On the Methods of Analysing the Superphosphates. By Professor VOELCKER, F.C.S. In this paper Dr. Voelcker reviewed the different methods of analysing superphosphate, and directed attention to the fact that the biphosphate of lime in commercial superphosphates is decomposed when the latter are boiled out at once with water, in consequence of which the amount of soluble phosphate is always obtained too low if boiling water is employed for extraction. He showed likewise that the amount of organic matter and ammoniacal salts in superphosphate cannot be determined as usually done by burning, inasmuch as sulphuric acid is thereby driven out, and the per-centage of organic matter obtained too high. Superphosphates often contain common salt in considerable quantities; in determining the alkaline salts, the common salt is obtained as sulphate of soda, and has to be stated in the results of chloride of sodium. He next pointed out the variable composition of the precipitated phosphates, and recommended in accurate analyses the method of Wöhler for determining the composition of the phosphates. Allusion having been made to the irrational manner of stating the results of analysis, Dr. Voelcker described his own plan of analysing superphosphate, of which the following is a brief abstract. Water and nitrogen are determined as usual. 30 to 35 grains of superphosphate are exhausted three or four times with two ounces of distilled water each time, and then boiled out with sufficient water to obtain an excess of gypsum in solution. The insoluble portion is collected in a weighed filter, dried, weighed, and then burned. The ash is then dissolved in HCl, the solution precipitated with ammonia, and the filtrate from insoluble phosphates with oxalate of ammonia. The portion dissolved in water is concentrated with the addition of some HCl to prevent phosphates falling down, the soluble phosphates are then thrown down with ammonia, the filtrate from phosphates is precipitated with oxalate of ammonia, and the filtrate from lime evaporated for alkaline salts. In accurate analysis the phosphates have to be analysed. On the Proportion of Organic Phosphorus in Legumine. The presence of phosphorus in legumine, contained in it in organic combination and not in the form of phosphates, was shown by the author by deflagrating a mixture of legumine with carbonate of soda and nitre, dissolving the white residue in dilute hydrochloric acid, and precipitating the sulphuric acid with BaCl, removing the excess of BnO by pure sulphuric acid, adding to filtrate from BnO, SO3 ammonia to throw down any phosphates present, evaporating to small bulk, and precipitating finally phosphoric acid with ammoniacal sulphate of magnesia. In this way the following results were obtained: 1. Legumine from green peas. Per-centage of sulphur ,, phosphorus ash. ⚫870 1.383 . 1.100 2. Legumine from green peas thrown down with very little Ā. Per-centage of sulphur •571 ,, phosphorus 3. Legumine from green peas precipitated with excess of Ã. Per-centage of sulphur ⚫851 phosphorus On the Preservation of Albuminized Collodion Plates. By W. SYKES WARD, F.C.S. Having made numerous experiments on the application of albuminized collodion according to Taupenot's process, in comparison with collodion washed and covered with gelatine, according to the process published by Dr. Hill Norris and others, the author found the albuminized collodion process to give better results in all respects, excepting that of deteriorating by keeping. He also found that plates prepared by Taupenot's process were affected by the wood of the dark slide, especially in some instances in which he employed unvarnished cedar wood. In the hope of combining the advantages of both processes, he poured on the plates prepared in accordance with Taupenot's process, and whilst yet wet, various solutions of gelatine and metagelatine, and found that these had the desired effect of enabling him to keep the sensitized plates without deterioration at least four times as long as he could, under similar circumstances, keep the plates not so protected. The additional coating of metagelatine also gives a clearness, brilliancy, and transparency to the negative which is seldom obtained by the ordinary process. The coating of metagelatine is applied after the sensitized plate has been carefully washed, and may be dried by heat, or in the ordinary manner. The following is the formula preferred : Dry metagelatine Lump sugar Glacial acetic acid Water On the Processes for the Detection of Fluorine. By Professor G. WILSON, M.D., F.R.S.E., F.C.S. The author made an oral communication on M. Nicklès' recent observations on the etching of glass as produced by the vapour of fuming sulphuric acid at a high temperature, and disputed the validity of Nicklès' conclusion, that his results prove the inapplicability of glass to the detection of fluorine in the form of hydrofluoric acid. He also drew attention to the impossibility of detecting minute traces