Relation of Orders of Reptiles to Strata.-Professor Cope, who has already so much distinguished himself upon American palæontology, gives in a recently-published memoir the following tabular arrangement of this class, as regards its rocks, which contains these remarks: Present Time-Rhynchocephalia; Crocodilia; Testudinata; Lacertilia; Ophidia. Pliocene-Crocodilia; Testudinata; Lacertilia; Ophidia. Miocene-Crocodilia; Testudinata; Lacertilia; Ophidia. Eocene.-Crocodilia; Testudinata; Lacertilia; Ophidia. Cretaceous. Ornithosauria; Dinosauria; Crocodilia; Sauropterygia; Testudinata; Lacertilia; Pythonomorpha.

The Geology of Salt-Lake City.—Mr. W. P. Blake has written a letter to Professor Silliman in which he describes briefly, but pretty generally, the geology of the Salt-Lake City. He says that he left New Haven hurriedly to reach the Emma Mine and examine it. It is a remarkable mine. Within a little more than a year it has yielded ore worth over $2,000,000, and this without any special outlay. It is a great mass of soft earthy-looking ore, the result of the decomposition of argentiferous galena. It is dug out with shovels and picks, sacked, and sent to Liverpool, where it sells for about $175 per ton. The mass is between strata of limestone, the middle members of a series of strata over a mile thick. The lower members are slate and quartzite, and rest upon the immense masses of syenitic granite which form the picturesque Alpine-like peaks of the Wahsatch. These strata are all much uplifted and contorted, some of the harder beds surging up into peaks at least 11,000 feet above tide. The mine is at an elevation of 8,500 to 9,000 feet. At the head of the cañon upon the side of which it is situated, there is a fine exposure of syenitic granite for about a mile, with rounded polished backs—roches moutonnées-probably 9,000 feet above tide. These rocks give conclusive evidence of the former existence there of a large glacier. Much of the polish upon the surface has been removed by the action of the weather. The patches that remain are dark brown in colour, while the syenite is light grey, and they show the same peculiar scale-like crusts seen on the partly weathered glaciated surfaces above the Yosemite.

Geology of the Rocky Mountain.-" Harper's Weekly," an American literary journal, gives the following account, which may be of interest to our readers. The geological expedition to the Rocky Mountain region under the charge of Dr. Hayden, after completing the survey of the Yellow Stone Valley, left Fort Ellis on September 5, passing down Gallatin Valley to the Three Forks, and thence by the Jefferson to its very source, exploring many of its branches, and pursuing a direction nearly parallel to that which the party had traversed in the June previous. The valleys of the Gallatin, Madison, and Jefferson Forks of the Missouri, with all the little branches, were found occupied by industrious farmers and miners-a contrast quite striking to the doctor, who, twelve years ago, in exploring that same region, met with not a single white inhabitant. The Rocky Mountain Divide was crossed at the head of Horse Plain Creek, from which the party passed over into Medicine Lodge Creek, following this down into the Snake River Plain.

Results of the Coal Commission.-This important Commission, which has been sitting for some years, has just published the first volume of its Report.

The English coal-fields are, of course, most especially dealt with—the Scotch coal-fields being somewhat briefly treated by Mr. J. Geddes, and those of Ireland by Professor Hull. The vast amount of practical information contained in this the first volume of the Report, shows at once the great value of the results which have been brought about by the Coal Commission. We learn that we have an accessible supply of coal that will last about 276 years, but after that the coal that will remain could never be worked except under conditions of scarcity and high price. As we approach this exhaustion, the country will by slow degrees lose the advantageous position it now enjoys in regard to its coal supply; for although other countries would undoubtedly be in a position to supply our deficiencies, it may well be doubted whether the manufacturing supremacy of this kingdom can be maintained after the importation of coal has become a necessity. It is to be regretted that the Commission express rather an adverse opinion as to the finding new coal formations, &c.

The Foraminifera of the Chalk of Gravesend and Meudon.-Professor Rupert Jones and W. K. Parker, M.D., F.R.S., have been publishing some work together, with a review of Professor Ehrenberg's researches on this subject; this paper is of peculiar value, but is too technical for further abstract.-Geological Magazine, November.

Death of Sir R. Murchison.-Geology has sustained a severe loss-a loss indeed which it would be difficult to calculate-in the death of Sir Roderick Impey Murchison. Although at the ripe age of eighty years, it is a loss which geologists and geographers are alike called upon to mourn. "In relation to both these sciences, he has for many years justly occupied the most prominent positions. But, apart from his high social and scientific standing, he was a man full of genial and kindly feeling, who could be readily approached; and those who knew him most intimately acknowledge that he was never known to fail his friends in the hour of need, but was ready to aid them with his advice, his influence, and his purse, as many a young scientific man amongst us can testify. Born at Tarradale, in Ross-shire, he receive his early education as a boy at the Grammar School at Durham.” The work that he has done is enormous; the titles alone occupying several pages of the "Geological Magazine."

