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If to any extent the movement of the bowlders was by rotation* in the ice mass, the larger and more equidimensional sandstones would have the advantage in the race. The angu. larity of many of the sandstone blocks, however, renders rotation for this case doubtful.

To sam up briefly the facts of distribution: We find the Archæan and more northern Paleozoic fragments strewn over the whole district at all altitudes, but diminishing southward in size, and sparse in ainount on the highest hills, especially to the southward, where the tops of the ranges are often surprisingly free from transported material.t The Oriskany sandstone drops off from the hilltops after about 25 miles and disappears, so far as observation goes, at 40 miles. The Lower Helderberg and Corniferous limestones appear only for six or eight miles at high levels, but continue far down in the valley drift. As a rule local material far exceeds the imported, at a given point. Exceptions to this rule are due to special local conditions. We may note as factors on which the local distribution and south ward extension depend : accessibility of the preglacial ledges for plucking; the bedding and joint planes and power of current, as controlling size and number of fragments plucked ; surrounding topography as related to removal; southward extension and limit of the current doing the pluck. ing; lithological character as controlling change of form and reduction of size during carriage ; zone of carriage and mode of transport as affecting form, size and manner of deposition. This is doubtless a partial statement, and the several factors will be found in conibinations of endless variety.

Whatever may be said of the more northern material, it seems plain that that from the Oriskany Falls region was carried in the basal portions of the ice. The position of the ledges and the combing out of the greater number of large blocks by the hill range, seem to assure this view. A valley tongue, whose top barely reached and caught away the blocks, does not satisfy the case. It could not have grappled the masses with sufficient power. It certainly could not have wrought the very considerable elevation which their present situation demon. strates. Had the bowlders risen to the upper zones of the ice wbile it was at its greatest thickness, the hilltops should show more of far travelled material. It is to be added that while some of the bowlders are rounded, others in the same groups are notably angular, joint blocks carried from 5 to 12 miles with almost no reduction of angles.

* T.C. Chamberlin, Rock Scorings of the Great Ice Invasions, 7th Ann. Rep. U.S. G. S., pp. 232-233.

+ See ref. to Rep. Z., Pa. Surv. already cited; also, J. C. Branner, this Journal, III, vol. xxxii, p. 365..

Cf. R. D. Salisbury, Aon. Rep. Geol. Surv. X.J., 1891, pp. 68-70.

The inquiry has afforded general suggestions as to the amount of glacial reduction of the surface of the district. The northern section seems to have suffered most. At and south of the moraine which runs so nearly coincident with the divide, the hills are often drumlin-like, or at least show much futing, displaying the “ linear” topography to perfection. On the slope which descends to the Mohawk, the ice acted with power. În the southern section, the country was less effectively scored and was planed during a shorter period. The bowlder drift in the best strewn fields is more impressive in its appearance, than its actual cubic contents would justify. The Lower Helderberg shelf at Oriskany Falls, so conspicuously stripped of the superjacent sandstones, would probably much more than receive all the Oriskany bowlders dispersed to the southward, if brought back and corded to the thickness of the ledge from which they were borne. If we say that four times as much sandstone has been crushed and carried down the valleys and to the sea, the amount would still be relatively insignificant. Erosion in certain situations, redistribution within moderate distances, and topographic changes, have been very great. Actual reduction of the general surface toward base level doubtless proceeded rapidly during glacial time, but even then, the process was rapid only in the geological sense, and the result a minute fraction of what has been accomplished since the region became a land surface.

Colgate University, December, 1994.

SCIENTIFIC INTELLIGENCE.

