bluuebunny/crossref_metadata_2025 huggingface dataset:
VIII.—On the Rotation of a Rigid Body about a Fixed Point
Authors: Tait
Published: January 2013

Although it is very improbable that there remains to be discovered any new, and at the same time simple, fact connected with a question which has been elaborately treated by many of the greatest mathematicians of this and the preceding century, the employment of a new mathematical method may enable us to present some of their results in a more intelligible form, and with far less expenditure of analytical power than has hitherto been deemed necessary; and it may give us such an insight into the question, that we shall be able easily to discover the mutual relations among the various processes which have been already employed; so far, at least, as these differ in principle, and not merely in the peculiar co-ordinates assumed for the purpose of simplifying the equations. Such a method is that of Quaternions, which seems to be expressly fitted for the symmetrical evolution of truths which are usually obtained by the ordinary Cartesian methods only after great labour of calculation, and by modes of attack so indirect, and at first sight so purposeless, as to bewilder all but a very small class of readers. Quaternions afford so clear a view of the nature of the question they are applied to, that even the student, if he have some little knowledge of them, can often see why a transformation is made, whose object he would have been unable to discover had the problem been masked in the unnecessarily artificial difficulties of Cartesian geometry, or the outrageously repulsive formulæ of spherical trigonometry.
XI.—On the Practical Application of Reciprocal Figures to the Calculation of Strains on Framework
Authors: Jenkin Fleeming
Published: January 2013

The theory of reciprocal figures used as diagrams of forces was first completely stated by Professor T. Clerk Maxwell, in a paper published in the “Philosophical Magazine,” April 1864. The following definition of reciprocal plane figures, and their application to statics, are there given as follows:—

“Two plane figures are reciprocal when they consist of an equal number of lines, so that corresponding lines in the two figures are parallel, and corresponding lines which converge to a point in one figure form a closed polygon in the other.”

“If forces represented in magnitude by two lines of a figure be made to act between the extremities of the corresponding lines of the reciprocal figure, then the points of the reciprocal figure will all be in equilibrium under the action of these forces.”

The demonstration of this statement is given. The conditions under which stresses are determinate, and some examples of reciprocal figures, are also given in the paper, which leaves nothing to be desired by the mathematician.
XIV—Observations on New Lichenicolous Micro-Fungi
Authors: Lindsay W. Lauder
Published: January 2013

In the course of my studies on the Microscopic Anatomy of Lichens, during the last fifteen years, I have frequently met with various more or less minute Parasites—mostly black and punctiform or papillæform—sometimes disciform or maculæform—affecting either the thallus or apothecia of lichens, or both thallus and apothecia. They grow equally on foliaceous and crustaceous lichens, especially of the following genera:—Parmelia; Physcia; Umbilicaria; Solorina; Peltidea; Nephromium; Sticta; Stereocaulon; Usnea; Neuropogon; Cladonia; Bæomyces; Squamaria; Placodium; Lecanora; Pertusaria; Thelotrema; Lecidea; Graphis; Endocarpon; Verrucaria.
XVI.—On the Alkaloids contained in the Wood of the Bebeeru or Greenheart Tree (Nectandra Rodiœi, Schomb.)
Authors: Maclagan Douglas , Gamgee Arthur
Published: January 2013

In a paper read before the Royal Society of Edinburgh in April 1843, Dr Maclagan described the general properties of the alkaloid, whose presence had been indicated in the bark of the bebeeru or greenheart tree, by Dr Rodie of Demerara, and described the mode of preparation of its sulphate for medicinal use. The fact that bebeerine appeared to possess marked antiperiodic properties, rendered its careful chemical study desirable, and accordingly the alkaloid, purified as far as possible, was subjected to analysis by Drs Maclagan and Tilley. It resulted from this research that bebeerine is an uncrystallisable base, very soluble in alcohol, less so in ether, and very sparingly so in water. It forms with acids salts which are all uncrystallisable. With perchloride of gold, mercury, copper, and platinum, it gives precipitates which are soluble to a certain extent in water and alcohol, but which are deposited in a non-crystalline form when the solution cools. To this base the author assigned the formula C35H20N2O6(C = 6). Von Planta subsequently attempts to purify further the alkaloid, and assigned to it the formula C36H21O6N(C = 6) or C18H21O3N(C = 12.)
XXV.—On the Hydrodynamical Theory of Seiches
Authors: Chrystal
Published: January 2013

