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42

Chemical Notices from Foreign Sources.

CKWICAL NEW, 1 January 24, 1879.

On Thymo-oxy-cuminic Acid.-L. Barth. The tains per litre 33 grms. molybdic acid, 141 grms. N203 author describes the preparation, properties, and deriva- and 1994 grms. NHg. When precipitating phosphoric tives of this acid at considerable length.

acid the quantity of free nitric acid must always be more On Idrialin.-G. Goldschmiedt.-The author finds than enough to prevent the formation of a precipitate in this body to contain 91'71 carbon and 5'32 hydrogen, and

vdrogen, and the absence of phosphoric acid, but a considerable quan

the absence of phosph declares that he cannot see why it should rank with the l fity of nitrate of ammonia may be dissolved in the liquid. aromatic hydrocarbons.

į In ordinary cases the phosphoric acid will be totally pre.

cipitated in less than twelve hours, if so much molybdic · Double Salts of Cuprous Hyposulphite (Second

mixture is added as to make up tour times the volume of Memoir).-F. Kessel.--Not suitable for abstraction.

the phosphoric solution, and if in every 100 c.c. of the On a-Oxpara-toluylic Acid.--E. v. Gerichten and W.

mixture there are dissolved 25 grms. nitrate of ammonium. Rössler.-The authors pronounce this acid identical with For washing the precipitate is employed a strong solution Flesch's oxy-toluylic acid.

(20 per cent) of ammonic nitrate, to which at first one. Adion of Fuming Nitric Acid and of Nitrous ! thirtieth of its volume of nitric acid is added. The washing Acid upon Benzol-sulphinic Acid.-W. Kanig.–The is completed when the washings are no longer coloured author seeks to ascertain whether C18H16N2S306 contains by potassium ferrocyanide. The precipitate may be intact the three benzol-sulphuryl residues.

brought into a condition fit for weighing by the following On Organic Thio-compounds.-O. Wallach. The operations : -After removing most of the ammonic nitrate author examines the behaviour of alkyl-bromides and by me

od l by means of water the contents of the filter are washed iodides upon natrium-thiacetanilid.

| into a weighed porcelain crucible. Anything adhering to

the paper is dissolved in a little warm dilute ammonia, New Mode of Formation of Phenyl-glyoxylic

the solution is concentrated by evaporation, nitric acid is Acid.-L. Claisen and F. H. Morley. -Ethyl-glyoxylic added in excess, the whole is quickly poured into the ethyl.ether and mercury diphenyl are readily transformed porcelain crucible, the liquid is expelled by evaporation, with little loss into phenyl-glyoxylic ethyl-ether and mer.

and the nitrate of ammonia driven off by a flame cury mono-phenyl-chloride.

moderated by wire gauze. The residue is hygroscopic, On Triphenyl-methan.-E. and 0. Fischer.—The and must be cooled over sulphuric acid and quickly authors have obtained from this compound both tri- | weighed in the covered crucible. phenyl-methan-cyanide and triphenyl-acetic acid. They Diazo-compounds of the Fatty Series (First Memoir). effected this object by heating triphenyl-inethan-chloride -W. Zorn.-.By treating ethyl-iodide with silver nitrosyi with an excess of mercury cyanide.

the author obtained a compound C2H5NO, almost as Action of Halogens upon the Salts of Guanidin. readily and as violently explosive as the chloride of -). Kamenski.-In this memoir the author examines the nitrogen. behaviour of guanidin carbonate with bromine and chlorine. | Discovery of Vanillin in Siamese Benzoin.-P.

Chrysarobin and Alleged Chrysophanic Acid in Jannasch and C. Rump.-This paper contains merely the Goa-powder.-C. Liebermann and P. Seidler.--The analytical evidence that the substance detected was vanillin. authors hold that the substance originally present in this Preparation of Nitrous Acid.-G. Lunge. For the powder is not chrysophanic acid, and that acid, as actually

preparation of nitrous acid, whether by means of arsenious detected by Attfield, they consider a product of conversion.

acid or starch, should be used nitric acid of sp. gr. I'30 to For the original substance they propose Attfield's synonym

1-35, and almost entirely free from hyfonitrous acid. chrysarobin.