1. CHEMISTRY AND Physics. 1. On the Determination of high Fusing Points. - A new method of determining high fusing points has been devised by VICTOR MEYER in conjunction with RIDDLE and LAMB, based on the principle of measuring the temperature by means of a small air thermometer made of platinum. At the instant when the substance under examination fuses, the air in this thermometer is expelled by means of a soluble gas, into a graduated tube containing a liquid in which the expelling gas is dissolved. The substance to be examined is placed in a small platinum tube, which is attached to the bulb of the air thermometer, and the whole is immersed in a fused salt having a melting point considerably below that of the substance. The air thermometer consists of a spherical bulb of platinum, about 25°c in its capacity, having two somewhat long capillary tubes of the same metal attached to it, one of which just enters the bulb while the other reaches to the bottom. At top these tubes are bent at right angles, in opposite directions. In making a determination, the salt constituting the bath, contained in a large platinum crucible, is fused and the bulb of the air thermometer, with the attached substance-tube, is immersed therein; connection being made between one of the capillary tubes and a carbon dioxide apparatus and between the other and the gas measuring burette. To fix the point of fusion, a fine platinum wire is previously immersed in the fused substance, this wire being attached to a weight by means of a cord passing over a pulley. When now the substance is again fused by means of the bath, the wire is released and the weight falls and strikes a bell. The current of carbon dioxide is then started and by its means the air in the air-thermometer is driven into the measuring burette. Knowing the capacity of the thermometer, and the volume of air expelled, the temperature can be calculated. By the new method the author has determined the fusing points of KCl as 800:0°, of KBr as 722:0°, of KI as 684.7°; and of NaCl as 815.4°, of NaBr as 75707° and of Nal as 661.4°; showing that a rise in the atomic mass of the halogen causes a fall in the melting point. Moreover, he observed for RbI the value 641.5° and for CsI, 621:0°; that for KI being 684•7o. For CaC), the susing point obtained was 806:4°, for SrCl, 832:0° and for BaCl,, 921.8°. While therefore the melting point falls as the atomic mass rises, in the case of the alkali iodides, the reverse is the case with the chlorides of the alkali-earths. In either case however, the salt of intermediate molecular mass shows an intermediate susing point. Ber. Berl. Chem. Ges., xxvii, 3129, November, 1894.

G. F, B. 2. On the Preparation of anhydrous Hydrogen peroxide.-It bas been shown by WOLFFENSTEIN that bydrogen peroxide, hitherto considered as very unstable, is capable of concentration and even of actual distillation under diminished pressure, with but little loss from decomposition. Ascertaining that the loss on concentration either in the air or ip vacuo arose from vaporization, the author was led to attempt its distillation. A quantity of the commercial peroxide concentrated until it contained 50 per cent of H, 0,, was purified by extraction with ether; whereby the quantity of H,O, was raised to 73 per cent. On submitting this to distillation on the water bath at the pressure of 68mm of mercury, two fractions were obtained, the one boiling at 71°-81° and the other at 81°-85°; the former containing 44 per cent H,O, and the latter 90.5 per cent. On fractioning again the latter product, a distillate was obtained at 84°-85° which contained over 99 per cent of H,O, and was practically pure peroxide. It is a colorless syrupy liquid, which scarcely wets the containing vessel and which evaporates in the air. It produces a prickly sensation upon the skin, causing a white spot. Even after distil. lation with soda it reacts strongly acid. Further experiments have shown that the treatment with ether is not essential; a 3 per cent solution being readily concentrated by repeated fractioning to give the pure substance boiling at 84°-85°: - Ber. Berl. Chem. Ges., xxvii, 3307, December, 1894.

