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British Association for the Advancement of Science. { ,

July 14, 1876. MISCELLANEOUS.

TO CORRESPONDENTS.

American Chemical Society.--At a meeting of Ame

H. Cant.-Hopkin and Williams, or from Dr. Theodor Schuchardt

Chemische Fabrik, Gorlitz. rican chemists, held in April last at the New York College of Pharmacy, it was resolved to form a society, to be called “The American Chemical Society," and at a

THE subséquent meeting the following officers and committees were appointed :-President- John W. Draper. Vice. QUARTERLY JOURNAL OF SCIENCE. Presidents-). Lawrence Smith, Frederick A. Genth, E. Hilgard, J. W. Mallet, Charles F. Chandler, Henry

Edited by WILLIAM CROOKES, F.R.S., &c.
Morton. Corresponding. Secretary-George F. Barker.
Recording Secretary-Isidor Walz. Treasurer-W. M.

Now ready No. LI., July, 1876, price 5s.
Habirshaw. Librarian — P. Casamajor. Curators

CONTENTS. Edward Sherer, W. H. Nichols, Frederick Hoffmann.

1. On the Geological Age of the Deposits containing Fligt Im. Committees on Papers and Publications-Albert R. Leeds,

plements, at Hoxne, in Sussex, and the Relation that Herrmann Endemann, Elwyn Waller. Committee on

Paleolithic Man Bore to the Glacial Period. By Thomas Nominations-E. P. Eastwick, M. Alsberg, S. St. John,

Belt, F.G.S.

11. A Scheme of Water Supply for Villages, Hamlets, and Country Charles Fröbel, Chas. M. Stillwell.

Parishes of the Central and Eastern Counties. By Prof. Experiments with Frozen Dynamite.-Some in.

Hull M.A., F.R.S., F.G.S.

III. Vivisection. teresting experiments were recently made at the works of

IV. Infusorial Earth and its Uses. the British Dynamite Company at Stevenston, Ayrshire, V. The Nizam Diamond - The Diamond in India. By Captain with the view of proving that dynamite in a frozen state

Richard F. Burton. is as safe to handle and to transport as in an unfrozen vil. The Loan Exhibition of Scientific Apparatus at South Ken

VI. Certain Phases of Bird Life. By Charles C. Abbott, M.D. state. Professors James Thomson and Bottomley, of the

sington. University of Glasgow, were present. In the first expe- Notices of Scientific Works, Progress of the Various Sciences, &c. riment several cartridges in a frozen state, and in some

London : 3, Horse-Shoe Court, Ludgate Hill, E.C. parts beginning to thaw, were thrown one by one from the plosion. In the second experiment, a block of iron about Chemical Technology, or Chemistry in its

By THOMAS 400 lbs. weight, was allowed to fall from a height of about RICHARDSON and Henry WATTS. Second Edition, illustrated with 20 feet on a light wooden box containing 20 lbs. of dy. numerous Wood Engravings. namite cartridges in a frozen state, and with slight signs

Vol. I., Parts 1 and 2, price 368., with more than 400 Illustrations. of incipient thawing in spots more exposed to the warmth of the air. The box was smashed, and the cartridges Fuel: Production of Light: Secondary Products of the Gas Manu.

Natute and Properties of Fuel: Secondary Products obtained from were crushed flat and pounded together, but there was no facture. explosion. The crushed cartridges were next made up

Vol. I., Part 3, price 33s., with more than 300 Illustrations. into two heaps to be exploded. The ordinary detonator shatters but does not explode the frozen dynamite. The Compounds: Soda, Potash : Alkalimetry: Grease.

Sulphur and its Compounds: Acidimetry: Chlorine and its Bleaching explosion was therefore effected by inserting in each heap a small unfrozen cartridge, with the ordinary detonator

Vol. I., Part 4, price 219., 300 Illustrations. inserted into it, and then firing this off by a Beckford Silicates of Potash and Soda : Phosphorus, Borax: Nitre : Gun

Aluminium and Sodium : Stannates, Tungstates, Chromates, and fuse. The two heaps were exploded successively, and it Powder: Gun Cotton. is worthy of remark that the explosion of the first, though

Vol. I., Part 5, price 368. very violent, did not set the other off.