§ 1. The variations of the surface-level of lakes due to the direct action of wind and rain, and the smaller disturbances caused by surface waves, of small or moderate length, due to the action of the wind and the movement of boats and animals, must have been familiar phenomena at all times. The first accurately recorded observation, that lake-levels are subject to a rhythmic variation, similar in some respects to the ocean tides, seems to have been made at Geneva in 1730 by Fatio de Duillier, a well-known Swiss engineer. Owing to the peculiar configuration of the Geneva end of Lake Léman, these variations occasionally reach a magnitude of 5 or even 6 feet; and Duillier mentions that they were known in his time by the local name of “Seiches,” which has now been applied to rhythmic alterations of the level of lakes in general.
XII.—Studies on the Pharmacological Action of Tetra-Alkyl-Ammonium Compounds: II. The Action of Tetra-Ethyl-Ammonium Chloride
Authors: Marshall C. R.
Published: January 2013

The pharmacological action of tetra-ethyl-ammonium chloride has been investigated to a limited extent by Tillie, Santesson and Koraen, Tappeiner, Boehm, and Höber and Waldenberg, in the course of other researches. Tillie, and Santesson and Koraen, describe its action on frogs; Tappeiner merely states that it has no paralysing effect on the respiration of the rabbit; Boehm, and Höber and Waldenberg, refer only to its effect on the isolated frog's muscle. The descriptions of the action of the iodide, which has been investigated by Jordan, Brunton and Cash, Rothberger, Jacobj and Hagenberg, and Barger and Dale, in the course of other work, are also somewhat meagre. Brunton and Cash, and Jacobj and Hagenberg, describe its action on frogs, and Brunton and Cash its action on rabbits; but Jordan merely says that it produces on frogs a curare-like action but no muscarin effect, and Barger and Dale only state that it has no sympathomimetic action. The investigation of Rothberger was limited to its antagonistic action towards curarin.
XVI.—On the Fossil Osmundaceæ
Authors: Kidston R. , Gwynne-Vaughan D. T.
Published: January 2013

The present part of this memoir contains descriptions of four additional specimens of Osmundites which have been obtained from various sources.

We are indebted to Dr G. Nathorst for the material of Osmundites spetsbergensis, Nathorst MS., which was first collected by Dr G. Nordenskiöld on the Spitzbergen Expedition of 1890 at Nordenskiöldsberg, and subsequently by Dr B. Högbom in 1910 at Van-Mijensberg, Spitzbergen.

Our thanks are also due to Dr A. Rothpletz, Director of the Geologisch-palaeontologische Staatssammlung, München, for kindly placing in our hands the type specimen of Osmundites Carnieri, Schuster, for investigation and redescription.
I.—Observations upon the Structure of a Genus of Oligochœta belonging to the Limicoline Section
Authors: Beddard Frank E.
Published: January 2013

Some time since I published in the Transactions of this Society a paper upon Phreoryctes; the present paper is the second of what I hope will be a series of memoirs upon the structure of the Oligochæta Limicolæ; this will be a parallel series to that upon the Oligochæta Terricolæ, which is being published by me in the Quarterly Journal of Microscopical Science. As I took pains in my paper upon Phreoryctes to point out, in accordance with views previously expressed by myself and by others, that it is impossible to draw a hard and fast line between those two groups of Claparède, it may seem rather illogical to retain this classification—if only in the title of a paper; I do so simply as a matter of convenience, and without in the least desiring to revive these old divisions of the Oligochæta; indeed the genus Moniligaster, which is treated of in the present communication, is by most naturalists regarded as an earthworm; in many points it does undoubtedly agree with certain terricolous genera; but as its affinities, into the discussion of which I shall enter later, seem to me to be more with the Lumbriculidæ, I put it into the Limicoline series; it is useful to have a name corresponding to “earthworm” for those Oligochæta which are not earthworms, and are for the most part aquatic, and I therefore use that term.
II.—On the Transformation of Laplace's Coefficients
Authors: Plarr Gustave
Published: January 2013

The development of the inverse square root

into a series

gives rise to the coefficients Zn, which have been called “Laplace's Coefficients” If in Zn we substitute for z the expression

where

then the function of ψ, which Zn will represent, can most appropriately be expressed by

The object of this paper is to show, by actual calculation, that the coefficients Ns, (functions of x, x′, y, y′) can be worked out by elementary algebraical processes, the only auxiliary taken from higher analysis being the expression of the powers of cos ψ in function of the cosines of the multiples of ψ.