G. F. B. 3. A supposed Nero Element in the Nitrogen group.-A preliminary note has been published by Bayer upon a supposed new element which he has discovered in the residues from the older process for the preparation of alumina from the red bauxite of Var. After removing the vanadium as ammonium vanadate and the chromium as hydrate, the filtered liquid is saturated with hydrogen sulphide, again filtered and the sulphides precipitated by hydrogen chloride. This precipitate is deep brown in color, dries to an earthy mass and burns readily to a bright brown powder, evolving sulphur dioxide. It ignites on treatment with strong nitric acid, forming a dark brown solution, which deposits a small quantity of a yellow precipitate containing molybdic and arsenic acids. This brown liquid is free from tin, antimony and tellurium, but contains traces of vanadium, molybdenum and selenium. These are removed by calcining the recently precipitated sulphides, treating the residue with ammonia and ammonium nitrate and concentration of the solution. Two sets of crystals are obtained, one being ammonium molybdate, the other a less soluble substance in cubic crystals olive.brown in color. By dissolving these latter crystals in hydrogen chloride and treating the solution with hydrogen sulphide a trace of molybdenum is removed. Upon allowing the filtered liquid to evaporate in the air, it becomes at first bluish-violet and contains the new element in a lower state of oxidation ; subsequently changing to lemon-yellow. In this condition, the oxide is markedly acid, corresponding probably to R,0 The acid is soluble in water, and on evaporation is deposited in yellow crystals fusing at a red heat to à brownish mass. Ammonia converts it into a crystalline olive-green powder, which dissolves in water and crystallizes out in cubes on cooling. After reduction with hydrogen sulphide in presence of hydrogen chloride, the acid yields a voluminous dark violet-brown precipitate, rapidly becoming crystalline. When treated with ammonium sulphide the yellow solution of the acid becomes dark cherryred from the formation of a sulphosalt. From this solution acids precipitate a sulphide of the color of iron rust. Silver nitrate gives a green precipitate soluble in nitric acid and in ammonia. Magnesia mixture gives a green precipitate in relatively large crystals. A nitric solution of ammonium molybdate gives a yellow precipitate as in the case of phosphoric acid. The chlorides of the new element appear to be volatile, and are readily soluble in water.-Bull. Soc. Chim., III, xi-xii, 1155, December, 1894.

G. F. B. 4. A Short History of Chemistry.-By F. P. Venable, Ph.D., 12mo, pp. viii, 163. Boston, 1894 (D. C. Feath & Co.). This little book is based upon a course of lectures which the author has delivered for several years to his classes in the University of North Carolina, in the belief, as he tells us that, “one of the best aids to an intelligent comprehension of the science of chemistry

is the stridy of the long struggle, the failures and the triumphs of the men who have made this science for us." The first part describes the genesis of chemistry, the second treats of the alchemists, the third considers qualitative ehemistry, the fourth has 10 do with quantitative chemistry, the fifth discusses structural chemistry, and the sixth is devoted to special branches of chemistry. Within 80 small a compass, it is evident that but a limited treatment of so broad a subject can be given. The book appears to be well written and seems adapted to be of service in those institutions where the history of chemistry forms a part of the prescribed course.

G, F. B. 5. Multiple Resonance.—Various investigations have been made in the subject of the interference of electrical waves; and apparently the diffraction of these waves has been satisfactorily shown. V. BJÉRKNES points out, however, that an important difference exists between the phenomena of the interference of light waves and those of electrical waves. In the case of light we observe the phenomena by means of instruments which may be termed indifferent, that is, instruments which do not influence or are not influenced by the source emitting the waves. Whereas in electrical resonance, the resonator is especially sensitive to the various conditions of the electrical oscillation. In general the oscillator is more quickly damped than the resonator. Damped waves do not in general show sharp nodes. Various conditions may arise, which depend upon the circumstances of damping. If the resonator in comparison with the oscillator is strongly damped, the ventral segments and nodal points are relatively well defined. While the resonator is relatively insensitive to a stimulus of its own peculiar rate of oscillation. On the other hand, if the oscillator is strongly damped and the resonator relatively weakly damped, as is the condition in most of Hertz's apparatus, the ventral segments and nodes are not clearly defined, while the resonator is especially sensitive to the excitement of its own peculiar oscillations. In the experiments with a diffraction grating these peculiarities must be considered. What may seem to be spectral dispersion may be only the multiple resona:!ce of the instrument.-Ann. der Physik und Chemie, No. I, 1895, pp. 58–63.

J. T. 6. Spectrum analyses of the color of the water in the Blue Grotto, of the Swiss ice holes and of the Yellowstone Springs.H. W. VOGEL, twenty years ago, examined with a spectroscope the light in the blue grotto at Capri. The water inside and outside the grotto showed an absorption band between the Frauenhofer lines b and E together with a disappearance of the red end of the spectrum up to the line D. During the present year he has had an opportunity to examine the water and the light of the walls of the other grottos (green and red) of the island. He found no trace of the absorption band which he had noticed in the blue grotto in his examination of the walls and water in these colored grottos. The red end of the spectrum, however, was

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