of this acid, if quartz, as proposed by Nicklès, was substituted for glass as the material to be etched, and stated his intention of publishing at length his investigations on the relative suitability of glass and quartz for the detection of fluorine. On the Time required by Compounds for Decomposition. By Dr. T. WOODS. The object of this paper was to prove that all compounds require a certain length of time in which, under similar circumstances, they can be decomposed; that this time is invariable in amount, definite and specific. It was first shown experimentally that different compounds require different "times" in which to decompose. This was done by making a galvanic pair, one end of which was zinc in sulphuric acid, the other end, in a porous cell, platina in the compound to be decomposed. When the metals are joined externally, a galvanometer being included in the circuit, the needle shows the amount of electricity in circulation, and consequently the rapidity with which the zinc is being dissolved, and therefore the "time" in which the decomposition of the compound is going on. By successively using different compounds, the time for the decomposition of each was seen, and for the same compound always to be the same under like circumstances. It was also shown that the length of time each compound requires for decomposition was proportional to the amount of heat absorbed by the decomposition; the more heat absorbed the longer it required to absorb it; so that the interesting fact was proved, that all compounds require the same length of time to absorb the same quantity of heat in decomposing. It was shown that the galvanometer in this arrangeinent acted the part of a thermometer of chemical action, as the needle varied exactly with the amount of heat absorbed in a given time. The paper urged the importance of attention being paid to thermo-chemistry, and claimed the precedence of all others on the subject it treated of, as the "time" of action in chemical changes had not before been noticed. It concluded by expressing a doubt if electricity and heat could be the same agent, or modification of it, as equivalents of substances always produce, in combining, the same amount of electricity, but very different amounts of heat. GEOLOGY. Notice of the occurrence of a Boulder of Granite in the White Chalk of the South-east of England. By ROBERT GODWIN-AUSTEN, F.R.S. THE author described first the threefold division of the cretaceous series of the South-east of England; the extent of the area occupied by each division, and the conditions of accumulation thus severally implied-that, commencing from shallow water, each shows more extended boundary lines, and increasing depth. 1. Littoral shingle of Lower greensand or Neocomian group at Farringdon; deepest deposits in Neocomian clays, with Bivalves in normal position, not exceeding ten fathoms. 2. Gault had its deep beds over South-east parts of England, its littoral ones in the West, as in the Halden-sands. 3. The area of the white chalk ranged as far North as the North of Ireland, and from the coast of Scotland to the area of the Baltic, and thence occupied a broad zone over North Germany. In Western Europe the conditions under which the white chalk was accumulated were remarkably uniform; for the whole of the Anglo-French basin (Seine), 800 feet may be taken as its average thickness, the whole a deep-water accumulation. Rolled shingle and fragments of extraneous rocks have been found in the chalk, and are to be seen in several collections; they are all of crystalline, mostly granitic rocks, and their size is not considerable; yet in every case they are beyond the moving power indicated by the white chalk. Modes of transfer of marginal materials into great depths are, 1. By floating sea-weeds. Illustrations of this are to be seen on most coasts, and evidences of it may be detected in most of the older sedimentary deposits. 2. By floating ice. Description of the Croydon Granite Boulder.-Form, size, and weight such that it could only have been moved by ice; other materials associated with it, such as rounded pebbles of other crystalline rocks and siliceous sand. Such an association of materials sinking in one place, shows that they were held together in the act of sinking, as also when they sank into the fine calcareous mud of the chalk sea-bed. The author abstained from entering upon a description of the rocks found associated with the Croydon boulder, but stated that such an assemblage existed only in the Scandinavian and other northern regions. The inferences to be derived from the foregoing considerations have a very interesting bearing on the physical geography of the North European area, at the period of the greatest expansion of the Cretaceous sea. There were regions of the globe then, as now, where coast-ice was periodically formed, was broken up and dispersed; these regions lay to the north of the area of the white chalk of West Europe, and the white chalk ocean extended