Prussiate of Potash: Oxalic, Tartaric, and Citric Acids, and Appen. British Association for the Advancement of dices containing the latest information, and specifications relating to Science.—The following are the officers of the forty-sixth the materials described in Parts 3 and 4. annual meeting of the British Association which will commence at Glasgow on Wednesday, September 6th, BAILLIERE AND CO., 20, King William Street, Strand. 1876:-President designate-Prof. Thos. Andrews, M.D., LL.D., F.R.S., Hon. F.R.S.E., in the place of Sir Robert BERNERS COLLEGE OF CHEMISTRY:-Christison, Bart., who has resigned the Presidency in EXPERIMENTAL MILITARY and NAVAL SCIENCES, consequence of ill health. Vice-Presidents elect-His under the diregion of Professor E. V. GARDNER, F.E.s., &c.; Grace the Duke of Argyll, K.T., F.R.S., &c.; the Lord of the late Royal Polytechnic lastitution and the Royal Naval College.

The Laboratory and Class Rooms are open from a to s a.m. and Provost of Glasgow ; Sir William Stirling Maxwell, Bart., from 7 to 10 p.m.daily. M.A., M.P. ; Prof. Sir William Thomson, D.C.L., F.R.S., Especial facilities for persons preparing for Government and other

examinations. &c.; Prof. Allen Thomson, M.D., LL.D., F.R.S., &c.;

Private Pupils will find every convenience. Prof. A. C. Ramsay, LL.D., F.R.S., &c. General Secre

Analyses, Assays, and Practical Investigations connected with taries-Capt. Douglas Galton, C.B., D.C.L., F.R.S., &c. ; | Patents, &c.,conducted. Dr. Michael Foster, F.R.S. Assistant General Secretary for prospectus, &c., apply to Prof. E v.G., 44, Berners-street, w -George Griffith, M.A., F.C.S., &c. General Treasurer Prof. A. W. Williamson, Ph.D., F.R.S. Local Secre.

MORRIS TANNENBAUM, 37; FITZROY taries-Dr. W. G. Blackie, F.R.G.S. ; James Grahame; STREET, offers Jewellers, Mineralogists, Lapidaries, and J. D. Marwick. Local Treasurers-Dr. Fergus; A. S. especially. Collectors of Rare Cut Gems (which he possesses in k!l M'Clelland. The President of Section A (Mathematical existing kinds), large Collections of Fine Hyacinths in all Colours,

and Yellow Amethysts, Jargon, and Physical Science) will be Prof. Sir Wm. Thomson, Olivine, Fossils, Fine Collections of Shells, Thousands of Indian D.C.L., F.R.S.; of Section B (Chemical Science), Mr. Pebbles. Polished Agates, &c., Starstones and Catseyes, Garnets, W. H. Perkin, F.R.S. On Thursday evening, Sept. 7th, Matrix, Fine Crystallised Rubies and Brazilian Topazes, ind at 8 p.m., there will be a Soirée ; on Friday evening,

Thousands of Rare Opals. Specimens and for Cuttings. Orders Sept. 8th, at 8.30 p.m., a Discourse; on Monday evening, effected to all parts of the world. Sept. lith, at 8.30 p.m., a Discourse by Prof. Sir C. Wy. ville Thomson, F.R.S.; on Tuesday evening, Sept. 12th, Mawson and Swan are now able to supply at 8 p.m., a Soirée ; on Wednesday, Sept. 13th, the con

. cluding general meeting will be held at 2.30 p.m.

11 and 15, Mosley Street, Newcastle-on-Tyne,

ON

CHEMICAL News,

Repulsion Resulting from Radiation. July 21, 1876.

23

This instrument proved that, at a rarefa&ion so high THE CHEMICAL NEWS. that the residual gas was a non-condu&or of an induction

current, there was enough matter present to produce mo

tion, and therefore to offer resistance to motion. That Vol. XXXIV. No. 869.

this residual gas was something more than an accidental accompaniment of the phenomena was rendered probable by the observations of Dr. Schuster, as well as by my own experiments on the movement of the floating glass case of a radiometer when the arms are fixed by a magnet.

