286 



NA TURE 



\jfan. 2 1, 1886 



■quisitely-preserved leaves, completely difterent in character to 

 any previously seen in the basalts. 



The new flora differs considerably from that of the shales 

 above, and very large leaves of many kinds occur in the clay at 

 the base. The leaves in the limestone are smaller and very 

 sparsely scattered through it ; there are, moreover, no cleavage 

 planes, and hence much patience is required to obtain and 

 develop them. I have obtained about twenty species of dico- 

 tyledon from it, tlie most prevalent being Grewia creimta, 

 Hr., and Corylits MacQimrrii, Forbes, and Acer arclicum, llr., 

 all of which are also found in beds of the same age in Green- 

 land. There are no ferns and only three conifers, a large 

 variety of Ginkgo adianloules, Unger. , a new Podocarpus, tlie 

 most northerly species found, and Taxtis Cainphelli. The frag- 

 ments from the clays show about eight additional species, and 

 altogether I should judge that both floras were very rich. The 

 most characteristic plants of the shales are those described by 

 the Duke of Argyll and Edward Forbes, Platanites acfroiiles 

 and Rhainnites mitlthifniis. Taxitcs Canipbdli is not, as affirmed 

 by Heer, identical \;ith Sequoia LungsJorfii, but is a true Ta.xm. 

 Other leaves are certainly referable to Prolophyllum, and we 

 have representatives of leaves determined as Alnus, Conius, 

 Berchenia, Popuhis, and Corylits — but among them there are 

 none, so far as I can ascertain, that have ever been found in 

 European beds of Miocene age. The flora seems to bear a 

 prima facie resemblance to Cretaceous floras of America rat!ier 

 than to any yet known from Europe. The resemblance of the 

 Coniferce to those indigenous to China at the present day is too 

 remarkable to be overlooked. 



It has became evident that the fluviatile rocks of the British 

 basalts are of fargreater extent and importance than had hitherto 

 been imagined. Their base is exposed at Burg Head on the oppo- 

 site side of Loch Scridain, resting upon Jurassic rocks and frag- 

 mentary masses of chalk, and is formed of two immense sheets of 

 ash, the lowest of which is full of scorix. About lOo feet ab.ive 

 these, resting upon columnar basalt, are sands and clays from 

 9 to 12 feet thick, in every respect similar to those of Ardtim 

 Head. Overlying these is a bed of rudely columnar basalt, and 

 there cannot lie much doubt about the fluviatile series on both 

 sides of the loch being upon the same horizon. The beds are, 

 in fact, seen to be horizontal to the west as far as the eye can 

 reach. The horizon of the Ardtun gravels would, therefore, 

 seem to be about 150 feet from the base of the series. Taking 

 into account the superior thickness of the basalts in Mull, and 

 above all the presence of ash-beds at their base, it seems 

 probable that they were nearer the vents than Antrim, and th.at 

 their lowest beds are at least not newer, so that the Mull leaf- 

 beds at 150 feet from the base should be much older than the 

 Glenarm and Ballypalady leaf-beds at 600 feet from the base. 



The horizontal extent of the fluviatile beds of Mull is more 

 difficult to estimate. Gravels and fluviatile beds exist in many 

 localities, and black shales, with identical leaves, have been 

 found in Canna, and leaflets of Taxus or a similar foliaged 

 conifer at Uig. 



A very interesting relic of the Eocene vegetation occurs at 

 Burg, for a large tree, with a trunk 5 feet in diameter, has 

 been enveloped as it stood to a height of 40 feet, by one of the 

 underlying lava-beds. Its solidity .and girth enabled it to re-ist 

 the fire, but it subsequently decayed, leaving a hollow cylinder 

 filled in with debris, and lined apparently with the charred 

 wood. There is also the limb of a larger tree in a fissure not 

 far off. The wood proves to be coniferous, belonging possibly 

 to the Podocarpus, whose leaves are so conspicuous in the beds 

 above. 



Mathematical Society, January 14. — Mr. J. W. L. 



Glaisher, F. K.S., President, in the chair. — Mr. J. B. Colgrove, 

 Loughborough Grammar School, was elected a Member, and 

 Mr. S. O. Roberts was admitted into the Society. — Mrs. 

 Bryant, D.Sc, read a paper on logarithms in general logic. An 

 animated discussion followed between the author and Mr. 

 Kempe, F.K.S., in which Prof .Sylvester, the President, and 

 Mr. S. Roberts, F. R.S., also took part.— Mr. J. Hammond 

 (Prof Sylvester in thec'-.air) read a paper on a class of integrable 

 reciprocants (see report of Prof. Sylvester's Oxford lecture in 

 Nature, January 7, p. 222). — Capt. Macmahon made a short 

 comiuunication also bearing on reciprocants. 



