of an intermediate wheel gearing | Hughes experiments will be the determination of the way with two others, and arranging two or more wheels on in which the law of electro-dynamic induction depends he intermediate axle, a great variety of phase can be on density. He also imagined that the metal when in

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248
Report on the Air of Glasgow.

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June 6, 1879. the maximum line between the coils gathered the lines of chemists, more remote. Besides this, the difficulty of force to itself, whereas when on the minimum lines it hunting down a practical fact amongst a crowd of theories could not thus divert them.

is avoided. Prof. Ayrton cited the early experiment of Faraday In the present issue the author has adhered more or with a sheet of copper oscillating to rest between two less closely to the lines followed in the first edition, which opposite magnetic poles. The copper took a long time was published in 1874. As then, he divides the elements to stop; but a sheet of iron placed between two like and pseudo-elements into monads, dyads, &c.—an ar. poles was soon stopped, owing to its becoming imbued rangement which greatly helps the memory. The chapter with an opposite polarity, and deflecting the lines of force. on Chemical Theory has also undergone the process of He also suggested that the divergence of the results for subdivision, and the matter has been greatly extended. conductivity of metals got by the induction balance from The chapters on the Organic Compounds have also rethose got by the Wheatstone balance might be due to ceived large additions, and have also been relegated to the that electric inertia suspected by Sir William Thoinson. concluding chapters of the book instead of being classi

Prof. Guthrie thought that the induction balance fied according to their chemical constitution as in the first pointed to the conclusion that the disturbing effect of a edition. This arrangement, though perhaps not very phiconducing mass applied in this way is proportional to losophical, is at any rate a convenient one for the hard the quantity of electricity generated in it under certain worked medical or pharmaceutical student. conditions of temperature, &c. The determination of the Two useful appendices have been added to the new conductivity of liquids would be a useful application of edition: one showing the quantities of the various ingrethe balance.

dients to be added in parts by weight to 100 parts of Mr. CHANDLER Roberts gave some results which he alcohol, to produce the different artificial fruit essences; had obtained from an examination of certain alloys by the other, the relation between the density and flashing means of the induction balance. He had been able to point of paraffin oils. These appendices will be of great detect a difference of i part in 1000 in the amount of use to the practical chemist, but why annex them to the silver present in two shillings of equal weight. He theoretical division of the work ? also pointed out that Mathiessen divided alloys into The second volume of the work has been in a great three classes :-(1) Solidified solutions of one metal measure remodelled and re-written. The processes emin another; (2) Solidified solutions of one metal in an ployed by chemists are first described, beginning with allotropic modification of another metal; (3) Solidified solution and lixiviation, and ending with electrolysis and solutions of allotropic modifications of both metals. pyrology. The next chapter treats of the detection and For the first class the curve of electric conductivity is a separation of the metals used in pharmacy, and Chapter 3 straight line; for the second, a parabolic curve; for the third, follows with the detection and separation of the acidulous a bent line. Mr. Roberts found that the balance gave radicals. Chapter 4 gives the method of quantitative the characteristic curve for the first class with an alloy of analysis as applied to the examination of the official salts lead and tin, and for the second with an alloy of gold and official, by the way, being the new and more correct silver. With a copper-tin alloy, which is a good epithet applied to what used to be called officinal preparaexample of the third class, he found the curve given by tions. The next chapter gives a course of quantitative the balance to be intermediate between Alfred Rich's analysis as applied to the detection of unknown salts, curve of density and Matthiessen's curve of conductivity, while Chapter 6 gives a complete course of alkaloidal and considers that the balance is influenced by the density analysis. The other chapters are devoted to toxicological as well as by the conductivity of the metal interposed.

analysis, volumetric and geometric quantitative analysis Prof. Hughes said that as the working of metals ap- in general, ultimate organic analysis, and, lastly, special peared to effect their conductivity, he was inclined to rely analytical processes, such as the analysis of potable more on the conductivity measurements of the balance water and cinchona bark, the valuation of opium, the than on those of the Wheatstone bridge. By the balance estimation of emetine in ipecacuanha, the alcoholic plain pieces of metal were taken, whereas by the bridge strength of spirits, wines, and tinctures, and the analyses wires were mostly taken. He would rather not give ary of urine and urinary calculi. theories yet as to the results obtained from the balance. Mr. Joseph Ince has again done good service to Dr.