Ation of Ethyl Iodide upon Silver Maleate and Synthesis of Anthrarufin and Chrysazin from Fumarate.-R. Anschütz.-The author's object is to Anthracen.--C. Liebermann.-On treating anthracen decide the isomerism of maleic and fumaric acids by a with sulphuric acid the authors obtained two disulpho.

sulpho comparative study of their derivatives. . acids, one of which lead through an easy series of con- i versions to anthrarufin (Schunck and Römer) and the

On Alizarin Blue.-C. Græbe.-The author shows by

his experiments that the corre& formula for this com. other to chrysazin.

pound is C,H2NO, By heating it with zinc-powder he Disulphanthracenic Acid and its Conversion into

obtains a new base, CA HIIN, whose salts are all goldea Anthrarufin.-C. Liebermann and K. Boeck. A detailed

yellow, and in solution display an intense green fluoresdescription of the former readion mentioned in the pre

cence. vious paper.

Simple Method for Obtaining the Aldehydins.-A. Formulæ of Rhamnetin and Xantho-shamnin.-C.

Ladenburg.-The author agitates dilute aqueous solutions Liebermann and O. Hörmann.—The authors assign to

of an ortho-diamin hydrochlorate with an aldehyd, when rhamnetin the formula C12H160s, and to xantho-rhamnin

the corresponding aldehydin is formed with liberation of C48H66022

heat. Certain Derivatives of Cærulignon.-H. Ewald.

Experimental Determinations of Position.-A. A description of hydrocærulignon potassium, hexa.

| Ladenburg.-Not suitable for abstraction. methoxyl-diphenyl, dibrom-hexa-methoxyl diphenyl, and

On Certain Phenyl-aldehydins.-A. Ladenburg and dichlor-hexa-methoxyl-diphenyl. Three Isomeric

T. Engelbrecht.-An account of phenyl-benzaldehydin Tolidins.-A. Goldschmidt.

in and phenyl-furfuraldehydin.

In addition to the tolidin obtained by Petriew the author has obtained two others. The paper contains an account of

On the Aldehydins.-A. Ladenburg.-The author meta-azo-toluol, meta-hydrazo-toluol, and sulphate of

describes dibenzyliden-amido-benzoic acid; tolufurfur.

aldehydin, which latter body possesses an intense bitter tolidin. On Hydrocarbons obtained by the Action of Alu.

taste recalling that of strychnin and acts upon animals as minium Chloride upon Chlor-methyl and Benzol. a powerful poison ; and, lastly, phenyl-anisaldehydin. E. Ador and A. Rilliet.-An examination of xylols.

Naphtho-picric Acid and Certain of its Derivatives. Determination of Phosphoric Acid as Ammonic T. Dichl and V. Merz. The authors describe the prePhospho-molybdate.-R. Finkener.-Hydrochloric and para

and | paration of this acid and the following of its derivatives : nitric acids hinder or delay the formation of the yellow

1-Amido-diimido-naphthol hydrochlorate, the chromate

precipitate, whilst dissolved molybdic acid promotes or of the same name, and the platinic double salt. accelerates it. Hydrochloric acid in the solution acts more The Formula of Uric Acid.-H. B. Hill.—The powerfully than nitric, and ammonic nitrate more power-author admits an error as to the originai authorship of a fully than ammonic chloride. The author's solution con- structural formula.

Tétra-nitroxy-sulpho-benzide.--J. Annaheim.-This 5420 pp., Royal 32mo., French morocco, gilt edges, price 58., compound, C12H6N,SO12, is a solid, straw.coloured body, A POCKET. BOOK FOR CHEMISTS of an intensely bitter taste, melting at 253°, and della | n CHEMICAL MANUFACTURERS, METALLURGISTS grating at higher temperatures.

DYERS, DISTILLERS, BREWERS, SUGAR. REFINERS

PHOTOGRAPHERS, STUDENTS, &c., &c. By THOMAS BAYLEY, On Mucobromic Acid.-0. R. Jackson and H. B.