Chemical Society, December 17, 18S5.— Dr. Hugo Miiller, 

 F.R.S., President, in the chair. — Tlie following circular letter 

 was read by the Secretary : — 



Elizabeth Thompson Science Fund. — This Fund, which has 

 been established by Mrs. Elizabeth Thompson, of Stamford, 

 Connecticut, " for the advancement and prosecution of scientific 

 research in its broadest sense," now amounts to 25,000 dollars. 

 As the income is already avail.able, the trustees desire to receive 

 applications for appropriations in aid of scientific work. This 

 endowment is not for the benefit of any one department of 

 science, but it is the intention of the trustees to give the prefer- 

 ence to those investigations, not already otherwise provided for, 

 which have for their object the advancement of human know- 

 ledge, or the benefit of mankind in general, rather than to re- 

 searches directed to the solution of questions of merely local 

 importance. 



Applications for assistance from this fund should be accom- 

 panied by a full statement of the nature of the investigation, of 

 the conditions under which it is to be prosecuted, and of the 

 manner in which the appropriation asked for is to be expended. 

 The applications should be forwarded to the Secretary of the 

 Board of Trustees, Dr. C. S. Minot, 25, Mt. Vernon Street, 

 Boston, Mass., U.S.A. 



The first grant will probably be made early in January, i 886. 



(Signed) H. P. BOVVDITCH, President. 



\Vm. Minot, Jun., Treasurer. 

 Francis A. Walker. 

 Edw. C. Pickering. 

 Charles Sedgwick Minot, Secretary. 



The following papers were read : — The action of steam on 

 carbonic o.xide, by H. B. Dixon. The action of steam in deter- 

 mining the union of carbonic oxide anrl o.xygen has been 

 explained by the author as leading to an alternate reduction and 

 oxidation whereby the hydrogen conveys the oxygen to the car- 

 bonic o.xide:— (i) Co-MLO = C02H- H^ ; (2) 2H.,-f 0. = 2H.p. 

 This explanation has been rejected by Moritz Traube {Bcr., 18S5, 

 p. 1S90) on the ground that carbonic oxide does not decompose 

 steam at a high temperature. Traube represents the influence 

 of steam as consisting in the formation from it of peroxide of 

 hydrogen, which oxidises carbonic oxide, steam being re-formed. 

 The author has already shown that steam is decomposed by 

 carbonic oxide at a high temperature, for when carbonic oxide is 

 exploded in presence of steam with insufficient oxygen to com- 

 pletely burn it, the carbon dioxide formed is more than double 

 the oxygen, and hydrogen is found in the residue. Horstmann 

 arrived at the same conclusion. When sparks are passed 

 through a mixture of steam and carbonic oxide, carbon dioxide 

 and hydrogen are formed until a certain fraction (which varies 

 with the nature of the spark) of the carbonic oxide is turned into 

 carb^ dioxide. When sparks are passed through a mixture of 

 carbon dioxide and hydrogen, carbonic oxide and steam are 

 formed until a certain fraction of the carbon dioxide is turned 

 into carbonic oxide. In neither case is the reaction complete. 

 An equilibrium is reached when about 10 per cent, of 

 carbon dioxide is present to 90 per cent, of carbonic oxide. 

 By the prolonged passage of the sparks a considerable quantity 

 of formic acid is produced. When a coil of platinum wire is 

 heated to redness in steam and carbonic oxide, carbon dioxide 

 and hydrogen are formed until from 10 to 15 per cent, of the 

 carbonic o.xide has been oxidised. Similarly, when a coil of 

 platinum wire is heated in carbon dioxide and hydrogen, car- 

 bonic oxide and steam are formed until the corresponding limit 

 is reached. No formic acid is produced. When a coil of wire 

 is maintained at a red heat in a mixture of carbonic oxide .and 

 steam, and the carbon dioxide formed is removed by means of a 

 dilute solution of potash, the carbonic oxide is in time com- 

 pletely oxidised to carbon dioxide with the liberation of the cor- 

 responding volume of hydrogen. Similarly, when a coil of 

 platinum wire is maintained at a red heat in a mixture of carbon 

 monoxide and hydrogen, and the steam formed is removed by 

 means of phosphoric oxide, the carbon dioxide is in time com- 

 pletely reduced to carbonic oxide. Since these experiments 

 were made Naumann has shown that when carbonic oxide and 

 steam are heated in a tube to 950°, io'5 per cent, of carbonic 

 o.xide is turned into carbon dioxide. — On multiple sulphates, by 

 Miss E. Aston and S. U. Pickering. — On the use of ferrous 

 sulphate in agriculture, by A. B. Griffiths, Ph.D. — On phenyl- 

 tribromomethane, C6H5.CBr3, by Walter II. Ince. 



Institution of Civil Engineers, January 12. — Sir Frederick 

 J. Bramwell, F.R.S., President, in the chair. — The paper read 

 was " On Gas Producers," by Mr. Frederick John Rowan. 