My first endeavour was to get some experimental means REPULSION RESULTING FROM RADIATION. of discriminating between the viscosity of the minute INFLUENCE OF THE RESIDUAL GAS.* quantity of residual gas and the other retarding forces,

such as the friction of the needle-point on the glass cup (PRELIMINARY NOTICE.)

when working with a radiometer, or the torsion of the By WILLIAM CROOKES, F.R.S., &c.

glass fibre when a torsion-apparatus was used. A glass bulb is blown on the end of a glass tube, to the upper part

of which a glass stopper is accurately fitted by grinding. I HAVE recently been engaged in experiments which are To the lower part of the stopper a finc glass fibre is ce. likely to throw much light on some obscure points in the mented, and to the end of this is attached a thin oblong theory of the repulsion resulting from radiation. In these plate of pith, which hangs suspended in the centre of the I have been materially assisted by Prof. Stokes, both in globe: a mirror is attached to the pith bar, which enables original suggestions and in the mathematical formula its movement to be observed on a graduated scale. The necessary for the reduction of the results. Being pre- stopper is well lubricated with the burnt india-rubber vented by other work from completing the experiments which I have already found so useful in similar cases (207). sufficiently to bring them before the Royal Society prior The instrument is held upright by clamps, and is connected to the close of the session, I have thought that it might to the pump by a long spiral tube. The stopper is fixed be of interest were I to publish a short abstract of the rigidly in respect to space, and an arrangement is made by principal results I have obtained, reserving the details which the bulb can be rotated through a small angle. The until they are ready to be brought forward in a more pith plate, with mirror, being suspended from the stopper, complete form.

the rotation of the bulb can only cause a motion of the In the early days of this research, when it was found pith through the intervention of the enclosed air. Were that no movement took place until the vacuum was so there no viscosity of the air, the pith would not move; good as to be almost beyond the powers of an ordinary but if there be viscosity, the pith will turn in the same di air-pump to produce, and that as the vacuum got more rection as the bulb, though not to the same extent, and, and more nearly absolute so the force increased in power, after stopping the vessel, will oscillate backwards and it was justifiable to assume that the action would still forwards in decreasing arcs, presently setting in its old take place when the minute trace of residual gas which position relatively to space. theoretical reasoning proved to be present was removed. It was suggested by Prof. Stokes that it would be deThe first and most obvious explanation therefore was that sirable to register not merely the amplitude of the first the repulsive force was dire&tly due to radiation. Further swing, but the readings of the first five swings or so. consideration, however, showed that the very best vacuum This would afford a good value of the logarithmic decre: which I had succeeded in producing might contain enough ment (the decrement per swing of the logarithm of the matter to offer considerable resistance to motion. I have amplitude of the arcs), which is the constant most desir. already pointed out that in some experiments, where the able to know. The logarithmic decrement will involve rarefaction was pushed to a very high point, the torsion the viscosity of the glass fibre, but glass is so nearly perbeam appeared to be swinging in a viscous fluid (194), and fedly elastic, and the fibre so very thin, that this will be this at once led me to think that the repulsion caused by practically insensible. radiation was indire&ly due to a difference of thermome- According to Prof. Clerk Maxwell the viscosity of a gas tric heat between the black and white surfaces of the should be independent of its density; and the experia moving body (195), and that it might be due to a secondary ments with this apparatus have shown that this is praci. action on the residual gas.

cally correct, as the logarithmic decrement of the arc of On April 5, 1876, I exhibited, at the Soirée of the Royal the oscillation (a constant which may be taken as defining Society, an instrument which proved the presence of resi- the viscosity of the gas) only slightly diminishes up to as dual gas in a radiometer which had been exhausted to a high an exhaustion as I can conveniently attain-higher, very high point of sensitiveness. A small piece of pith indeed, than is necessary to produce repulsion by radi was suspended to one end of a cocoon fibre, the other end ation. being attached to a fragment of steel. An external mag- I next endeavoured to measure, simultaneously with the net held the steel to the inner side of the glass globe, logarithmic decrement of the arc of oscillation, the rethe pith then hanging down like a pendulum, about a pulsive force produced by a candle at high degrees of millimetre from the rotating vanes of the radiometer. By exhaustion. The motion produced by the rotation of the placing a candle at different distances off, any desired ve- bulb alone has the advantage of exhibiting palpably to locity,