Dr. Erck then exhibited his novel Pump for lifting Muter by undertaking the tedious-but, as far as his stuBulutions out of batteries.

dents go, certainly not the thankless-task of compiling copious indexes to both volumes, which will greatly add

to the value of Dr. Muter's already valuable work. NOTICES OF BOOKS.

Report on the Air of Glasgow, chiefly relative to Enclosed

Spaces and Smoke. By W. J. DUNNACHIE, in coAn Introduction to Pharmaceutical and Medical Chemistry

operation with the Medical Officer of Health. Pre(Theoretical and Descriptive), arranged on the principle

sented to the Committee of Health of the Magistrates

and Council of Glasgow. May, 1879. of the Course of Lectures as delivered at the South London School of Pharmacy. Second Edition. By It is found that the proportion of atmospheric sulphur Dr. John Muter, M.A., F.C.S., &c. London : Simpkin reaches its annual minimum in July, and, as might be and Marshall. 1879.

expected, is highest in the central stations. Nitrogen, in An Introduction to Analytical Chemistry, &c. Second has two periods of excess, one in the summer and one in

the forms of actual and potential (albuminoid, ammonia, Edition. By Dr. JOHN Muter, M.A., F.C.S., &c. London: Simpkin and Marshall. 1879.

the winter. It appears, from Mr. Dunnachie's experi.

ments, that these two forms of ammonia are largely derived Dr. Murer has done well to divide the second edition of from the combustion of coal, &c., and are consequently his “ Pharmaceutical and Medical Chemistry" into two no absolute indices of the sanitary condition of the air

. separate volumes. The first part, being almost purely This fact has scarcely received sufficient attention on the theoretical in its character, is intended to be for perusal at part of sanitary chemists. Even Dr. R. A. Smith, in his home, while the second half, being purely pradical, is to classical work on “ Air and Rain,” though fully admitting be used in the laboratory. Besides obviating the incon- the presence of tarry distillates in the atmosphere, still venience of dragging a heavy book backwards and for says " the ammonia is one measure of sewage of air not wards from the study to the laboratory, the division of the purified.” Dr. J. B. Russell observes that the methods Manual into two parts will render the possibility of spoils of Pasteur and Pouchet, of Cohn and Lister, are necesing an expensive work, by the accidents common to all sary to give precise meaning to the work of Angus Smith

CHEMICAL News,}
Method of Determining Glucose:

249 and other chemists in the region of air, and of Wanklyn / that I received a private letter from the Secretary, Dr. and Frankland in the region of water.” The guidance of Ferguson, of Edinburgh, which I still have, in England), chemical analysis is not absolute and all-sufficient; but in which my prior claims were fully acknowledged, and I as the most dangerous impurities, whether of air or of was informed, too, that my report or letter to the Glasgow water, appear to be not merely organic, but organised, it Herald was framed as the first. Dr. Macadam was men. must be controlled and supplemented by biological inquiry. tioned, too, as having been the first to invite a scientific This, however, neither Dr. Angus Smith nor Prof. Frank. investigation to the theory I brought forward, and so to land will, we think, dispute.

support it further. Still, I must conscientiously acknowledge that the brain which to the best of my knowledge

deserves the fullest credit of the conception is that of the Proposed Legislation on the Adulteration of Food and Austrian chemist, whose name I have forgotten, but whose

Medicine. By E. R. SQUIBB, of Brooklyn. New York: little notice in Dingler's Journal supplied me with the neces. G. B. Putnam's Sons.

sary light on the snbject, which I did but endeavour to This pamphlet comprises the draft of an anti-adulteration spread and throw upon that fatal catastrophe at Glasgow. law for the State of New York. It includes definitions of Mr. M.Dougallis leiter will be welcomed as a very inte. food, of medicine, and of the offence of adulteration, the resting contribution, and I feel no doubt he is right as to various phases of which are illustrated by examples. The the abolition of the stive-room. With regard to the inpenalty for a first offence is a fine not exceeding two

convenience of small electric lights disposed over a flour. hundred dollars, and for further convictions imprisonment mills, I cannot judge, not having experience in the with hard labour for a term not exceeding six months.

matter. It is for the mill-owner to decide which inconThe Act is to be worked by a State Board, composed of venience is greater, that of ordinary lights, with the two physicians, one chemist and physicist, one lawyer, chance of explosions; or the electric lights, with safety. and one“ business man."