continuously up to such latitudes. Why, if ice was the transporting agent, such materials are not more common, was explained with reference to the present course taken by the icebergs and ice-floes of the Atlantic. During the Drift period of the Pliocene division of geological history, the set of the liberated ice was more eastward, and was dependent on considerations which are well understood and can be made available for every geological period. On Carboniferous Limestone Fossils from the County of Limerick, collected by the Geological Survey. By W. H. BAILY, F.G.S. The author in this communication gave a brief notice of an extensive collection of fossils recently made by the Geological Survey in the neighbourhood of Askeaton county of Limerick, which, from its containing several new forms, and the fine state of preservation of many of the specimens, presented points of structure and other peculiarities not before described. The fauna of the carboniferous limestone period, which is usually one of the richest in zoophytes, in this collection is represented only by a small proportion, principally belonging to the division Zoantharia tabulata of Prof. Milne-Edwards, amongst which are the genera Michelinea and Chatites, with the characteristic and extensively distributed coral Amplexus coralloides. The Echinodermata, which are most familiar to us in a fossil state, in this collection belong almost entirely to one division of crinoids, the Melocrinidæ, consisting of numerous detached bodies, principally of Platycrinus and Actinocrinus, genera almost exclusively confined to this formation. Remains of animals of the class Bryozoa or Polyzoa, now included with the Mollusca, are well exhibited by various forms, principally belonging to the family Reteporidæ, amongst which are fine specimens of the well-known form Fenestella membranacea of Prof. Phillips. Of the Brachiopoda, the family Terebratulidæ are represented by but one species, the Terebratula hastata, of which there is a numerous and fine series. Of the Spiriferidæ, there are several characteristic species, together with the Athyris Roissyi, a singular and rare form belonging to this family, in which the lines of growth are developed into expansions, giving it a fringed appear ance. Of the family Rhynchonellidæ, are the common forms of Rhynchonella pugnus and pleurodon. The Orthidae are represented by the well-known Orthis resupinata, and the very rare species Orthis radialis, and other well-known forms. Also numerous examples of several characteristic and some rare species of the family Productidæ are found, including Productus aculeatus; and a new species. Of the genus Chonetes there are several interesting and rare varieties, including C. variolata (D'Orb.) and C papilionacea. The Conchifera, or Lamellibranchiata, form a fine series, containing several new forms, amongst them being several species of the genera Aviculopecten and Pteronites (M'Coy), shells having an oblique axis like most of the so-called Pectens of the coal-measures. Of the singular shell called Conocardium Hibernicum (Pleurorhynchus of Prof. Phillips) several instructive specimens were collected, showing the expanded keel and siphonal tube, which in some species is still more extended, being probably analogous (as suggested by Mr. S. P. Woodward in his 'Manual of the Mollusca') to the soft, elongated siphons of a remarkable group of cockles inhabiting the inland salt seas, Aral and Caspian, burrowing in mud; also a second species, of which several specimens were collected, some of them attaining a larger size than the C. Hibernicum, being remarkably perfect, and having a long siphonal tube, which Prof. De Koninck agreed with the author in considering an undescribed form. He proposed, therefore, to dedicate this magnificent species to that distinguished palæontologist under the name of Conocardium Koninckii. There are several species of the genus Cardiomorpha, one of which, C. Koninckii, is new to Britain, and another, a new species, of large dimensions. The Gasteropoda, or univalve shells, are also numerously represented by many genera and species, including a new species of Macrocheilus, and other undescribed forms. Of the Nucleobranchiata, believed to be allied to the floating shells of the present day, this collection contains several species of Bellerophon and Porcellia Puzo, a discoidal form of great rarity. The highest order of Mollusca, and most important geologically, are those of the Cephalopoda, which are here remarkable for size and rarity of form, all belonging to the order Tetrabranchiata. The Nautilidæ contained many large and fine specimens, some of them being new species. Of the Orthoceratidæ, specimens were collected of Orthoceras Muensterianum, fine examples of O. dactyliophorum, and the peculiar forinsof Gomphoceras (Poterioceras) fusiforme and Cyrtoceras Verneuilanum; also of the Goniatites, a division of the Ammonitidæ, several species, including G. crenistria and fasciculatus, alluded