As to our notations, we shall observe throughout the following restrictions:—

1. The function Π(x) shall not be employed otherwise than for integer positive values of x, so that

2. The factorial

will be made use of for integer values only of r (as, for example, r = + 1, or r = − 1, or r = + 2, &c., the exponent t being integer positive.
IV.—Adamantios Koraes, and his Reformation of the Greek Language
Authors: Blackie
Published: January 2013

The appearance of a learned and exhaustive work on the life and labours of Koraes, by a native Greek of great ability, naturally invites the scholars of Western Europe to a grateful acknowledgment of the obligation of the Greek language to this most distinguished of its modern exponents. The fact, indeed, that Greek in this country is popularly talked of as a dead language, and as such taught from books through the eye and the understanding, rather than by living converse with those who speak it, may serve as an apology for the general ignorance that prevails, even in professional circles, with regard to the scholarly achievements of this remarkable man; but the appearance of works of such mark in the living literature of Greece as those of Thereianos, Paspates, Bikellas, Polylas, and others, warns us that it is high time to take note of living Greece as living Greece again, and give to the learned Grecians of the present day their proper share in that homage which we pay so liberally to the great masters of Greek wisdom in the past.

Adamantios Koraes was born at Smyrna in 1748, the son of a Chiote merchant who had removed from the island to the great centre of commerce on the Continent. As a boy young Koraes was remarkable for his love of learning and his hatred of the Turks as the enslavers and debasers of his people; and having inherited a valuable library from one of his maternal relatives, he found it necessary to acquire the Latin language, in which all the famous commentaries on the great Greek classics had been composed.
VI.—The Solar Spectrum at Medium and Low Altitudes. Observations of the Region between Wave-Lengths 6024 and 4861 Å.U., made at Lord Crawford's Observatory, Dun Echt, during the Years 1887 to 1889
Authors: Becker Ludwig
Published: January 2013

At the end of 1886 a method occurred to me of rapidly recording the positions of the lines of the solar spectrum, which I thought might be used with advantage for determining the faint “Telluric dry-gas lines” near D, mentioned in Professor Piazzi Smyth's maps of The Visual Solar Spectrum in 1884. The fundamental idea of the recording apparatus is that of magnifying by some mechanical means the motion of the grating, or prism, to such an extent that it can be recorded on a continuous fillet of paper. The viewing telescope being then firmly clamped, the exact positions of the grating can be pricked off on the strip of paper as the lines are successively brought to the fixed cross in the field of view.

For the satisfactory use of the method two conditions suggest themselves as desirable. First, the punctures should not be less than a good-sized pin hole, and the interval between the closest lines, which the spectroscope is able to separate, should be represented on the paper strip by a space of several tenths of an inch.
XII.—Professor Kelland's Problem on Superposition
Authors: Brodie Robert
Published: January 2013

From a given square one quarter is cut off; to divide the remaining gnomon into four such parts that they shall be capable of forming a square.

[See Trans. Roy. Soc. Edin., xxi. 271.]

Preliminary problem, viz.: To cut a rectangle into three parts capable of forming a square (Figs. 1, 2).

Lay off AX and CY = side of square, join BX, draw YZ ∥ AB, and 1, 2 and 3 will be the required pieces, as is evident.

The problem will be impossible when the length of the rectangle is greater than four times its breadth; four or more pieces may then be required. The problem can be solved in four different ways by drawing the sloping line BX from each of the four angles.

The above is a particular case of the more general problem, viz., to cut a rectangle or a parallelogram into three pieces so as to form another with a given side, as AB (Figs. 3, 4).

In the gnomon (Figs. 5,6), suppose the square EC placed below in the position BK, then the rectangle AK is formed, and can be divided into three pieces by FX and YZ, so as to form a square as before.
XVI.—Strophanthus hispidus: its Natural History, Chemistry, and Pharmacology
Authors: Fraser Thomas R.
Published: January 2013

In former papers on the pharmacological action of Strophanthus, dating from 1869, I selected for description, from the considerable number of experiments that had been made, merely those experiments which sufficed to illustrate the general features of the action, and especially such effects as seemed likely to form a basis for the application of Strophanthus to the treatment of disease.