Assoc, R.C. Sc. Ireland, Analytical and Consulting Chemist, Demon Hill.-An account of the preparation and of certain de. strator of Practical Chemistry, Analysis, and Assaying, in the Mining rivatives of this acid.

School, Bristol.

Synopsis of Contents. Analysis of the Mineral Spring Marienbrunnen, at Atomic Weights and Factors-Useful Data-Chemical Calculations Huckstelle, Westphalia.-H. Vohl.

--Rules for Indirect Analysis-Weights and Measures-ThermoAnalysis of the Bitter Water of Rákóczy, from

meters and Barometers-Chemical Physics-Boiling points, &c.

Solubility of Substances-Methods of obtaining Specific GravityBuda.-H. Vohl. The interest of these two papers, if Conversion of Hydrometers-Strength of Solutions by Specific Graany, is medical rather than chemical.

vity-Analysis-Gas Analysis-Water Analysis-Qualitative Analysis and Reactions-Volumetric Analysis-Manipulation - Mineralogy Assaying - Alcohol - Beer --Sugar - Miscellaneous Technological

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ducts, Petroleum, Milk, Tallow, Photography, Prices, Wages, &c.

London: E. and F. N. SPON, 46, Charing Cross. Gluten in Grain.-Will any of your readers inform me what grain

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married man. Apply to Edward Toynbee, Saxilby, Lincoln. 1. On the Thickness of the Antarctic Ice, and its Relations to

- MANUFACTURING CHEMIST. that of the Glacial Epoch. By James Croll, LL.D., F.R.S. II. Gravitation as a Factor in the Organic World. By William Wanted, a Young Man having a Good Know.

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experience acquired, and all particulars, to Chemist, care of Messrs. IV. The Course of Nature. By Prof. Simon Newcomb. V. Peruvian Antiquities. By E. R. Heath, M.D.

Gi Street and.Co., 30, Cornhill, E.C. · Notices of Scientific Works, Obituary, &c.

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&c. Prices and samples on Application,
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during which time thau have interest and reviews of scientific works, the MONTHLY JOURNAL OF them to the Chemical Trade, believing there is nothing better in the • SCIENCE will contain abstracts of papers read before the Scientific market."-(Sigoed) WILLIAM HUNT and SONS, Lea Brook Societies - Reports on all Important Scientific Discoveries -A Alkali Works, near Wednesbury, Staffordshire, February, 1878. General and Critical Review of the Results of Biological Research

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44

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CREMICAL NEWS,

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[graphic]
[graphic]

CASE 63s.

WOLVERHAMPTON.

THE CHEMICAL NEW S. 16-inch chemical balance by Oertling: The exact length

Vol. XXXIX. No. 1001.

News

Estimation of Small Excesses of Weight. January 31, 1879.)

| The results given in this paper were obtained with a of the half beam (a) measured by a dividing engine is 20*2484 centimetres.

To find the Moment of Inertia MI% of the Beam.-The simplest way theoretically would appear to be this. Find the times of vibration ti tz and the deflections 0, 02 due to

the same excess þ with two differen: loads P, P2 in each ON THE

pan. Equating the values of p given for each by equation ESTIMATION OF SMALL EXCESSES OF WEIGHT | (4) we have BY THE BALANCE FROM THE TIME OF

Mglo +2Pjar Oztro
VIBRATION AND THE ANGULAR DEFLECTION

Mg1° +2Pza:=@rtz?
OF THE BEAM.*

An equation which will give MgI: in terms of known

quantities. But on trial it was found that a very small By J. H. POYNTING, B.A., B.Sc.