up to several hundreds per minute, could be imparted the eye that there is a viscosity between the suspended to the fly of the radiometer. Scarcely any movement of body and the vessel ; but once having ascertained that, the pendulum was produced when the rotation was very and admitting that the logarithmic decrement of the arc rapid ; but on removing the candle, and letting the rota. of oscillation (when no candle is shining on the plate) is tion die out, at one particular velocity the pendulum set a measure of the viscosity, there is no further necessity to up a considerable movement. Prof. Stokes suggested complicate the apparatus by having the ground and lubri. (and, in fact, tried the experiment at the time) that the cated stopper. A movement of the whole vessel bodily distance of the candle should be so adjusted that the per- through a small arc is equally effective for getting this manent rate of rotation should be the critical one for logarithmic decrement; and the absence of the stopper synchronism corresponding to the rate at which one arm enables me to have the whole apparatus sealed up in of the fly passed for each complete oscillation. In this glass, and I can therefore experiment at higher rarefac. way the pendulum was kept for some time swinging with tions than would be possiblejwhen a lubricated stopper is regularity through a large arc.

present.

* A Paper read before the Royal Society, June 15, 1876.

* Proc. Roy. Soc., March 30, 1876.

same.

24
Action of Sodium on Benzoli

{ ,

July 21, 1876. The apparatus, which is too complicated to describe ON THE ACTION OF CERTAIN KINDS OF without a drawing, has' attached to it--a, a Sprengel

FILTERS ON ORGANIC SUBSTANCES, pump; b, an arrangement for producing a chemical

Part IV. vacuum ; ¢, a lamp with scale, on which to observe the luminous index reflected from the mirror; d, a standard

By J. ALFRED WANKLYN. candle at a fixed distance; and e, a small vacuum-tube, with the internal ends of the platinum wires close together. I can therefore take observations of

In continuing my investigation I have experimented on a

solution of strychnine. În 10 litres of London Thames 1. The logarithmic decrement of the arc of oscillation water (West Middlesex Company), which yielded when under no influence of radiation.

0'05 m.grm. of albuminoid ammonia per litre, I dissolved 2. The logarithmic decrement of the arc of oscillation 1.263 grms. of strychnine, using a little hydrochloric acid

when a candle shines on one end of the blackened (about 5 c.c. of the strong acid) to facilitate the solution. bar.

As will be seen, this solution contains Oʻ1263 grm. of 3. The appearance of the induction-spark between the strychnine per litre, or 8.841 grains per gallon. Such a

solution is bitter to the taste. platinum wires.

I drank 5 c.c. of it, and

found it to be very bitter. I measures the viscosity; 2 enables me to calculate the Submitted to the “ammonia process” the solution force of radiation of the candle ; and 3 enables me to yielded 5*20 m.grms. of albuminoid ammonia per litre. form an idea of the progress of the vacuum, according as In making the experiment on the filtration of this soluthe interior of the tube becomes uniformly luminous, tion I desired to ascertain whether or not the silicated striated, luminous at the poles only, or black and non- carbon filter preserves its power, and accordingly emconducting.

ployed the same filter which had already absorbed quinine The apparatus is also arranged so that I can try similar and morphia in previous experiments. Already the filter experiments with any vapour or gas.

had taken up about oʻ7 grm. of acid sulphate of quinine The following are some of the most important results and 13 grms. of hydrochlorate of morphia, and since which this apparatus has as yet yielded :

taking up these alkaloids had not had very large quanti*Up to an exhaustion at which the gauge and barometer ties of water passed through it. The filter was very are sensibly level there is not much variation in the vis. carefully drained of water, and then the io litres of the cosity of the internal gas (dry atmospheric air: Upon first 5 litres of filtrate were thrown away, and the remain

above-described solution of strychnine placed in it. The now continuing to exhaust, the force of radiation com

der was collected. mences to be apparent, the viscosity remaining about the The viscosity next commences to diminish, the

