to be a success, and I am glad to be able to state that Mr. Deacon has recently overcome certain difficulties in his method, and has obtained a complete absorption of the chlorine. May we hope to see oxygen prepared by a cheap and continuous process from atmospheric air? With baryta the problem can be solved very perfectly, if not economically. Another process is that of Tessier de Mothay, in which the manganate of potassium is decomposed by a current of superheated steam, and afterwards revived by being heated in a current of air. A company has lately been formed in New York to apply this process to the production of a brilliant house light. A compound Argand burner is used, having a double row of apertures-the inner row is supplied with oxygen, the other with coal gas or other combustible. The applications of pure oxygen, if it could be procured cheaply, would be very numerous, and few discoveries would more amply reward the inventor. Among other uses, it might be applied to the production of ozone, free from nitric acid by the action of the electrical discharge, and to the introduction of that singular body in an efficient form into the arts as a bleaching and oxidising agent. Tessier de Mothay has also proposed to prepare hydrogen gas on the large scale by heating hydrate of lime with anthracite. We learn from the history of metallurgy that the valuable alloy which copper forms with zinc was known and applied long before zinc itself was discovered. Nearly the same remark may be made at present with regard to manganese and its alloys. The metal is difficult to obtain, and has not in the pure state been applied to any useful purpose; but its alloys with copper and other metals have been prepared, and some of them are likely to be of great value. The alloy with zinc and copper is used as a substitute for German silver, and possesses some advantages over it. Not less important is the alloy of iron and manganese prepared according to the process of Henderson, by reducing in a Siemens' furnace a mixture of carbonate of manganese and oxide of iron. It contains from 20 to 30 per cent. of manganese, and will doubtless replace to a large extent the spiegeleism now used in the manufacture of Bessemer steel. The classical researches of Roscoe have made us acquainted for the first time with metallic vanadium. Berzelius obtained brilliant scales which he supposed to be the metal, by heating oxychloride in ammonia, but they have proved to be a nitride. Roscoe prepared the metal by reducing its chloride in a current of hydrogen, as a light gray powder, with a metallic lustre under the microscope. It has a remarkable affinity both for nitrogen and silicon. Like phos

phorus, it is a pentad, and the vanadates correspond in composition to the phosphates, but differ in the order of stability at ordinary temperatures, the soluble tribasic salts being less stable than the tetrabasic compounds. Sainte Claire Deville, in continuation of his researches on dissociation, has examined the conditions under which vapour of water is decomposed by metallic iron. The iron, maintained at a constant temperature, but varying in different experiments, from 150° C. to 1600° C., was exposed to the action of the vapour of water of known tension. It was found that for a given temperature the iron continued to oxidise till the tension of the hydrogen formed reached an invariable value. In these experiments, as Deville remarks, the iron behaves as if it emitted a vapour (hydrogen), obeying the laws of hygometry. An interesting set of experiments has been made by Lothian Bell on the power possessed by spongy metallic iron of splitting up carbonic oxide into carbon and carbonic acid, the former being deposited in the iron. A minute quantity of oxide of iron is always formed in this reaction. In organic chemistry, the labours of chemists have been of late largely directed to a group of hydrocarbons, which were first discovered among the products of the destructive distillation of coal or oil. The central body round which these researches have chiefly turned is benzol, whose discovery will always be associated with the name of Faraday. Baeyer has prepared artificially picoline, a base isomeric with aniline, and discovered by Anderson in his very able researches on the Pyridine series. Of the two methods described by Baeyer, one is founded on an experiment of Simpson, in which a new base was obtained by heating tribromallyl with an alcoholic solution of ammonia. By pushing further the action of the heat, Baeyer succeeded in expelling the whole of the bromine from Simpson's base, in the form of hydrobromic acid, and in obtaining picoline. The same chemist has also prepared artificially collidine, another base of the Pyridine series. In this list of remarkable synthetical discoveries, another of the highest interest has lately been added by Schiff the preparation of artificial coniine. He obtained it by the action of ammonia on butyric aldehyde. The artificial base has the same composition as coniine prepared from hemlock. It is a liquid of an amber-yellow colour, having the characteristic odour and nearly all the usual reactions of ordinary coniine. physiological properties, so far as they have been examined, agree with those of coniine from hemlock, but the artificial base has not yet been obtained in large quantity, nor perfectly pure.

