Report of the ... Meeting of the British Association for the Advancement of Science

in 189 fathoms, and also a fragment sent to me to examine by Mr. D. Robertson, who procured it from Faroe, which exactly correspond with Fleming's brief description; and as the specimens which I have seen are from the north and from-the south of Shetland, there is every likelihood of its having been found at the intermediate locality. A description of the species will be given by me in the Report of the Invertebrata procured in the Lightning' expedition.

Report on the Chemical Nature of Cast Iron.-Part I. Account of some Experiments made to obtain Iron free from Sulphur. By A. MATTHIESSEN, F.R.S., and S. PRUS SZCZEPANOWSKI.

FOLLOWING out the plan indicated in the preliminary report presented to the Association in the year 1866, we have been endeavouring to prepare pure iron, but have encountered greater difficulties than we expected, owing to the great affinity which iron has for sulphur. Although we have not been able as yet to prepare iron absolutely free from sulphur, yet the results, as far as they have been obtained, may be of interest to the Association, and a brief account of them is given in the following pages.

In the endeavour to prepare pure iron, we always found sulphuretted hydrogen on dissolving the metal in dilute hydrochloric acid. The small quantity of sulphur contained in the iron did not proceed from the hydrogen or from the platinum-tube in which the oxide was reduced. The manner of preparing the pure hydrogen and the precautions taken with the platinumtube will be described hereafter.

The first series of experiments were made by precipitating the hot, concentrated, clear solution of protosulphate of iron by oxalate of ammonium, washing the precipitate till the wash-waters no longer indicated sulphuric acid with chloride of barium, heating the dried oxalate of iron to redness in a platinumdish, and reducing the oxide thus obtained in a platinum-tube. The reduced iron contained sulphur. In all the experiments we describe sulphur was tested in the following manner. The iron was placed in a test-tube with some dilute pure hydrochloric acid, and the gases were allowed to pass through a small tube fitted into a cork in the test-tube, and to impinge on a paper moistened with acetate of lead. The evolution of sulphuretted hydrogen, after a very little experience, moreover is just as easily detected by the smell.

Experiments were also made with the oxalate of iron by redissolving it in hydrochloric acid and reprecipitating with ammonia, or by dissolving the oxide obtained by heating the oxalate of iron in hydrochloric acid, and reprecipitating again by oxalate of ammonium. In all these cases the reduced iron contained sulphur.

The second series of experiments were with iron obtained from the crystalline oxide. It is well known that when protosulphate of iron is fused with chloride of sodium, a crystalline oxide is obtained. For our experiments it was of course necessary to perform this operation in a platinum crucible, but it was found that the iron thus obtained contained a small quantity of platinum. We therefore employed instead of chloride of sodium the sulphate of sodium, and obtained an oxide which, after being thoroughly washed and reduced, gave an iron containing no platinum but still traces of sulphur. Experiments were then made by dissolving the crystalline oxide in pure

hydrochloric acid, and precipitating the solution by ammonia, washing the oxide, and reducing it. The iron thus prepared contained sulphur. The next experiments were made by dissolving the crystalline oxide in hydrochloric acid, digesting with chloride of barium for several days, decanting and filtering through paper (previously digested with dilute nitric acid), precipitating by ammonia (distilled from ammonia to which chloride of barium had been added), washing, and reducing the oxide. The iron thus prepared still contained sulphur.

The third series of experiments were made with sublimed proto- or sesquichloride of iron by dissolving it in water, precipitating with pure ammonia, washing, and reducing in hydrogen. All the specimens thus prepared contained sulphur. The sublimed chloride was obtained sometimes from the red oxide prepared by heating the oxalate of iron, obtained as above described, or from the crystalline oxide by dissolving it in hydrochloric acid, digesting with chloride of barium, evaporating to dryness, and subliming either in platinum vessels or in porcelain tubes, or in clay retorts, either alone or in a current of chlorine or of hydrochloric-acid gas.

In the fourth series of experiments the metal produced by either of the above methods was submitted in the platinum-tube, whilst red-hot, alternatively to the influence of hydrogen and oxygen, or hydrogen and steam, or of vapours of nitric acid and hydrogen, or of ammonia vapours, oxygen, and hydrogen. In all the cases the operation was repeated several times, and although sulphuretted hydrogen was given off during these operations, yet the iron always contained sulphur.

Further experiments were made by dissolving the purest iron in dilute acetic acid, evaporating to dryness and heating. The metal obtained still contained sulphur.

Also the iron obtained from ferrocyanide of potassium* was found to contain sulphur.

În fact we have never made or found a specimen of iron which did not contain sulphur. Even electrotype iron, said to be prepared from chloride of iron, evolved, by dissolving in dilute hydrochloric acid, a very appreciable quantity of sulphuretted hydrogen.

On the whole we have made upwards of seventy series of experiments. From the above it will be seen that we have not yet obtained a method of preparing iron free from sulphur. In fact one great difficulty is to obtain vessels which will not give up sulphur to the iron in some form or another. For instance, the platinum-tube had to be polished and boiled out with acid. every time before use. It may be mentioned that the hydrogen employed was led through the platinum-tube before reducing the oxide of iron for a quarter of an hour or more, and yielded no sulphuretted hydrogen.

Although no positive results have been obtained, we have in no ways lost hope of preparing iron free from sulphur. No doubt, on a very small scale, this might be done without much trouble; but we must bear in mind that our method must be such a one as to allow the preparation of pure iron on at least the ounce-scale.

November 1868.-The amount of sulphur contained in some specimens prepared since the Meeting of the Association amounted to only 0.001 to 0.005 per cent., the presence of the former quantity being easily detected both by the smell as well by the lead paper.