Submitted to the ammonia process it yielded some free force of radiation increasing. After long.continued ex

ammonia and 0'04 m.grm. of albuminoid ammonia per haustion the force of radiation approaches a maximum, litre, which shows that the filtrate was devoid of strych

nine. but the viscosity measured by the logarithmic decrement

I have sufficient confidence in the ammonia process to begins to fall off, the decrease being rather sudden after it has once commenced.

wager my life on the correctness of the results, and I Lastly, some time after the logarithmic decrement has drank 300 c.c. of the filtrate. It was not bitter, and i commenced to fall off, and when it is about one-fourth of have not experienced any symptoms of poisoning with what it was at the commencement, the force of radiation strychnine; and, as will be found on making the calcula. diminishes. At the highest exhaustion I have yet been tion, 300 c.c. of the unfiltered liquid contained about able to work at, the logarithmic decrement is about one

40 m.grms. of strychnine, which is a poisonous dose. twentieth of its original amount, and the force of repul. sion has sunk to a little less than one-half of the maxiThe attenuation has now become so excessive

ACTION OF SODIUM ON BENZOL. that we are no longer at liberty to treat the number of gaseous molecules present in the apparatus as practically infinite; and, according to Prof. Clerk Maxwell's theory,

I. the mean length of path of the molecules between their Some observers have stated* that when benzol is heated collisions is no longer very small compared with the di

or digested with sodium it is decomposed or acted upon, mensions of the apparatus.

but the nature of the product is not stated. The degree of exhaustion at which an induction. current will not pass is far below the extreme exhaustions tively inert substance like benzol is not, from theoretic

Why potassium or sodium should act upon a comparaat which the logarithmic decrement falls rapidly.

grounds, very evident. The force of radiation does not act suddenly, but takes

To prove whether sodium has any action on C6H6 an appreciable time to attain its maximum; thus proving, within a moderate range of temperature the following exas Prof. Stokes has pointed out, that the force is not due periments have been made :to radiation directly, but indirectly. In a radiometer exhausted to a very high degree of nary benzol with strong oil of vitriol for some days,

Very pure benzol was prepared, by agitating the ordisensitiveness, the viscosity of the residual gas is almost washing with potassic hydrate, and distilling from water; as great as if it were at the atmospheric pressure.

it was then dried with calcic chloride, and rectified; after With other gases than air the phenomena are different which it was further purified by several crystallisations, in degree, although similar in kind. Aqueous vapour, for the crystals of benzol being pressed between in a handinstance, retarding the force of repulsion to a great screw press) each operation, to separate any uncrystalextent, and carbonic acid acting in a similar though less lisable hydrocarbon which might remain. degree.

This benzol boils constantly at 80-50 to 81°, and its The evidence afforded by the experiments of which this vapour density and percentage composition, by combusis a br ef abstract is to my mind so strong as almost to tion, agree very closely with the calculated numbers: amount to conviction that the repulsion resulting from 8 to 10 c.c. of this benzol, along with 1 to 1'5 grm. cleanradiation is due to an action of thermometric heat be

cut sodium, was introduced into strong tubes (about tween the surface of the moving body and the case of the 15 inches long), the benzol warmed so that its vapour exinstrument, through the intervention of the residual gas. pelled the air from the tubes, which were then sealed and This explanation of its action is in accordance with recent

heated in an oil-bath to 150° C. for four hours, at the end speculations as to the ultimate constitution of matter, and the dynamical theory of gases.

“ Watts's Dictionary" (Benzene).

mum.

,} July 21, 1876. Development of the Chemical Arts.