I fancy the filtration of the air, as Mr. M.Dougall sug. The author gives an abstract of English legislation on

gests, may prove a difficult matter; but I wish it all the adulteration question, and a history of their working success, as it would doubtless remove the danger. Still

, Here he speaks of analysts who took the initiative, it is always to be remembered that from abnormal causes bought their own samples for analysis, and entered upon laden with four dust in certain rooms or parts of the mil

!

and accidents, the air may sometimes even then become prosecution where necessary." This is a misapprehension. A public analyst who should act in this manner

and a vivid flash might communicate itself where an ordiwould be gravely overstepping his duty.

nary flame or light would fail to do so.-I am, &c.,

Watson Smith, F.C.S., F.I.C. Zürich, June 1, 1879.

CORRESPONDENCE.

DR. PAVY'S METHOD OF DETERMINING

GLUCOSE.

MANUFACTURE OF SULPHURIC ACID.

To the Editor of the Chemical News.

SIR,–It was only a few days ago that my attention was To the Editor of the Chemical News.

drawn to the article by Mr. Otto Hehner in the CHEMICAL Sir,-I was pleased to note in the Chemical News, News (vol. xxxix., p. 197) on the ammoniated cupric liquid vol. xxxix., p. 226, only just to hand, that Dr. Lunge proposed by me for the quantitative determination of sugar. qualifies the favourable opinion on the use of liquid nitric I am glad to find that 'so able a chemist as Mr. Hehner acid, given on his authority in Lock's work, lately has conducted an inquiry into the merits of the test, and published, on the manufacture of sulphuric acid; for, í it is satisfactory to notice that with a proviso regarding confess, I was somewhat surprised on reading the book, the amount of alkali employed he is able to speak of the to find that, with his extended practical experience, he method as “capable of furnishing excellent results.". should advocate a process which entails expenses in the At the outset of his investigations Mr. Hehner obtained shape of labour, fuel, and maintenance of extra plant, as results which stood at variance with mine, and considerwell as unavoidable loss and waste. After undertaking ately paid a visit to my laboratory at Guy's Hospital to the management of these works I seized the first oppor. see in what manner the discordancy was to be accounted tunity of setting up two large Daglish's nitre pots, and for. Upon being informed of his mode of procedure, to discard the nitric acid stills. The result is a saving of which consisted in using 100 c.c. of the test-liquid, and It per cent of saltpetre on the 100 tons pyrites burnt dropping the saccharine solution in slowly throughout the weekly. The requisite quantity of nitre is weighed out process, instead of employing only 20 or 40 c.c., and iwice daily to the chamber foreman, and is proportion- running the liquid in rapidly from the burette until near ately charged into the pots once every hour.-I am, &c., the point required, and then proceeding slowly-a differ

JOHN Cox. ence which leads to the operation being much more pro.. Chemische Fabrik "Colombia,"

longed in the one case than in the other, it immediately Mülheim-a-Rhein, May 26, 1879.

occurred to me that the discordarcy arose from the test. liquid failing to resist the influence of the prolonged boil

ing, and that this would probably be rectified by the emEXPLOSIONS IN FLOUR-MILLS.

ployment of a larger amount of alkali. I have found with

Fehling's solution that its stability under ebullition is To the Editor of the Chemical News.

impaired by dilution unless an additional quantity of alkali SIR,Will you allow me, in reply to Mr. Arthur M.Dou- is put into it. I suggested to my assistant, Mr. Scard, gall's letter, briefly to state that my letter on the above who has ably worked under my direction in this matter, subject appeared in the Glasgow Herald immediately that more alkali should be used, and it was found that the after the explosion in the Tradeston Flour Mills; in fact, true explanation of the discordancy had been hit upon. I believe, about a couple of days after the sad accident. Without further concert than I have mentioned, the idea It was noticed in a brief leading article on the subject as also occurred to Mr. Hehner to try the effect of a larger the most likely solution of the mystery, and afier Dr. quantity of alkali, and when an interview took place a Stephenson Macadam's paper appeared (which was con- short time afterwards each learnt that an accord had been siderably afterwards), the Scottish Royal Society ap- arrived at. pointed a commission of inquiry into the subject, together In my communication to the Royal Society I stated with the question of priority, the upshot of which was that with the test proposed, i atom of sugar appropriated

CAEMICAL News, 250 Chemical Notices from Foreign Sources.