proportional error in the observed time made a large error

in the value of Mgl”, and the following method, that While working last year on an experiment to determine

ron an experiment to determine | usually adopted in magnetic observations, was employed the mean density of the earth by the balance, I had to (in preference. A stirrup was suspended by a platinum measure such an exceedingly small difference of weight, 1 wire, and its time of vibration (ti) against the force of that I could not at that time estimate it by means of a torsion (u) of the wire was observed. The moment of rider, but was obliged to adopt the method described in inertia of the stirrup being S we havethis paper. Stated generally, it consists in treating the

tge="’S balance as a pendulum. Knowing the nature of the pendulum (that is its moment of inertia) and its time of vibra

fle tion, we can calculate what force acting at the end of one The time of vibration (ta) was then observed when a cylinarm of the beam will produce a given angular deflection. drical brass bar of known moment of inertia B was in. It is, in fact, an application to the common balance of the serted in the stirrup. We now havemethod which has always been used with the torsion

tzo=7*(S+B) balance when it has been necessary to calculate the forces measured in absolute measure. I cannot find any record of a previous application of the method, and as it might | The bar was then removed and the balance beam inserted be of use in very delicate weighings, or in verifying the | in its place, and the time of vibration (tz) givessmall weights in a laboratory, I have thought it worth while to give a full account of it.

tge=7*(S+MI) When small quantities of the second order are neglected, and the oscillations are of the first order, it will easily be From these three equations, eliminating S and 4 we found that the equation of motion of the beam of the obtainbalance is— (MI: +2Pa:ë+(2Ph+Mgk)e=ap... (1)

122-tis

Now Bg was calculated from the weight and dimensions Where MI:=moment of inertia of beam about central

| of the bar to be 6332.83 (in centimetres and grammes

| The observed times were t; = 3.6792"; t2 = 4495" knife edge. M=mass of beam.

tz=7*1483". From these values we finda=half length of beam.

Mg =35656.* P=weight of either pan and the mass in it.

To Measure 0.--The angle of deflection was measured h-distance of line joining terminal knife edges below the by the number of divisions of the scale which the pointer central knife edge.

moved over. As the length of the pointer is 32.1006 centik=distance of centre of gravity of beam below central

metres, while 20 divisions of the scale measure 2.3658 knife edge.

centimetres, a tenth of a division, in terms of which the p=small excess in one pan.

deflection was measured, corresponds to an angle of O=angular defle&ion in circular measure produced by p. 0.0003996. The oscillations were observed from a distance g=gravity.

of 6 or 8 feet by a telescope. The resting-point (i.e., the

point where the balance would be in equilibrium) was found If Ö=0 we have the position of equilibrium given by—

in the usual way by observing the three successive extre

mities of two swings, and taking the mean of the second 0= Phi Mek .......... (2)

and the mean of the first and third. Five determinations The semi-periodic time is

of the resting-point were usually made with the excess

to be measured alternately added and removed. From MI: +2Pas

these five, three values of the deflection (n), due to the

excess, were calculated in a manner which will be seen ...cici (3) from the example below. V 2Ph+ Mgk

The Time of Vibration.—This was found from several From equations (2) and (3) we can eliminate 2Ph+ Mgk, determinations of the time of ten oscillations. The method obtaining

will be seen from the example. No correction was Mg19+2Pas

needed for the resistance of the air as long as the vibra. . . .. .. . P=#"

(4) tions did not exceed two divisions of the scale. When, agt

however, they were much more than that the time of vi. Prom this expression it appears that if we know the bration was found to increase with the arc. As the time moment of inertia of the beam, its length, and the weight of vibration frequently changes slightly, probably through at each end, we can find the excess ħ from the time of variations of temperature, it was usually observed before vibration and defle&ion.

* To this a small correction should be added if the adjusting bob is * Read before the Manchester Literary and Philosophical Society, not in its lowest position. This amounts to 7-6 for each turn of the December 10, 1878.

scrow, and may therefore in general be neglected.

Me_B(tz: -- tq:)

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CHEMICAL NEwe,

46

Apparatus for Production of Ferrous Salts for Titration.

CHEMICAL NEWS

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12

127

and after the determination of the deflection (n), and the an angle of O'0003996 in circular measure formula (4), mean of the two taken as the true time.

| expressed in milligrms., becomes-
The following example of the determination of the
value of a centigramme rider by placing it half-way along
the beam will sufficiently explain the details of the
method.