I had intended to have followed, at no distant date, these preliminary and somewhat fragmentary notices by a more complete description of the pharmacological action, for which, indeed, nearly all the required experimental data had several years ago been obtained; but unavoidable circumstances prevented this intention from being fulfilled. In this part of the present paper the fuller description will be given; and if any excuse were required for doing so, it may perhaps be found in the circumstance that the anticipation of the therapeutic value of Strophanthus has been amply confirmed by the important position now occupied by it as a therapeutic agent.
XVII.—On the Composition of Oceanic and Littoral Manganese Nodules
Authors: Buchanan J. Y.
Published: January 2013

The following analyses were made some years ago, principally with the object of ascertaining the state of oxidation of the manganese in the nodules. The nodules examined came from three different localities, two of them oceanic and the third littoral. Samples marked I., II., and III. are from nodules brought up in the trawl on board the “Challenger,” on 13th March 1874, in lat. 42° 42′ S., long. 134° 10′ E. The depth of the water was 2600 fathoms, and the temperature of the bottom water 0·2° C. The density of the bottom water was 1·02570 at 15·56° C. Being from a high southern latitude, and therefore near the source of surface aeration, the water is highly charged with atmospheric gases, especially oxygen. It contained, per litre, 18·4 c.c. of mixed nitrogen and oxygen, of which 31·81 per cent, was oxygen, and 27·33 c.c, or 53·7 milligrammes, loosely-bound carbonic acid. The position of the station is about 400 miles south-west of the nearest part of the Australian coast, and about 500 miles west of Tasmania. It was the deepest water observed in the Antarctic voyage between the Cape of Good Hope and Melbourne. The haul was a very abundant one, and a few notes which I made at the time may be interesting:—“The water was found unexpectedly deep, the bottom being red clay, with some Foraminifera.
Section I.—Introduction.
Authors: Buchanan J. Y.
Published: January 2013

The Principles of Archimedes*—It is well known that the mechanics of floating bodies, and the laws which govern their equilibrium, were established and enunciated by Archimedes, the Sicilian, in the third century before our era. The following propositions, demonstrated in the first book of his treatise on this subject, embody the fundamental principles of the hydrometer :—

(a) The surface of any fluid at rest is the surface of a sphere whose centre is the same as that of the earth.

(b) Of solids, those which, size for size, are of equal weight with a fluid will, if let down into the fluid, be immersed so that they do not project above the surface, but do not sink lower.
Section III.—Determination of the Specific Gravity of a Saline Solution
Authors: Buchanan J. Y.
Published: January 2013

When determining the specific gravity of a saline solution by the hydrometric method, it is necessary first to find the weight which must be added to the hydrometer to immerse it to the 50-mm. mark when floating in the saline solution at the chosen standard temperature. This added weight is found by a series of observations in exactly the same manner as with the hydrometer in distilled water (see § 14 et seq.).

The details of three series of observations with hydrometer No. 17 in a solution of ⅛ gram-molecule of cæsium chloride in 1000 grams of water at 19·50° are given as an example in Table C. This table is arranged in the same manner as Table A1.
Section IV.—The Control of the Temperature of the Laboratory
Authors: Buchanan J. Y.
Published: January 2013

A laboratory is an inhabited room, and in Northern Europe the temperature of such apartments lies generally between 12° and 20°C. Consequently we find that a large amount of specific gravity work has been done at 15°C. by Gerlach, at 19·5° C. by Kremers, and at 17·5° C. by others ; while the calorimetric work by Julius Thomsen, extending over the last half-century, was all done at the temperature 18° C.
Section V.—Tables
Authors: Buchanan J. Y.
Published: January 2013

General Tables, giving the Facts of Observation ; namely, W, the weight, in grams, of the solution which contains m gram-molecules of the salt dissolved in 1000 grams of water; S, the specific gravity of this solution at the temperature, T, referred to that of distilled water at the same temperature as unity. From these data, Δ, the displacement of the solution, is obtained by the equation Δ = W/S, and it is expressed in grams of water having the temperature T. The symbol adopted for this unit is GT. The numbers printed in italics refer to specific gravities observed at the temperature printed in italics.
Section VI.—General Description of Tables
Authors: Buchanan J. Y.
Published: January 2013

In the tables giving the results of the experiments made with solutions of a particular salt, the weights given are those which would have been used if the weighings had actually been made in a vacuum ; and the standard temperature, T, at which all the operations have been made, is given at the top with the name of the salt, both being constants.