June 6, 1879. 6 atoms of oxide of copper instead of 5 as is the case with to give this as the relation existing. I am not aware that Fehling's solution used in the ordinary way. I further the extent of reducing action of uric acid upon the oxide mentioned that potash might be added to the extent of of copper has hitherto received attention, and I should I grm. to 20 c.c. of the ammoniated test without altering be glad to learn if the conclusion I have mentioned is the result, but that with the addition of 5 grms., or any- | confirmed by the observations of others.--I am, &c., thing beyond, 5 instead of 6 atoms of oxide of copper were

F. W. PAVY. appropriated by i atom of sugar, and with quantities of May 30, 1879. added potash between the 1 and 5 grms, the results stood between the 5 and 6 atoms of oxide of copper. Mr. Hehner, in commenting upon this, says that his observations, which he has verified over and over again, show that a much CHEMICAL NOTICES FROM FOREIGN smaller excess of soda influences the result than is stated by me. Mr. Hehner seems not to have noticed that the

SOURCES. added alkali in my observations consisted of potash instead of soda, which he employed. The difference in the atomic weights of the two alkalies will nearly suffice to

Note.-All degrees of temperature are Centigrade, unless otherwise

expressed. account for the difference existing in our recorded results.

For many years past the liquid which has been used in my laboratory as a sugar-test has been made with potash Comptes Rendus Hebdomadaires des Séances, l'Académie de instead of soda, and has contained nearly double the

des Sciences. No. 17, April 28, 1879. equivalent of the soda existing in Fehling's solution. I The Electric Light.-J. Jamin.--The burner sub. was led to introduce the larger amount of alkali because mitted to the Academy with its points downwards has it appeared to me that the liquid possessed greater sta. considerable advantages; such as simplicity, since it rebility and precision of b haviour. I am now using this quires no mechanism and stquires no preliminary preliquid not only as formerly, but also for the preparation of paration, beyond a support and the coke points; mecha. the ammoniated solution, and it contains a sufficient nical economy, since the number of flames is almost amount of alkali to serve for what is required. The quan- doubled ; augmentation of light, since each of the new tity of copper is the same as in Fehling's solution. The foci is almost twice as powerful as those of the old contwo liquids therefore possess the same quantitative value. struction ; quality of the light, which is whiter; more The composition is as follows :

advantageous arrangement of the foci, which direct their Cupric sulphate..

34:65 grms.

greatest quantity of light downwards, where it is wanted, Potassio-sodic tartrate (Rochelle

instead of up into the air, where it is useless; and, lastly, salt)..

173

economy of combustible material. Potash

160

Electric Inscription of Words.-M. Boudet de Paris. Water to 1 litre.

- The transmitting apparatus is a microphonic speaker,

the carbons of which, instead of being pressed by a spring, For the ammoniated test 120 c.c, of this solution are

are simply maintained in contact by the pressure of a mixed with 300 c.c. of strong ammonia (sp. gr. 0:880), and small piece of paper folded in form of a V. The vibra. water is added so as to make up to a litre. The test, tions of the diaphragm of the receiving apparatus cannot being in this form a 6-atom instead of a 5-atom oxidising be written, since the movements of the style, however liquid, it is of 1-10th the value in relation to sugar indi delicate the apparatus, can scarcely be distinguished upon cation of the original solution, or 20 c.c. correspond with the lamp-black. To enlarge the magnetic vibrations of 0.010 grm. of glucose.

the receiver the cover and the diaphragm of a Bell's On account of the liability of the cupric sulphate to telephone are taken away, and on the wood of the in; impurity it is preferable, where great accuracy is required, strument there is fixed the end of a small stiff steel to use electrotype copper.. The quantity of copper to be spring. The other end of the spring abuts on the surface taken is 8.808 grms." This is dissolved in nitric acid and of the magnetic nucleus surrounded by its coil; to this evaporated to dryness after the addition of sufficient sul., extremity is soldered a small mass of soft iron, weighing phuric acid to secure that a sulphate is left. The product about 10 grms., and upon this mass and in the produced is then dissolved in water and neutralised with potash. line of the axis of the spring is fixed a light style of In this way the exact amount of cupric sulphate is supplied bamboo, 10 centimetres in length and terminating in a that is required to yield a solution of the standard strength. slender whale-bone pen.

I originally recommended, for preventing the atmosphere from becoming charged with the evolved ammonia; following Definition of Temperature; the Tempera.

Theoretic and Experimental Demonstration of the that a U-shaped tube containing fragments of moistened pumice-stone should be used. I find that a much more

ture is Represented by the Length of the Calorific simple and convenient contrivance for attaining the object A mathematical paper, not capable of useful abstraction.