Its

Valuable papers on alizarine have been published by Perkin and Schunk. The latter has described a new acid-the anthraflaric -which is formed in the artificial preparation of alizarine. Madder contains another colouring principle, purpurine, which, like alizarine, yields anthracene when acted on by reducing agents, and has also been prepared artificially. These colouring principles may be distinguished from one another, as Stokes has shown, by their absorption bands; and Perkin has lately confirmed by this optical test the interesting observation of Schunk that finished madder prints contain nothing but pure alizarine in combination with the mordaunt employed. Hofmann has achieved another triumph in a department of chemistry which he has made peculiarly his own. In 1857, he showed that alcohol bases, analogous to those derived from ammonia, could be obtained by replacement from phosphuretted hydrogen, but he failed in his attempts to prepare the two lower derivatives. These missing links he has now supplied, and has thus established a complete parallelism between the derivatives of ammonia and of phosphuretted hydrogen. The same able chemist has lately described the aromatic cyanates, of which one only-the phenylic cyanatewas previously known, having been discovered about twenty years ago by Hofmann himself. He now prepares this compound by the action of phosphoric anhydride on phenylurethane, and by a similar method he has obtained the tolylic, xylylic, and napthylic cyanates. Stenhouse had observed many years ago that, when aniline is added to furfurol, the mixture becomes rose-red, and communicates a fugitive red stain to the skin, and also to linen and silk. He has lately resumed the investigation of this subject, and has obtained two new bases-furfuraniline and furfurtolnidine-which like rosaniline, form beautifully coloured salts, although the bases themselves are nearly colourless, or of a pale brown colour. The interesting work of Dewar on the oxidation of picoline must not be passed over without notice. By the action of the permanganate of potassium on that body, he has obtained a new acid, which bears the same relation to pyridine that phthalic acid does to benzol. Thorpe and Young have published a preliminary notice of some results of great promise which they have obtained by exposing paraffin to a high temperature in closed vessels. By this treatment it is almost completely resolved into liquid hydrocarbons whose boiling points range from 18° C. to 300° C. Those boiling under 100° have been examined, and consist chiefly of olefines. In connection with this

subject, it may be interesting to recal the experiments of Pelouze and Cahours on the Pennsylvanian oils, which proved to be a mixture of carbolizdrogers belonging to the marsh gas series. An elaborate exposition of Berthelot's method of transforming an organic compound into a hydrocarbon containing a maximum of hydrogen, has appeared in a connected form. The organic body is heated, in a sealed tube with a large excess of a strong solution of hydriodic acid, to the temperature of 275°. The pressure in these experiments Berthelot estimates at 100 atmospheres, but apparently without having made any direct measurements. He has thus prepared ethyl hydride from alcohol, aldehyde, &c., hexyl hydride from benzol. Berthelot has submitted both wood charcoal and coal to the reducing action of hydriodic acid, and among other interesting results, he claims to have obtained in this way oil of petroleum. By the action of chloride of zinc upon codeia, Matthiessen and Burnside have obtained apocodeia, which stands to codeia in the same relation as apomorphia to morphia, an atom of water being abstracted in its formation. Apocodeia is more stable than apomorphia; but the action of reagents upon the two bases is very similar. As regards their physiological action, the hydrochlorate of apocodeia is a mild emetic, while that of apomorphia is an emetic of great activity. Other bases have been obtained by Wright by the action of hydrobromic acid on codeia. In two of these bases, bromotetracodeia and chlorotetra-codeia, four molecules of codeia are welded together, so that they contain no less than seventy-two atoms of carbon. They have a bitter taste, but little physiological action. The authors of these valuable researches were indebted to Messrs. Macfarlane for the precious material upon which they operated. We are indebted to Crum Brown and Fraser for an important work on a subject of great practical, as well as theoretical, interest—the relation between chemical constitution and physiological action. It has long been known that the ferrocyanide of potassium does not act as a poison on the animal system; and Bunsen has shown that the kakodylic acid, an arsenical compound, is also inert. Crum Brown and Fraser found that the methyl compounds of strychnia-brucia and thebaia are much less active poisons than the alcoloids themselves; and the character of their physiological action is also different. The hypnotic action of the sulphate of methyl-morphium is less than that of morphia. But a reverse result occurs in the case of atropia, whose methyl and ethyl derivatives are much more poisonous than the salts of atropia itself.

THE POST PLIOCENE GEOLOGY OF CANADA,

By J. W. DAWSON, LL.D., F.R.S., F.G.S.

PART II.-LOCAL DETAILS.

Before entering into the special consideration of this Second Part of the subject, I desire to call attention to some additional facts bearing on two of the most remarkable properties of the Post-pliocene deposits of the Northern Hemisphere, namely their general similarity of arrangement, and their local diversities.

In the first part of this memoir, taking the Post-pliocene of the Lower St. Lawrence as a type, I showed that it has its parallel, with but slight general difference, in the wide-spread superficial deposits of the interior of North America surrounding the great lakes, and that the Post-pliocene deposits of Scotland and Scandinavia almost precisely resemble those of Canada in the general sequence of deposits. Since that part was published, additional illustrations have been afforded by papers in the Geological Magazine by Mr. Hull, and Mr. Mackintosh, by papers and discussions on the Eskers of Ireland, at the meeting of the British Association, and by an able monograph on the Estuary of the Forth, by Mr. David Milne Home. Mr. Hull, who is a "Land Glacialist," arranges the deposits of the Drift Period in the British area in the following three groups, in descending order, in accordance. with Prof. Ramsay's observations in England, and his own in Ireland.

1. Upper Boulder-clay, which he regards as "generally marine." In Canada, this is represented by the loose boulders and partial boulder deposits of the Upper Saxicava Sand.

2. Shelly marine sands and gravels belonging to the greatest depression of the land, and representing our Saxicava Sand and Leda Clay.

3. Lower Boulder-clay, which represents the true or principal Boulder-clay of Canada. This Mr. Hull attributes "chiefly to land ice."

In Ireland, it would thus seem that the principal sub-divisions of the Post-pliocene can be recognized, and Mr. Kinahan has described the remarkable ridges of gravel called eskers which run