25 of which time a tube was examined, but the sodium , decomposed by carbonate of lime, and steam at a pres. showed no further signs of action than fusion into sure of from 2 to 4 atmospheres, and the carbonate of globules. The remaining tubes were then heated to 200° manganese thus formed being heated to 300° to 400° C. to 250° C. for eighteen hours, when very little change was This procedure was carried out in the colossal establishapparent, and the surfaces of the sodium having only a ment of Messrs. Tennant, at Glasgow, but has not been very slight brownish tint.

generally adopted among manufacturers of chlorine. It On opening the tubes under mercury, no-or only a very requires costly plant without accomplishing the required minute quantity of-gas was found to have been produced, object-a perfect regeneration of the manganic oxide. An the mercury almost entirely filling the remainder of the improvement on this process, although not industrially tube not occupied by the liquid benzol.

available, was that of Clemm* who substituted carbonate The benzol distilled entirely away between 80° to 81° of magnesia for chalk. From the magnesium chloride without leaving any residue.

formed by the decomposition of the manganese chloride Potassium in the presence of finely-divided silver had he liberated hydrochloric acid by means of superheated no more effect than the sodium alone.

steam, whilst the magnesia simultaneously formed was Zinc, or the copper-zinc couple, is also without action again applicable for the precipitation of fresh quantities at temperatures up to 150° C.

of manganese solutions. This method, therefore, proIt was found unsafe to continue the action of sodium vided for the regeneration of the chlorine united with the at temperatures niuch higher than 250° C., several violent manganese, which in Dunlop's original process was lost explosions taking place, probably owing to the action of in the almost useless form of chloride of calcium. A the fused sodium on the glass.

method of regenerating manganese, very advantageous

under certain circumstances, has been devised by P. W. II.

Hofmann, and has been successfully introduced in the If clean pieces of sodium or potassium be warmed works at Dieuze, and in certain German establishments. under benzol in which phosphorus is dissolved, or pieces The inventor combines the regeneration of manganese in of sodium and phosphorus heated gently together under a successful manner with that of sulphur.t Hofmann benzol, the surface of the metal becomes covered with a precipitates the solution of manganese with the yellow brilliant red film of amorphous phosphorus, which adheres polysulphides of calcium obtained by the lixiviation of very closely and prevents further action.

vat-waste after prolonged exposure to the air. The manThe same action takes place in the cold, the film ap- ganese sulphide thus obtained, containing 57'5 per cent pearing at first yellow. It forms very rapidly on boiling, of sulphur, is burnt, a part of the sulphur being recovered when the red substance on its first formation has the ap. as suiphurous acid and conducted into the chambers. The pearance of melting on the surface of the containing residue is heated with nitrate of soda (1 mol. to 1 atom of vessel.

manganese in the residue), and thus converted into a No metallic phosphide is formed at temperatures under higher oxide of manganese, which is then transferred to 100° C., and the benzol is not affected.

the chlorine stills as a manganese of 55 per cent.

Oxides W. R. H. of nitrogen are evolved at the same time, which, with the Royal College of Chemistry,

aid of water and air, can be condensed as nitric acid. The South Kensington, July, 1876.

peroxide thus obtained consumes, indeed, 2 to 3 per cent more hydrochloric acid than native manganese, but is

much more readily soluble. REPORT

Passing over other attempts at the same object, we may mention, as a curiosity, one process which proves, at

least, how intense has been the desire to regenerate manDEVELOPMENT OF THE CHEMICAL ARTS ganese. Esquiron and Gouin make the ingenious proDURING THE LAST TEN YEARS.* posal to revivify manganese residues for the preparation

of chlorine by means of chloride of lime! By Dr. A. W. HOFMANN.

(To be continued.) (Continued from p. 5.)

ON THE

as

to

Chlorine, Bromine, Iodine, and Fluorine.

ON MEASURING AIR IN MINES. I
By Dr. E. MYLIUS, of Ludwigshafen.
Chorine and Chloride of Lime.—By far the larger

By JOSEPH DICKINSON, F.G.S., portion of the hydrochloric acid evolved in Leblanc's

H.M. Inspector of Mines. soda process is utilised in the preparation of chlorine

an intermediate product in the manufacture of Anemometers, or air-meters as they are often called, are chloride of lime. As is well known the native per

now in common use for measuring the velocity of airoxide of manganese (pyrolusite) has long been employed currents in mines. Forty years ago they were seldom seen. for this purpose. As long as this mineral was