Oscillation of the Molecules of a Body.-R. Pidet.is aiforded by carrying a piece of vulcanised tubing from the flask into a beaker or other vessel containing water.

A Siren with an Electro-magnetic Regulator.-M. The end of the vulcanised tubing intended to dip into the Bourbouze.-By means of this instrument sound can be water is plugged at the extremity, and just above the plug made to pass from 8162 vibrations per second, through provided with a transverse slit through three-fourths of all the intermediary notes to 128 vibrations. its extent. This admits of the escape of air and ammo- The Laws of Dissociation.-MM. Moitessier and R. niacal vapour from the flask, but precludes by its valvular Engel.—The dissociation of a body both whose comarrangement the sucking back of water from the occurrence ponents are volatile takes place even when the body is of any sudden condensation in the interior of the Alask.

placed in presence of one of the products of dissociation, Uric acid exerts a reducing action upon oxide of copper so long as the tension of this product does not surpass equally as precise as glucose. The quantitative deter- the dissociation-tension of the body at the temperature of mination of it has hitherto constituted a lengthy and not the operation. When the tension of one of the comvery satisfactory process, but I find that with the ammo- ponents is greater than the dissociation-tension of the niated cupric líquid its determination may be easily and compound the dissociation no longer takes place. Two speedily effected. A large number of observations have cases may then arise; either the dissociable compound is been conducted in my laboratory with the view of ascer- volatile, and in that case the true vapour density may be aining its precise reducing capacity, and the results so determined, or else the dissociable body is not volatile, closely conform with the expression that 3 atoms of oxide as is the case with chloral hydrate at 60°. When two of copper are reduced by 1 atom of uric acid that I am led gaseous products on combining form a dissociable com

,} Chemical Notices from Foreign Sources. June 6, 1879.

251 pound the combination only takes place when the sum The author has obtained iso-angelic acid along with of the tensions of the components exceeds the dissocia- ethyl-oxy-valeric acid on causing the bromo-iso-valerate tion-tension of the compound.

of ethyl to act upon the ethylate of sodium in an alcoholic Determination of Glucose in Blood.-P. Cazeneuve. solution. -A reply to the criticisms of MM. d'Arsonval and Picard Transformation of Camphic Acid into Camphor.(Comptes Rendus, 1879, pp. 753 and 755).

J. de Montgolfier.-On heating calcic camphate and Contributions towards the History of Beer-yeast formiates together the author obtained camphor, well and of Alcoholic Fermentation : Physical and characterised by its composition and properties, and acPhysiological Action of Certain Substances, Saline companied by camphren, an isomer of phoron. or otherwise, upon Normal Yeast.-A. Béchamp.Yeast which has undergone the influence of sodic acetate,

No. 19, May 12, 1879. and which has been well washed and drained, can no The Vision of Colours, especially the Influence longer be as completely fluidified by a new addition of exercised upon the Vision of Coloured Objects in acetate. Yeast, after a first treatment with the acetate, Rotatory Motion when Observed Comparatively with and whilst still impregnated with this salt, is still capable Identical Bodies in a state of Rest.-E. Chevreul.of undergoing fermentation. Yeast which has been, after This is a somewhat diffuse extract from a recent work by two or three treatments with acetate, deprived of the the author, and does not admit of useful abstraction. greater part of its soluble matters is nevertheless capable Bases Derived from Aldol-ammonia.--A. Wurtz.of setting up energetic fermentation in cane-sugar. Ammonia, when reacting upon aldol, gives rise to various No. 18, May 5, 1879.

bases, whose nature varies according to the conditions of

the experiment. At 100° there are formed certain oxy. Certain Derivatives of Durol (a-Tetra-me:hyl- genous bases soluble in water, the study of which is benzol).-MM. Friedel, Crafts, and Ador. — The authors still incomplete. At 140° to 180°, and in presence of an have obtained a compound, which may be named phenyl. excess of ammonia, dark-coloured oily bodies are formed, duryl-carbonyl, if we give the name duryl to the mon. soluble in ether. A mixture of liquid and volatile bases atomic residue of durol, from which i atom of the is obtained on submitting aldol-ammonia to dry distillahydrogen of the benzenic nucleus has been removed. tion in a current of ammoniacal gas. At the same time there is formed another compound, almost insoluble in boiling alcohol, duren-dicarbonyl care. The author has examined 282 workmen who use

Effects of Inhaling Oil of Turpentine.-M. Poindiphenyl or duren-dibenzoy!, which, if treated at a boiling this oil in their trades, and has kept animals for several heat with melting potassa, is resolved into benzoic acid

months in a medium strongly charged with its vapour. and durol.

