46

But the black rain was not the only startling phenomenon. Immediately after it fell the sea floated to land, and left stranded along the shore, vast quantities of pumice-stone, some fragments of which weighed as much as half a pound.

Whence could these and the soot and sulphur have come? That is the question which the Rev. Mr. Rust sits himself down to answer, and after investigating several theories propounded, finally connects the phenomena with an eruption of Vesuvius which happened two days before they occurred. To go further into the matter would be to deprive our readers of some of the pleasure of reading a well-written, amusing, and instructive little book, to which, therefore, we refer them for the full narrative and, to our mind, conclusive reasoning of the author.

"A Contribution to the Knowledge of Coniine," by Wertheim, details an elaborate determination of the vapour density of Azoconhydrin H1N2O, and also the properties of Conylen, and some of its derivatives-bodies of small interest to our readers.

Translations of papers by Dr. Stenhouse "On NitroErythroglucin" and "On Munjeet" follow.

An account of "Some Experiments on Vegetation," by Dr. Stohmann, succeeds, the results of which show that maize is a much more exhausting crop than beans, and that after a maize crop you may safely calculate on a good yield of beans; and further, that from a soil from which you can reap no maize you may gather a rich crop of beans.

Papers by H. Hlasiwetz and Barth "On New Products of the Decomposition of Guaiacum Resin," and on a new body homologous with orcin and obtained from galbanum, we have referred to before.

Dr. Frankland's paper "On the Combustion of Iron in Compressed Oxygen' is also translated. The only other paper we need mention is a short one on the properties of cuprous chloride. This salt, it is well known, darkens when exposed to light, in consequence, says the author of this paper, of the formation of an oxysubchloride. The author gives an easy method of preparing cuprous chloride, which consists in dissolving equal equivalents of sulphate of copper and common salt and passing sulphurous acid through the solution. The cuprous chloride separates out as a white crystalline powder, which must be washed by decantation with aqueous sulphurous acid.

The Ophthalmic Review: a Quarterly Journal of Ophthalmic Surgery and Science. Edited by J. Z. LAURENCE and T.

WINDSOR. No. 2. London: Hardwicke. "ONE of the chief features in the recent progress of Ophthalmic Surgery," says one of the editors in a paper "On some Ophthalmic Instruments," "is its gradual tendency to assume the characters of the more exact sciences," which is, unhappily, more than can be said of any other branch of medical science. The object of the Ophthalmic Review is to promote this gradual tendency, and it deserves every success.

CHEMICAL NEWS,

July 23, 1864.

The Retrospect of Medicine, &c., &c. Edited by W. BRAITHWAITE, M.D., and JAMES BRAITHWAITE, M.D. Vol. xlix. January to June, 1864. London: Simpkin, Marshall, and Co. 1864.

issue of this extremely useful serial. We may content ourselves with announcing the punctual

NOTICES OF PATENTS.

Communicated by Mr. VAUGHAN, PATENT AGENT, 15, Southampton Buildings, Chancery Lane, W.C.

66

Grants of Provisional Protection for Six Months. 1533. Wilhelm August Abegg, Westminster Palace Hotel, Victoria Street, Westminster, Improvements in apparatus for distilling spirituous liquors."—A communication from Carl Falkman, St. Petersburg, Russia.

1538. William John Pughsley, Christ Church, Monmouthshire, "Improvements in obtaining sulphuric acid from the refuse 'pickle' used in tin-plate works, and also from sulphate of iron or green copperas."

1543. Thomas Ogden Dixon, Steeton-in-Craven, Yorkshire, Improvements in stoppers for bottles, jars, and similar articles, and in means or apparatus for withdrawing such stoppers from bottles, jars, and sirailar articles."

1545. James Forbes, Old Ford, Bow, Middlesex, "Improvements in the means of, and apparatus for, manufacturing sulphate of ammonia and sulphuric acid."Petitions recorded June 21, 1864.

1375. Frederick_Oldfield Ward, Hertford Street, May Fair, Middlesex, "Improvements in processes and apparatus for treating alkaliferous minerals to obtain alkalies, alkaline salts, alumina, and accessory products."-Petition recorded June 2, 1864.

"An

1523. Richard Jones, Botolph Lane, Eastcheap, improved method of preserving animal and vegetable substances."-Petition recorded June 20, 1864.

1571. Joseph Tirat, Russell Place, Fitzroy Square, Middlesex, "A new voltaic apparatus for the relief of hernia in all its forms and stages.'

1577. Archibald Turner, Leicester, and James Clark, Manchester, "Improved machinery or apparatus for vulcanising india-rubber, which machinery or apparatus is peculiarly adapted for vulcanising by the cold process, or without the application of heat."