Of the variables, we have under m the quantity of the salt, expressed as the number, whole or fractional, of gram-molecules, which is dissolved in 1000 grams of water, under W the weight in grams of the solution so produced, and under S the specific gravity of the solution referred to that of distilled water as unity, both having the standard temperature T.
Section VIII.—Comments on the Changes in the Values of dΔ — v for Different Values of m in the Case of Solutions of Individual Salts of the Type MR And MRO3
Authors: Buchanan J. Y.
Published: January 2013

The earlier introductory notes and discussion of the values of the specific gravity and displacement explain the precise meaning of these terms. A comparison of the values of the increment of displacement (v) caused by the dissolution of m grammolecules of a salt in 1000 grams of water with the difference (dΔ) of these consecutive increments of displacement possesses considerable interest.
Section IX.—Notes on the Values of v for the Enneads MR and MRO3
Authors: Buchanan J. Y.
Published: January 2013

The increment of displacement produced in 1000 grams of water at 19·5° C, when 1/2 gram-molecule of potassium chloride is dissolved in it, is 14·001 GT; when a molecularly equivalent amount of potassium bromide is dissolved in the same quantity of water, the increase in the displacement is 17·547GT; when the salt in solution is potassium iodide, the number is 22·778 GT. Replacing, therefore, the chlorine by bromine increases the displacement by 3·546 GT; and if the bromine be now replaced by iodine, there is a further increase of 5·231 GT in the displacement; or, replacing the chlorine by iodine causes an increment of displacement of 8·777 GT.
Section XII.—Numerical Details illustrating the Use of the Open Hydrometer
Authors: Buchanan J. Y.
Published: January 2013

For this purpose we will consider in detail the items of the experimental determination of the weight of liquid displaced by the instrument which is designated “Hydrometer A”; it has for some time been in constant use.

A scheme for recording the items of observation is given in § 86.

In the first vertical column the line corresponding to each item is designated by a letter—a, b, etc. In the second column are the symbols used for the principal items, and in the body of the scheme the items are described or explained.
Section XVI.—The Determination of the Specific Gravity of the Crystals of a Soluble Salt by Displacement in its own Mother-Liquor, and the Volumetric Relations between the Crystals and the Mother-Liquor which are Established by the Experiment.
Authors: Buchanan J. Y.
Published: January 2013

The work on the specific gravity of dilute solutions at 19·5° C. reported in the early part of this memoir was interrupted by the arrival of the great anticyclone or heatwave of the summer of 1904, during which observations at a temperature of 19·5° were quite impossible. Indeed, the temperature of the laboratory, whether by night or day, hardly ever fell below 23° C. or rose above 25° C. It persisted over Northern Europe for nearly six weeks, and produced tropical conditions, which were evidenced alike by the high temperature of the air and by its insignificant diurnal variation.
I. On the Parallel Roads of Lochaber
Authors: Dick Thomas Lauder
Published: January 2013

I Had last winter the honour of laying before the Royal Society a few hasty remarks on what are called the Parallel Roads of Glen Roy, suggested to me by an accidental ramble through that valley, in the course of a pedestrian tour in the West Highlands, during the previous August. My curiosity having been much excited by what I then saw, I was induced to revisit the highly interesting district of Lochaber, in the beginning of last June, and had thus an opportunity of devoting three whole days to a more complete inspection of these remarkable shelves, which I was surprised to find, were to be traced through a much more extensive stretch of country than former observation had led me to imagine. My first visit to Glen Roy was accidental; but upon this late occasion, I went with the purpose of endeavouring to put myself in possession of all the facts I could possibly collect, regarding these curious appearances; and in doing this, I had several advantages which I did not formerly enjoy.
V. Memoir on the Repeating Reflecting Circle
Authors: Brisbane Thomas
Published: January 2013