Among the workmen the symptoms were headache, Crystals extracted from Cast-iron by means of dizziness, watery eyes, weakness of sight, especially in Ether or Petroleum.-J. Lawrence Smith.-On treating artificial light, cough, and troubled digestion. In most comminuted cast-iron with these solvents, on the

cases the constitution became habituated to this agent, spontaneous evaporation of the liquid, the author ob- but sometimes a change of employment was necessary, tained acicular crystals consisting principally of sulphur, | The animals experimented upon remained in a normal and absolutely similar to those extracted by the same condition if good ventilation was maintained. In conprocess from meteoric iron. M. Berthelot, to whom the fined air death ensued in consequence of congestion oi author had forwarded specimens of the crystals, stated the brain, lungs, &c. that he had obtained similar bodies by the action of pure ether upon octahedral sulphur and upon anhydrous iron

Two Applications of the Method of MM. Fizeau sulphides. It thus appears that even neutral solvents do and Foucault.-M. Mouton.-A mathematical paper not

suitable for abstraction. not in all cases act by simple solution upon the bodies with which they come in contact, but effect also a che- Thermic Researches upon Silicic Ether.-J. Ogier. mical alteration.

-The mean heat of formation of silicic ether is – 11'5 cals. Effects of Carbonic Sulphide upon the Radicular

Action of Ammoniacal Salts upon Certain Metallic System of the Vine.-M. Boiteau.—The author con- Sulphides, and Application of the Facts Observed cludes that this agent in doses of 6 to 10 grms. destroys to Mineral Analysis.-Ph. de Clermont.-Bismuth, by poisoning all the parts of the root system which are

cadmium, and copper sulphides are not affected if boiled within a radius of about 10 centimetres of the point where with a solution of sal-armoniac, as is also the case wi:h it is applied. This action is produced in the parts situate

mercurous and mercuric sulphides. Antimony trisulphide from 20 to 35 centims. below the surface. He still re

is completely decomposed by sal-ammoniac, yielding amcommends the use of this sulphide, applied at a distance monium sulphide, which escapes, and antimony chloride, of more than 10 centims, from the main root.

which remains in solution. Stannic sulphide yields

stannic acid and no tin dissolves. Stannous sulphide is Thermic Formation of Hydrogen Silicide.-J. Ogier. ...The heat disengaged in the combustion of requiv. of similarly decomposed, leaving stannous oxide. Metals this compound is 324°3 cals., and the mean heat of its solutions, but converted by ammonic hydrosulphate either

not thrown down by hydric sulphide from their acid formation is 24.8 cals.

into sulphides or insoluble oxides, after the action of this Limit of the Separation of Alcohol and Water by reagent, behave in a peculiar manner with sal-ammoniac. Distillation.-J. A. Le Bel.—The greatest degree of It is already known that manganese sulphide dissolves as concentration obtained by repeated rectifications was chloride. Iron sulphide in the same manner gives iron 96'5 per cent. On rectification over quick-lime an alcohol chloride. Nickel and cobalt sulphides dissolve likewise, or 98.5 was produced. When this spirit was submitted to though more slowly. Zinc sulphide resists longer, but fracional distillation the water passed over first, and the ultimately dissolves also. Alumina and chromic oxide residue was the most highly alcoholic. After three recti precipitated by ammonic hydrosulphate are known to be fications the first portions marked 97'4 and the residue insoluble in sal-ammoniac. On these reactions the author 993. The author finds that amylic alcohol from wines founds a method for the separation of certain metals. If has not the repulsive odour of fusel oil or of the crude a solution contairs cobalt, nickel, manganese, iron, amylated alcohols of (beet-root) treacle. This odour, alumina, chrome, and zinc, it is precipitated with am. and possibly the injurious physiological action of the monic hydrosulphate, the mixture added to a boiling higher alcohols, may possibly, he considers, be due to the solution of sal-ammoniac, and kept in ebullition for a presence of certain empyreumatic compounds.

sufficient time. On filtering, which is effected rapidly, A New Isomer of Angelic Acid.-E. Duvillier.- | the filtrate contains all the iron and manganese, part of

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