1580. James Hinks and Joseph Hinks, Birmingham, Warwickshire, "Improvements in lamps for burning paraffin oil and other volatile liquid hydrocarbons.”— Petitions recorded June 23, 1864.

1587. George Timothy Sims and John Pendley, Shadwell, Middlesex, "A new composition for preventing and removing incrustation in steam and other boilers."Petition recorded June 24, 1864.

1599. Benjamin Franklin Stevens, Trafalgar Square, coal-oil, and other similar substances, to the purposes of Middlesex, "Improvements in the application of petroleum, heating, lighting, and obtaining motive power, and in the Simon Stevens, New York, U.S.A.-Petition recorded apparatus employed therein."-A communication from June 25, 1864.

1618.-John Augustus Bouck and Thomas Hill, Manchester, Lancashire, "An improved varnish for paper, wood, metals, or other substances, which invention is also applicable to paper and calico printing."-Petition recorded June 28, 1864.

1864.

THE chemical papers in this number are confined to a short abstract of Mr. Robbins' paper "On Oxygennesis," and another "On the Relative Atomic Volume of Undecomposed Bodies," by P. Kremers.

1669. George Phillips, Holborn Hill, London, "Improvements in the manufacture of aniline colours."Petition recorded July 5, 1864.

NEWS

Notices to Proceed.

507. William Henry Mellor, Liverpool, Lancashire, "An improved apparatus to be used when fermenting malt liquors in casks or other like close vessels."-Petition recorded March 1, 1864.

563. Thomas Gray, Mitcham, Surrey, "Improvements in the treatment of 'jute' and 'jute' cuttings."-Petition recorded March 5, 1864.

594. Nathan Thompson, Abbey Gardens, St. John's Wood, Middlesex, "Improvements in apparatus for stop ping bottles, jars, and other vessels."

668. James Carrick, George Square, Glasgow, Lanarkshire, "Improvements in apparatus for inhaling, breathing, and respiratory purposes."-Petition recorded March 16, 1864.

827. Richard John Edwards, Bow, Middlesex, "Improvements in the mode of toughening papers and other substances to render them suitable for the application of abrasive substances and for other purposes, and in apparatus used in such manufacture."-Petition recorded April 2, 1864.

1515. Thomas Agnew, jun., Manchester, Lancashire, "Certain improvements in apparatus for coating or covering moulded or other surfaces with certain composition or material."-Petition recorded June 18, 1864.

1525. Richard Smith and Christian Sieberg, Glasgow, Lanarkshire, N.B., "Improvements in obtaining colouring matters."-Petition recorded June 20, 1864.

CORRESPONDENCE.

Continental Science.

PARIS, July 21, 1864. AGRICULTURAL machinery, thanks to the far-sightedness of the present Emperor, is making great way in the provinces. The Journal d'Agriculture Pratique announces a grand trial of reaping machines to take place at Amiens, under the auspices of the Agricultural Committee of that city, towards the end of the month, so that the farmers may see what to buy for the coming harvest. Prizes in money and medals will be given.

Your readers, who, like myself, tasted Chinese mutton at one of the late banquets of the British Acclimatisation Society, will be glad to hear the Chinese ram and ewe that were presented to the French Acclimatisation Society last year are increasing and multiplying. Last July the ewe dropped four lambs. She suckled three, and the remaining one, to whom she took a most unaccountable dislike, for it was one of the prettiest lambkins ever seen, had to be brought up by hand. Last January she dropped three more, making seven altogether, all of whom are thriving. The mother is again in that condition in which Chinese ewes like to be who love their mandarins, and seems in no way to have suffered from being in a state of confinement, or, rather, I should say, captivity, for fear of being misunderstood when speaking of these very prolific creatures. Besides their fecundity, they possess the advantage of making most delicious meat, and growing wool of great fineness and length of staple:

M. Nobel announces that by damping mining powder with nitroglycerin its explosive power is trebled, and the noise of the explosion much less than when ordinary powder is used.

In order to increase still more the constancy of the Daniel's battery, Father Secchi advises the use of fine sand or of powdered sulphur in the porous cell. He accounts for its action by supposing that when the ordinary liquid alone is used there is greater liability to local action taking place upon the zinc. In a battery, the circuit of which is closed for two minutes every quarter of an hour, the learned Father has used an ordinary piece of commercial sheet zinc, half a millimetre in thickness, which has continued in action for more than six months,

without showing the least sign of corrosion. For large elements instead of porous diaphragms he uses bags made of coarse linen cloth, well anointed with a luting of flour and lime. Those who have experienced the difficulty of procuring large porous cells would do well to test these contrivances.