* Crystallized from a solution containing chloride of barium.

Interim Report of the Committee on the Safety of Merchant Ships and their Passengers.

As far as the Committee had been able to pursue their inquiry, it appeared that no legal regulations were in force in Great Britain affecting the loading of merchant ships; but there were regulations in force by the Board of Trade relating simply to vessels carrying passengers or emigrants, and these only related to space as bearing on the sanitary condition of such passengers, totally ignoring their safety as far as the stowage of cargo and deck-loads were concerned-the matter on which the Committee had to report. In order to carry out effectively any regulations, some precise agreement should be entered into with all the great maritime powers, and the deep draught of every vessel should be distinctly indicated by a fixed and clearly defined mark, such as a painted white ribbon extending about six feet on each side of the stem as well as stern-post (not in mid-ship), and so distinctly scribed in wooden and cut into iron ships that it could not be tampered with. When a ship was so loaded by the stern an average should not be taken, but when so loaded the load-line at that point should not be immersed. The loadline should be fixed by a government inspector. The great loss of steamers sailing from Hull had been occasioned by overloading and the shipping of successive heavy seas, the extra weight of which had caused the foundering of the vessels. Deck-loads might be carried during summer if well secured, and boats when stowed should be some height from the deck, so that the water shipped should have a clear passage. The lashings of the boats ought to be of rope, so that they could be readily cut in an emergency. Crews should be practised in the lowering of boats. The regulations thus indicated ought to apply to foreign vessels entering or leaving British ports.

Report on Observations of Luminous Meteors, 1867-68. By a Committee, consisting of JAMES GLAISHER, F.R.S., of the Royal Observatory, Greenwich, President of the Royal Microscopical and Meteorological Societies, ROBERT P. GREG, F.G.S., E. W. BRAYLEY, F.R.S., ALEXANDER S. HERSCHEL, F.R.A. S., and CHARLES BROOKE, F.R.S., Secretary to the Meteorological Society.

In the first Appendix of this Report, immediately following the Catalogue, will be found the remarks of observers on the appearance of the August meteoric shower in the current year, together with the heights of eleven shooting-stars, simultaneously observed at English stations, on the occasion of its return. In addition to these results, the heights of several meteors, simultaneously observed in recent years by Professor Heis and his assistants, are contained in the first Appendix.

Large meteors, star-showers, and aërolites have continued during the past year to attract the attention of observers, especially on the 1st, 28th, and 31st of January, and on the 29th of February last. Brief accounts of their appearance, with other observations of luminous meteors, chronologically arranged, are entered in the Catalogue; while fuller accounts of the details and attendant circumstances of the phenomena are included in the second Appendix of the Report. The same Appendix also contains a collection of accounts (chiefly extracted from foreign sources) of the August and November

star-showers in the year 1867, illustrating the brief duration and the limits of the geographical area of visibility of those showers.

The expected reappearance of the November meteoric shower in the year 1866 was such a rare occasion for careful observations that, in anticipation of its return at the appointed time, the calculations of astronomers had previously been directed to determining the real velocities and orbits of showermeteors. Of these bodies, the inquiries relating to the August meteor-ring led Mr. Schiaparelli to the remarkable discovery (which was shortly also verified in the case of the November meteors, at their reappearance) that the orbits of those meteor-groups coincide almost perfectly with the orbits of certain periodical comets. Some other investigations, of which recapitulations, owing to the number of observations of the November meteors contained in the Catalogue of the last Report, were deferred by the Committee until a more convenient opportunity should present itself for abstracting them, are contained in the last Appendix of this Report.

The entire series of charts of radiant-points, of four of which lithographed copies were last year exhibited to the British Association at Dundee, were afterwards printed, and bound together in an Atlas for distribution to observers, and to scientific persons and societies, of whose names and addresses a list is given in the same Appendix; and they were forwarded to their destinations at the close of last year. A new edition of the Meteor Atlas has since been prepared, with three new charts, and with the addition of several observations and improvements not contained in the previous Atlas. indicate the characters and positions of all the radiant-points at present ascertained to exist in the northern hemisphere, a list of the meteoric showers which it portrays accompanies the Atlas, and is inserted in the last Appendix of this Report. Some copies of the new edition having now been printed, to assist in multiplying them, the Committee contemplate offering the whole of these copies for sale to observers at the lithographer's price.

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The direction of shooting-stars in the southern hemisphere has, during the past year, been made the subject of a Memoir by Professor Heis and Dr. Neumayer. A series of nearly 2000 observations, obtained by the latter observer at Melbourne during the years from 1858 to 1863, having been submitted to examination by Dr. Heis, with a view to determining their points of radiation, thirty-nine radiant-points of shower-meteors were indicated by these researches in the southern hemisphere. Four radiantpoints of Dr. Heis's list, which is given in connexion with the foregoing list in this Report, appear to be identical with four of the seventy-seven radiantpoints observed in the northern hemisphere, leaving seventy-three separate radiant-points of meteoric showers recorded in the latter hemisphere alone. The general survey of meteor-showers, which at present extends to both hemispheres, accordingly increases the total number of radiant-points now recognized as clearly distinguishable from each other to about one hundred and twelve, or double of the number formerly reckoned in the list, as previously stated in these Reports *. For the purpose of verifying and investigating the connexion which apparently exists between certain of the radiant-points, the long duration and apparent fixity of position of others, and the dates of their maximum displays, a collection of further observations, and their regular discussion with a view to circumscribe the laws of the appearances of meteoric showers, will continue, on account of their increasing astronomical interest, to present an important subject of inquiry.

1868.

For the year 1864, p. 99.

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