The methods then practised are described in the well known be found in sufficient quantity there was no occasion report prepared by Mr. James Mather, Honorary Secretary to seek out any substitute. By degrees the manganese

of the South Shields Committee appointed in the year mines became less productive, the samples in the market 1839 to investigate accidents in mines. They were by grew poorer in the effective ingredient, peroxide of man

the smoke of gunpowder or tobacco, and the regulated ganese, and the prices became higher. Hence, on the pace of a person by the flame of a candle. No mechanione hand, experiments became necessary to re-convert the cal appliance arpears to have been in use. The report chloride of manganese-the residue from the production refers to an anemometer constructed by Mr. Thomas of chlorine-into peroxide, in order thus to reduce the Elliot (a brother of the present baronet, Sir George) in 1835, outlay for maganese and to bring back a useless and when an overman of Pensher Colliery, which worked by troublesome residue into industrial circulation ; on the "the air acting on four wands similar to a windmill, which other hand, attempts were made to produce chlorine with- met so strongly with the approval of the coal-owners that out the intervention of manganese.

in that year, at their meeting at Newcastle-on-Tyne, they The first procedure for the regeneration of manganese presented him with ten guineas for his invention, but they from its residues which has met with a practical applica- did not adopt it in one of their mines." tion is that of Dunlop ; the chloride of manganese being

* Clemm, Dingl Pol. Journ., clxxiii., 128.

+ Compare Dr. F. Tiemann's remarks on the utilisation of soda *"Berichte über die Entwickelung der Chemischen Industric residues in a subsequent part of the present report. Während des Letzten Jahrzeaends."

* A Paper read before the Manchester Geological Society,

26
Measuring Air in Mines.

{ , .

July 21, 1876. The first anemometers which appear to have come into , Dr. Prestell, is described by Messrs. Negretti and Zambra, general use in mines were those of M. Charles Combes, of of London, in their illustrated catalogue for 1873. Paris, and Mr. Benjamin Biram, of Wentworh, Yorkshire, Mr. William Peace, of Wigan, also patented an anemo. both being similar in principle to Mr. Elliott's. M. Combes, meter about twenty years ago, the moving power being in his valuable work, “ Traité de l'Exploitation des Mines, from the action of air on a block of wood hung in the 1844;" refers to a description of his anemometer written downcast shaft, srom which, by means of a wire or cord, by him in the Annales des Mines, by which it appears that motion is given to a finger on a dial-plate above ground. his anemometer was introduced in 1837. Mr. Biram's The foregoing anemometers are apparently the principal anemometer, it seems by the patent specification, was ones which have as yet been proposed for or actually used sealed August 3, 1842, the scope of it being for registering in mines. A variety of others, however, some of ancient the velocity of bodies propelled through water or wind date, have been used for measuring the wind on the and employment for paddle-wheels, stern-propellers, and surface. other rotary engines. M. Combes's instruments seem to The first anemometer of which there appears to be any have been made by M. Newman, of Paris, and Mr. Biram's record is attributed to Dr. Croune, in 1667, which, it is by Mr. Davis, of Derby.

said, did not answer the purpose intended. Better instruRobinson's anemometer, consisting of four revolving ments seem to have been invented by other scientific men hemispherical hollow cups fixed on four arms radiating | during the last century. The modes of action comprised from a centre (as commonly used on observatories), have the compression of a spiral spring, the elevation of a as yet been but little used in mines. It appears by weight round a centre ading at the arm of a variable lever, F. Pastorelli and Co.'s work on standard instruments, and a bag of air communicating with a glass tube, in the form by other authorities, that this anemometer was invented of a lengthened U, being sometimes substituted for the by Dr. Robinson, of Armagh, and that it was used in tidal spring. An anemometer by Leslie depended on the and meteorological observations on the coast of Ireland principle that the cooling power of a current of air is equal in 1850. It is also stated that Dr. Robinson, after a series to its velocity. Another instrument depended upon the of carefully conduced experiments, found that these cups evaporation of water, the quantity evaporated being profixed upon a vertical axis travel at the rate of one-third of portional to the velocity of the wind, varying, however, that of the wind, and that this law exists irrespectively of one would suppose, according to the dryness of the wind. the size of the cups or the length of the arms.