The Academy of Sciences at Vienna have offered a prize of 200 ducats (about 90l.) for the best research on the movements of the fixed stars. The papers are to be sent in before December 31, 1865.

The new Astronomical Society, founded last year at Heidelberg, is doing good work. Some dozen of its most eminent members are computing the disturbances which have taken place in the movements of Mercury, Venus, Mars, Jupiter, Saturn, and Uranus. Some of them go back as far as 1770. The asteroids, too, are receiving great attention from a certain number of members, each taking a planet under his observation and observing its motions periodically. The society is essentially international in its character, and numbers amongst its members not only German, but English, French, Italian, and Russian sstronomers. Unlike M. Leverrier's new society, the Heidelberg Society rejects the principle of giving prizes for competitive papers.

The experiments made by several leading sericiculturists on the eggs of the Japanese variety of silk-worms, which were brought by M. Berlandia, have for the most part been successful. Although a large number of the eggs were infertile, yet those that did hatch produced healthy worms, most of which have now attained to the cocoon stage. The experimenters in these foreigners anticipate a large crop of eggs for next year. If the sericiculturists can succeed in introducing the Japanese insect into France it will be of the utmost importance, for the spread of disease amongst the French worms has been fearful of late years. A fine crystal of the raw Elban mineral pollux has just been presented to the mineralogical department of the museum of the Ecole des Mines. This rare mineral is interesting as, according to the researches of M. Pisani, it contains a very large proportion of cæsium. Up to the time it was examined by M. Pisani, the cæsium was always supposed to be potassium or sodium. Those who possess good collections of minerals supposed to contain these two alkaline metals, should set to work and examine them by the aid of the spectroscope. The trouble taken would doubtless be rewarded by the discovery of many other minerals besides pollux containing cæsium or rubidium, hitherto taken for potash and soda.

The Duke de Luynes and his companions have just returned from visiting the Holy Land and the Dead Sea, and have brought home with them a large number of specimens and observations of the greatest interest. It strikes me that this is a much better use to which to apply ducal revenues than cultivating the friendship of firemen and engine-drivers.

A Case of Dialysation.

To the Editor of the CHEMICAL NEWS. SIR,-In preparing solutions of vegetable acids in a large manufactory lately where, as usual, the solutions are separated from an insoluble residue which is washed until tasteless, I found in one of the filters an impossibility of accomplishing this, the acid taste remaining, although water freely percolated through the mass; and on closer examination I found that the filtered liquor, which originally contained only a very small percentage of sulphuric acid, now consisted almost entirely of it, the crystallisable acid having been kept back by the precipitate, which in this case seems to have acted as a dialyser. I may further add that as soon as there was more space allowed below the false bottom, so that the liquor could not remain at all in contact with the precipitate, this effect ceased. Thinking this fact may be of interest to some of your readers, I am, &c.,

CHEMICUS.

48

Solubility of Gold.

To the Editor of the CHEMICAL NEWS. SIR, While examining an alloy of silver and gold for the purpose of ascertaining the percentage of gold that it contained, I found, to my surprise, that a mixture of sulphuric acid and nitric acid dissolves gold to a considerable extent. This fact seemed to be of some importance, and being unaware of a similar observation having been hitherto made, I send you a note of it. I am, &c., A. REYNOLDS.

MISCELLANEOUS.

SIMPSON v. HOLLIDAY.

THIS was a trial, without a jury, before Vice-Chancellor Page Wood. Substantially the case was the same as that of Simpson v. Wilson, tried before Lord Chief Justice Cockburn, in December, 1862, and fully reported in vol. vii. of the CHEMICAL NEWS. We need now, therefore, only recapitulate the leading points in the evidence.

The patent in dispute is that of Medlock for producing Magenta colour by operating on aniline with dry arsenic acid, and the case turns upon the meaning of the word dry in the specification. By dry arsenic acid is it meant the anhydrous acid containing absolutely no water, or is it the hydrated acid which is dry to the senses? The latter is the meaning contended for by the plaintiff, and the former by the defendant, who urges that, inasmuch as that anhydrous acid will not produce the colour, the patent is void.

The first witness called was Mr. E. C. Nicholson, one of the plaintiffs, who, in reply to questions by Mr. Grove, stated that he had made and sold arsenic acid before the date of Medlock's patent. He sold it in the dry state. The term dry is constantly applied to bodies which contain water; what is called dry lime contains 39 per cent. of water; dry alum may contain 50 per cent. of water. He supplied Dr. Medlock with the dry commercial arsenic acid. In making the colour he preferred to use a solution of arsenic acid, and to heat the mixture until the water of solution was driven off, and only the water of hydration left. No colour is produced as long as water is present. In his judgment there was no chemical difference between producing the colour by using water and boiling it off, and making it in closed vessels with dry arsenic acid. The chemical reaction is the same in both cases. The object of specifying dry acid was to get at something like a proper proportion of acid to use. It is a better indication of proportion.