The Irish Coal-measures.—Mr. G. H. Kinahan, of the Irish Survey, read a paper on this subject before the Royal Geological Society of Ireland. This communication was a reply to a statement made before the Society in January last, in a paper "On the Ballycastle Coal-field," by Mr. E. Hull, in which it is asserted that there were true coal-measures in Connaught, while none exist in the provinces of Munster or Leinster, as laid down in the Geological Maps published under the direction of the late Mr. J. B. Jukes. The author of this paper showed that the coal-measures of Leinster, Munster and Connaught, were identical; therefore, if Mr. Hull's statement respecting Connaught was correct, his assertion as to Munster and Leinster must be wrong. He pointed out that the late Mr. Foot and himself wished to divide the coal-measures into four series, but that the late Mr. Jukes objected, and stated, "If we were to seek to force these coal-measure series into a strict analogy with those of other districts, we might look upon these lower black shales with marine fossils as the representatives of the upper limestone shale

of Derbyshire; and the set of sandstones and flagstones No. 2 as the representative of the millstone grit of that county. It would, however, be impossible in the south of Ireland to draw any recognisable boundary subdividing the coal-measure series, and the attempt would, therefore, only tend to confusion." The author next pointed out that palæontologically the coalmeasures of Kilkenny, Queen's County, Limerick, Clare, Kerry, &c., were similar to those of Coalbrookdale, Staffordshire, and other places in England.

The Geology of Clermont, Auvergne.-Mr. R. G. Symes, F.G.S. (Royal Geological Society of Ireland), has published an account of his enquiries in this district during the summer of 1870, when he visited the district in company with Mr. Leonard. The paper describes the result of their observations on the plutonic, aqueous, and volcanic rocks. The country chiefly examined was that between four and five miles west of Clermont. The granite is described as generally consisting of two micas (margarodite and lepidomelane, the latter predominating in nearly every case over the former), one felspar (oligoclase), and the other glassy quartz. It was found to decompose the more readily as it approached volcanic rocks. The aqueous rocks, of Upper Eocene or Miocene age, are briefly described as consisting of grits, marls, and indusial limestone or travertin. The grits are for the most part composed of the débris of granite and basalt, bound together by a siliceous cement. Mr. Symes obtained a specimen containing a well-rounded pebble of basalt: a fact of some importance, as Scrope and Lyell remark that no traces of volcanic rocks occur in these beds. In regard to the volcanic phenomena, the inferences drawn are: that the condition to which the volcanos are referable is that in which eruptive paroxysms of intense energy alternate with lengthened periods of complete inertness; that the cinder cones, domitic hills, and recent lavas, are all due to one violent paroxysm spread, over an area twenty miles long by two broad; that the presence of two such different rocks as basalt and trachyte, in close juxtaposition, can only be accounted for on the supposition that the rocks from which they are derived, namely hornblende rock and some highly felspathic rock (such as granite), were in contact prior to their being reduced to the forms we now find them in; that the granite plateau was very much in the same condition prior to the deposition of the lacustrine strata, as it is now; that prior to the deposition of the lacustrine strata this district was probably the seat of volcanic eruption.

Life of Professor J. Beete Jukes, M.A., F.R.S.-The life of this eminent geologist has been prepared by the loving hands of his sister. It possesses an excellent portrait, and extends over about six hundred pages. It is full of matter interesting to geologists and to those who were acquainted with Professor Jukes, but of course we cannot abstract it here. It is published by Chapman & Hall.

A new Fish, Phaneropleuron elegans, has been discovered by Professor Traquair, of Dublin, and is described by him in the "Geological Magazine " for December. It seems to be a fish very closely resembling the Phaneropleuron Andersoni of Huxley, but differing from it in its smaller size, in its somewhat more slender form posteriorly, in the smaller depth of the lower lobe of the caudal fin, and apparently also in the greater extension forwards

of the dorsal fin. As it is evidently at least specifically distinct, he proposes to bestow on it the title of Phaneropleuron elegans. The genus Phaneropleuron is thus common to the Upper Devonian and Lower Carboniferous formations. It is one of the most interesting of the Paleozoic Ganoids, as showing the intimate relations subsisting between the ancient Crossopterygians with acutely lobate pectorals and ventrals, and the remarkable recent types Lepidosiren, Protopterus, and Ceratodus. One cannot fail to be struck, as Professor Huxley has already indicated, with the many points of resemblance which this genus bears to Lepidosiren, in the general form of the fish, in its thin circular scales, and in many points in the structure of its internal skeleton. But from the true Dipnoi, with which Dr. Günther now unites the true Devonian Dipterus, and the carboniferous Ctenodus, it differs, as is well known, materially in its dentition; and the position of the nasal openings, so peculiar a character in the recent Dipnoi, and in the fossil Dipterus, as Günther has pointed out, remains yet to be definitely settled. Phaneropleuron must therefore remain, as Professor Huxley has placed it, the type of a distinct subfamily of Crossopterygidæ, viz., Phaneropleurini, and not very far removed from Holoptychius, and other acutely lobatemembered cycliferous Ganoids of Palæozoic times.