Wolfius's anemometer, as described by him in 1746, Another combination of the windmill anemometer has consisted of four sails similar to those of a windmill, but recently come into use in mines. The arrangement is smaller, turning on an axis. On the axis is a perpetual attributed to Dr. Parkes, F.R.S., for whom it is said to screw, which turns a vertical cog.wheel round a second have been originally made by Mr. Lowndes, a working axis. To the second axis is attached a bar on which a instrument maker in London. This instrument is some weight is fixed, so that the sails cannot turn without times known as the Casella or Casartelli anemometer. moving round ths bar in a vertical circle. When the wind

All windmill anemometers, it will be understood, acts upon the sails the bar rises, and this continues until require timing, and also correction, in order to ascer the increased leverage of the weight furnishes a countertain the true velocity of the air from the number of revolu. poise to the moving force of the wind. It also appears to tions.

have acted by winding up a weight. Anemometers, " a mere inspection of which would en- Regnier's anemometer indicated the pressure upon a able an officer to ascertain in an instant the exact velocity dial-plate, the moving power being a flat wooden surface of the air, without the necessity of timing or correcting," on which the air acted, pressing it into a box with springs have long been known, but the only one that I know of and mechanism. as being in use in mines, is the one devised by myself The anemometers of Dr. Whewell and Mr. Osler are about twenty-five years ago, which is known as the Dickin- descrited in Sir W. Snow Harris's report to the British son anemometer. By means of this the velocity of the Association, in 1841-44. That of Dr. Whewell was by air may be read off at a glance. It consists of a light, means of a windmill Ay, which worked an intermediate counterpoised, flat fanplate, which is usually made of train of wheels and caused the varying pressure to be talc, and hung upon two fine bearings, so as to be easily marked on a fixed cylinder. Mr. Osler's traced the direcmoved by the air current. Alongside of the fan-plate tion of the wind and its pressure on a given area, which there is a quadrant, graduated and figured--the figure up was moved by clock mechanism. An invention by the to which the fan-plate is blown being the velocity of the Rev. W. Foster is also described as ingenious. air, in feet, per minute. There is also a spirit-level for Lind's anemometer, which is an inverted glass syphon setting the instrument level. In using this instrument all in the form of a U, is described in the Philosophical that is requisite to ascertain the number of cubic feet of Transactions, 1775. An improvement of this has been air passing per minute is to multiply the velocity indicated made by Sir W. Snow Harris, who, by reducing one of by the anemometer into the area in feet of the place where the limbs to the diameter of one-fourth of the tube which the observation is taken. These anemometers have been is open to the wind, and by making the first part of the made only by Mr. Casartelli, of Manchester.

scale horizontal, has greatly increased the delicacy of the A modification of the Dickinson anemometer, which I instrument. He also put a plumb on it, and a light vane, have seen permanently fixed in the Bardsley Colliery, to facilitate observation. Ashton-under-Lyne, by Mr. George Wild, has the counter- As a water-gauge or manometer, the inverted glass poise made of a balance weight, which is worked by a syphon, known as Lind's anemometer, is identical with chain over a pulley. For a fixture, like this, the chain what is now commonly used in mines for measuring the and weight counterpoise appears to be an improvement, pressure of air. The water-gauge introduced a few years as the fri&tion of the links of the chain over the pulley ago by Mr. John Daglish, formerly of Hetton Colliery, imparts steadiness to the fan-plate, and thus enables Durham, is on the same principle. the average velocity to be better read in intermitting M. E. Péclet, in his valuable " Traité de la Chaleur, currents.

Paris, 1860,” says, that in 1820, M. Kallsténius employed About the same time as the introduction of the Dickinson a mill with twelve wands to measure the force of the air, anemometer, Mr. John Phillips, of Cornwall, devised a and he describes M. Combes's anemometer. He also similar instrument, except that, as I understand, it had no refers to a novel one by M. Morin, somewhat the same as counterpoise.

M. Combes's. Also to the apparatus by M. Van Hecke, M. Devillez has also introduced one on the same by which the ventilation is registered. Likewise to other principle, but with a hollow cylindrical cup instead of the instruments; in one instance by means of the air acting fan-plate.

upon the surface of a body attached to one end of an arm Another, with a flat plate suspended by two rods, by working over a centre, there being a pointer at the other

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