to as contained in this collection, some of them showing external markings and others being new forms. On a New Fossil Fern from the Coal-Measures near Glin, County The fossil plant alluded to by the author, and of which an enlarged representation was given, was collected by Mr. G. Henry Kinahan, of the Geological Survey, from the black shale above the coal townland of Ballygiltenan Lower, county of Limerick, associated with ordinary coal plants. It appeared to be the central portion of a frond, with about twenty alternating pinnules, which are apparently covered by thecæ, or cases of the reproductive germs, presenting an appearance somewhat resembling rows of small flowers. The unique character of this singular plant, possessing, as it does, a form so totally unlike any recent or fossil plant, combined with the rare circumstance in fossil ferns of the carboniferous period, that of bearing organs of fructification, which here appear to be so fully developed, renders it of great interest, and may possibly constitute it a new generic form. On the Drift of West Galway and the Eastern parts of Mayo. The author sets out by alluding to the interest and importance of the Irish driftsi general, which are well developed in the district to which his paper refers. They differ from the drifts of many other countries by containing no fossiliferous evidence of their comparative date and, to account for the absence of shells or any traces of boring molluscs in their materials, the author suggests that the remains of those great drifts, which are now exposed, never formed the surface of the former sea-bottom, but were probably situated at a depth to which no shell-fish ever reached. He divides the drift of his district into three principal divisions; namely,― 1. The Clay Drift, from a point between the south-east and the west, forming cliffs on the north, east, and south shores of Galway Bay. 2. The Great Boulder Drift, from a point between the north and the west, overlying the former. 3. The Escar Drift, forming the chains of gravel hills in the interior of the country, from the south-west. The direction and sequence of those drifts are inferred from their mineralogical characters and relative positions. The perfect round forms of the Escar Hills, and the complete curves that their beds or layers generally exhibit in any stratified section, not only prove their subsequency to the other drifts, but show that their emergence from the waves, at which time they must have received their present contour, did not take place during any glacial period; for if icebergs had been moving about, and grooving the rock bottom of the shallowing sea, the Escars would scarcely have escaped their action, which would be recognized in the tabulation of their summits, or other significant appearances. The long ranges of those gravel hills may show the resultants of currents that had been subdivided from the main stream, and met again at large angles beyond the limits of opposing hills. He refers to a fact which he considers worthy of note, from being at variance, as he believes it to be, with recognized theory. He often observed that in the Escar drift, the coarser gravel and boulders betray a tendency to arrange themselves in the upper parts of the mass; and he has remarked the same phenomenon in the shoal beds periodically formed by river floods. He maintains that it is to the power of moving water, and not either to land glaciers or floating ice, that the great boulder drift of his district is also to be attributed. The fact of large boulders being found on the sides and summits of hills, which they must have ascended, sufficiently refutes the land-ice hypothesis; and the floating-ice theory is rendered improbable by the appearance of a regular increase in number, as well as in size and angularity, of the erratic blocks as they are followed towards their source. Their decrease in number, according to their remoteness from their parent rocks, might, indeed, be accounted for on glacial principles, but not so easily their decrease in size; for though the ice-raft may waste away by degrees, and its powers of buoyancy become less, still this must be thought to affect the total quantity, rather than the individual parts of the load that it bears. As its cliffs succumb in its progress through the warm sea-waves, its burden may gradually be reduced; but there is no reason why the largest masses should not be found among the mixed materials which are still carried on its contracting area. If ice, therefore, were the transporting cause of this drift, we should expect to see, scattered over the land, even a few large boulders derived from distant localities; but those are never found so situated; they must be looked for near their source. The clay drift is in some places stratified, and in others amorphous; and it presents no phenomena which, in the author's opinion, oblige us to have recourse to the agency of ice to account for its formation, while its southerly |