Death of Mr. Chas. Babbage, F.R.S.-Although Mr. Babbage was more of a mathematician than a biologist, still we may notice his death in these pages, because he did, many years ago, some good work in geology. He was born December 26, 1792, and died at his residence, Dorset Street, Marylebone, on the 20th Nov., in his eightieth year. He was the inventor and partial constructor of the famous calculating engine or machine, which the world has associated with his name, and which is now preserved in the Museum of King's College, London. As a writer in the "Dictionary of Universal Biography" remarks: "The possibility of constructing a piece of mechanism capable of performing certain operations on numbers is by no means new; it was thought of by Pascal and other geometers, and more recently it has been reduced to practice by M. Thomas, of Colmar, in France, and by the Messrs. Schütz, of Sweden; but never before or since has any scheme so gigantic as that of Mr. Babbage been anywhere imagined." His achievements, says the "Times," were twofold; he constructed what he called a Difference Engine, and he planned and demonstrated the practicability of an Analytical Engine also.

Relics of the Carboniferous and other old Land Surfaces.-Mr. Henry Woodward, F.G.S., F.L.S., has contributed to the "Geological Magazine for November an admirable essay on this subject. It is far too long for an abstract, but it will well repay a perusal. It deals with an immense multitude of facts, which are most admirably arranged together.

MECHANICAL SCIENCE.

Mr. Bessemer's Gun.-Mr. Bessemer has been directing his attention to the subject of heavy ordnance, and has matured some very novel and ingenious plans, which he proposes to put to the test of experiment. The great difficulty with heavy ordnance is the enormous initial pressure gene

rated by the explosion of the powder, a pressure which may reach 60,000 lbs. per sq. in. This can be modified to some extent by the use of large grain or pebble powder, which burns more slowly than powder of finer grain. Mr. Bessemer, however, proposes to secure any required reduction of the initial pressure in another way. Instead of having a single large charge of powder, he proposes to have a series of 20 to 100 smaller charges, ignited successively as the shot travels along the bore of the gun. But this sucsessive ignition of the powder would be less efficient than the explosion of a single charge in propelling the shot, unless means were taken to keep the shot under the action of the powder-gas for a longer period than in an ordinary gun. Hence Mr. Bessemer proposes to increase the length of the gun to 50 feet. By these two changes, Mr. Bessemer is said to hope to propel shot, the weight of which may be measured by tons, not by pounds. Mr. Bessemer's gun, illustrated in "Engineering," September 15, consists of inner tubes of welded wrought-iron, strengthened by steel rings, shrunk on with suitable initial tension. The gun is made in lengths, connected by flanges. The cartridge-chamber is chambered, and the charges may be successively ignited by fusees, or by means of electricity. Further, Mr. Bessemer suggests that rotation may be given to an elongated shot, not by rifling, but by the reaction of jets of powder-gas issuing from tangential orifices at its circumference. The powder-gas is supplied by a charge of powder burning in its interior, and the rotation is caused by the reaction of the jets, on the same principle as the rotation of Barker's mill or the Scotch turbine.

Wood-engraving by Machinery.-A process for engraving on wood by the cutting action of a sand-blast, is described in the "Journal of the Franklin Institute." A photographic copy of the drawing or object to be engraved is formed on a suitable matrix. This is then acted upon by a jet of sand, the particles of which have a very high velocity, so as to cut away to varying depths the surface of the block. The block is then electrotyped, and the engraving is printed from the electrotype. For various cutting and polishing purposes, the sand-jet seems likely to prove extremely valuable.

Gunpowder Gauges.-M. le Commandant de Reffye has used a form of gauge for determining the pressure in the bore of large guns, the principle of which has been suggested by M. Tresca's experiments on the flow of solid bodies. A block of lead is placed in a cylindrical hole bored into the gun, and is supported behind by a steel block through which a smaller cylindrical hole is bored. When the pressure acts on the lead, it forces it in part into the cylindrical cavity behind, and the volume of lead thus forced in forms a measure of the pressure in the bore of the gun.

St. Gothard Railway.—It is said that the St. Gothard Railway, with a tunnel about as long as the Mont Cenis tunnel, will be commenced very soon, and that the Mont Cenis staff will be transferred to undertake its construction.

Flow of Liquids.-Canon Mosely in the "Philosophical Magazine," and Professor Colding in the "Copenhagen Transactions," have been investigating the laws of the motion of water in pipes, conduits, &c. The generally accepted formulæ are known to be defective. They are founded on the assumption that the water moves in plane layers at uniform velocity.