In our present example,
TIME OF VIBRATION AT COMMENCEMENT.

n=35.83 Pointer apparently Moving from Left to Right.

t='T?=120725"
Observed time

Observed time
No. of of passage of No. of of passage of Time of 10

Mglo =35651
Vibration pointer through Vibratn. pointer through Vibrations.

2Pa' = 24704
'resting point.
resting point.

p=5*724 milligrm.
ih 15'36" 10 17'43" 127
16' 1"
18' 8"

The length of time occupied in this determination was 16'25'5

18'33":5 127 not quite a quarter of an hour. .
16'52"
18'59" 127

The following table contains a series of results which I

have obtained of the weight of two centigramme riders, the Mean value of 10 vibrations

· 127 first of which was accidentally destroyed after the conclujih 15'49"

sion of the fourth determination. As the rider was always 17'56"

II 16'14"

placed at division 5 on the beam, the values given in the
18'21"
13

127
16'39":5 15 18'46" 126.5

table are double those actually obtained :-
17' 5" 17 19'11":5 126'5 No. of Mg12 +2Pa?

Weight of rider Mean Expt.

in secs.

in milligrammes. Value. Mean value of 10 vibrations .. .. .. 126.75

145364 8.921 13.458 9978) Mean of means= 126875.

309356 17.65

10'05

519769 t=12.6875.

9.96 20'435 19*12 130355 13:10

34°71

10'47 DETERMINATION OF DeflectiON N.

130355 12.87

11.44) Mean of pre

130355 1272 35-50 II'35 Extremities Resting- ceding and

Deflection Excess

130355 due to

120725 3583 II'45 of

11435 Weight.

Point. succeeding
Oscillation.

Excess,

12.81 130355

35'5 11'20 m.grms. resting-points.

130355 12'903 36-37 109

II'31

19:406 22'08 Added

454405

10'58) ..

96 ..

102'5

127

25:49

9:55 m.grms.

36.6

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The apparatus usually employed to procure the absence Removed.. 55 67-25 1025 35625

of atmospheric air during the solution of metallic iron in acids consists of a flask fitted with a cork, through which is passed a tube bent twice at right angles. When in use

the free end of this tube is made to dip below the surface Added . ..

of water contained in a second flask or small beaker,

The chief defects of this arrangement are :
Mean value of n=35*83.

Ist. Want of portability.

2nd. Necessity for some form of support for tube. Time of VIBRATION at End.

Having recently had occasion to execute a considerable

number of determinations of metallic iron in samples of Pointer apparently Moving from Left to Right. steel and iron, I constructed an apparatus entirely free Observed time Observed time

from these defects, and very much more simple and con. No. of of passing of No. of of passage of Time of 10

venient to manipulate. The following is a description of tion. pointer through Vibratn. pointer through Vibrations. resting-point. resting-point.

the new arrangement, which will be readily understood by Ith 26'19" IO

28'27"

128

the aid of the accompanying cut. 26'44":5 12 28'53"

A is a flask of 200 c.c. capacity ; B, a glass funnel 7 m.m.

12805 29'18"

diameter ; c, a glass tube of such a size as just to pass 27'35":5 16 29'44"

128.5

through stem of funnel B. D, an india-rubber joint con

neating B and c and forming a perfectly tight joint; E, an Mean value of to vibrations .. .. 128.25

india-rubber stopper, bored so as to pass stiffy upon c.

Perhaps a word upon the construction and use of the 26'32"-5 11 28'39" 126'5 apparatus may be admissible. Having selected a tube of 26'58" 13 29' 5"

127 the proper size, the upper bend is turned on so that the 27'23":5 15 29'30":5 127 point of the tube c, which should be narrowed to r5 m.m., 27'49" 17 2 9'56'':5 127'5

falls into the apex of B. Bis then placed in position and

secured by D; the stopper e is next fitted on c, and finally Mean value of io vibrations .... 127

the lower bend of c is turned on, taking care to allow so Mean of means=127.625.

much tube as will prevent e being injured by heat. ta=1207625.

* For this as for several other cases I removed the pans, and hung

the weights directly by finc wires from the suspended pieces. By this Rei

ering that one-tenth of a division of the scale is ' means the resistance of the air was very much diminished.

27'10"

128

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