In cross-examination by Mr. Hindmarsh, the witness stated that the process given in several books for making arsenic acid would produce the dry but not the anhydrous acid. In order to obtain the colour it was necessary to form arseniate of aniline, which could not be formed without water. Dry arsenic acid with 14 per cent. of water would probably unite with an equivalent of aniline to form arseniate. Practically he used 75 per cent. of solid arsenic acid and 25 per cent. water, which would really amount to 32 per cent. of water, and 68 of anhydrous acid. The use of water is entirely mechanical; therefore, within certain limits, the larger the quantity of water you employ, the better combination with aniline you get. 25 per cent. of water answers very nicely. Dry arsenic acid will combine with aniline; anhydrous will not. If you mix anhydrous acid, aniline, and water, the acid must first combine with the water before arseniate of aniline is formed. No colour will be produced until the water of solution has been driven off, and a temperature of about 320° is reached. A mixture of arsenic acid with 25 per cent. of water and aniline, heated in a sealed tube to 370°, produced very little colour, showing that it is necessary to get rid of the

water.

CHEMICAL NEWS, July 23, 1864.

Re-examined by Mr. Grove: The proportions we use are six gallons of aniline to four gallons of a solution of arsenic acid containing 25 per cent., which will yield about 62 lbs. of arsenic acid, and 60 lbs. of aniline. The exact proportions are not important, so long as you have an excess of aniline, that is a sine qua non.

Dr. Hofmann was next examined. He stated that the word "dry" had been loosely employed by chemists, sometimes to indicate anhydrous materials, and at other times hydrated bodies which were dry to the touch and eye. This case will introduce greater precision into the language of chemical manuals. Whether the word dry means anhydrous or not must be judged from the

"

context.

Dr. Odling examined: He said he was not misled by the use of the word "dry" in the specification. In the majority of instances when the word "dry" is used in chemical books, it simply means dry to the touch.

The remainder of the evidence for the plaintiffs is really but a repetition of the foregoing statements. On the second day an experiment was made in court to prove the colour produced in a sealed tube was very small in comparison with that formed when aniline and dry arsenic acid are heated in the open air.

For the defendant, Dr. W. A. Miller was first examined. He stated that in his own book on Chemistry "dry arsenic acid is spoken of as an anhydrous substance. Before these trials, dry and anhydrous were used as convertible terms with reference to arsenic acid. He was familiar with arsenic acid in the anhydrous form before the trial. No colour is produced by the action of anhydrous arsenic acid upon anhydrous aniline. But colour is produced when aniline and a solution of arsenic acid are heated in a sealed tube.

Mr. D. Campbell, Drs. Taylor, Letheby, and Wanklyn gave similar testimony. Evidence was also given by manufacturing chemists who had supplied or had been applied to for fused and vitrified arsenic acid by Messrs. Hands and Son, of Coventry, who held the first assignment of Medlock's patent.

The hearing of the case lasted six days.

On the 15th the learned Vice-Chancellor gave judgment in favour of the plaintiff; but we understand that the defendant has signified his intention to appeal.

ANSWERS TO CORRESPONDENTS.

In publishing letters from our Correspondents we do not thereby adopt the views of the writers. Our intention to give both sides of a question will frequently oblige us to publish opinions with which we do not agree.

and Advertisements and Business Communications to the PUBLISHER, at the Office, 1, Wine Office Court, Fleet Street, London, E.C.

All Editorial Communications are to be addressed to the EDITOR

Vol. IX. of the CHEMICAL NEWS, containing a copious Index, is now ready, price 10s. 8d., by post, 118. 2d., handsomely bound in cloth, gold-lettered. The cases for binding may be obtained at our Office, price 18. 6d. Subscribers may have their copies bound for 2s. 6d. if sent to our Office, or, if accompanied by a cloth case, for 18. Vols. I. and II. are out of print. All the others are kept in stock. Vol. X. commenced on July 2, 1864, and will be complete in 26 numbers.

A Reader. We are not aware that the substance ormulated has ever been prepared.

Dr. L. Schad.-It might answer our correspondent's purpose better, perhaps, if the mistake were not mentioned.

M. 0.-There are two volumes of the Philosophical Magazine every year, beginning in January and July, price 17s. 6d. per vol. Repertoire de Chimie, &c., one vol. a-year, beginning in January. For price ask foreign bookseller.

A Young Chemist.-1. Burn with soda lime, and determine ammonia by standard acid as described in the manual. 2. The smell is proper to the oil, and could not be removed without destroying it.