Having had frequent opportunities, during my residence in France, of seeing a great many Repeating Reflecting Circles, several of which I have observed with, and having found much consistency in the results deduced from observations made with them, it occurred to me, that if I could engage Mr Troughton to execute one for me, it would be a most perfect instrument. This he accordingly did; and I trust that the observations made with it, which I am about to communicate, will perfectly justify the opinion I had formed of its precision. The instrument is only of about six inches radius, divided in gold to 20″. I have always been in the habit of choosing for latitudes 30 repetitions, when the weather would permit, divided into three series of 10 each, and reading the angle or arc run through during the series, which completely destroys every imperfection of the division, or reading. In order to determine the time, I have always found six repetitions quite sufficient to give it as correct as equal altitudes.
VII. Account of a non-descript Worm (the Ascaris pellucidus) found in the Eyes of Horses in India. In Letters from Alexander Kennedy, M. D. F. R. S. Edin. to Professor Russel and Dr Hope. With a Description of the Animal
Authors: Brown Thomas
Published: January 2013

When I lately mentioned to you in conversation, the disease in the eyes of horses in India, occasioned by the presence of a worm within the ball of the eye, I thought that you might probably have heard of it before; but as you had not, and are desirous of further information upon the subject, I now take this method of mentioning the circumstances to you, so far as I know them.

The animal occasioning this disease, is termed by the natives about Madras, the “Worm” in the Horse's Eye, by using the corresponding words in their respective languages. I have been told that in Bengal it is called the “Sānp” or the Snake in the Horse's Eye. As it seems more to resemble a fish or an aquatic insect, it might perhaps with more propriety be regarded as an eel.
X. An Examination of some Questions connected with Games of Chance
Authors: Babbage Charles
Published: January 2013

The questions which I propose to examine in the following paper, although not themselves dependent on chance, have arisen entirely from games in which it predominates. To determine some method of betting upon a number of successive events, (and the probability of each of which is either equal to, or less than one-half,) by which a profit shall be realised after a considerable number of them have been decided, is a problem which has occupied the attention, and exhausted the efforts, of one set of speculators, as completely as that of the quadrature of the circle has defeated the labours of another. The first and most simple plan, is that of doubling the stake whenever a loss occurs. This is well known, and has been so frequently practised, as to have acquired a peculiar name; it is technically called the martingal; it requires for its success, that the person who employs it have the power of leaving off whenever he please, and that he have the command of an unlimited capital. If the chance of the events happening is one-third instead of one-half, the stake must be tripled.
XI. On the Radiation of Caloric
Authors: Holland Thomas Crompton
Published: January 2013

The various facts concerning the radiation of caloric present a very interesting subject of inquiry, and various theories have been formed, with a view to their explanation. The principal difficulty has been to explain the facts of the apparent radiation of cold. The most simple theory with respect to these, is that proposed by M. Prevost of Geneva. He supposes, that all bodies are always radiating caloric in proportion to their temperature, and that those surfaces, which radiate least, make up for the deficiency, by reflecting most; so that the combination of reflection and radiation from any surface, when in æquilibrio with the surrounding bodies, is the same. When a body is heated, its radiation is increased, and therefore, when placed near a thermometer, it radiates more to the thermometer than it receives from it, and therefore elevates its temperature. When, on the other hand, a body is cooled, it intercepts from the thermometer near it part of the radiation of the surrounding objects, and it radiates less than it receives. The thermometer must therefore sink.
XIV. Method of determining the Latitude, by a Sextant or Circle, with simplicity and accuracy, from Circum-meridian Observations, taken near Noon
Authors: Brisbane Thomas
Published: January 2013

As it very frequently happens that an observation may not be obtained for the latitude, at the precise instant of noon, it becomes a most desirable object to supply that loss by every possible means. The method which I am about to detail, I have long practised, and from the experience of many hundred trials, I can recommend it, as combining much simplicity with the greatest accuracy; since one day's observations may be equal to those derived from the chances of three weeks of the ordinary course of weather in our climate. This method consists in merely reducing to noon these observations, the same as if made when the sun's centre was on the meridian, by the means of a very simple calculation, which I shall detail, and illustrate with the observations for two days, in order to shew the accuracy of the results thus obtained. Having previously ascertained the time of noon, either by equal altitudes, or from simple ones, in the manner I had the honour to detail in a former communication to the Society, “On the Mode of determining Time with the Sextant” I begin nearly 10′ from noon to observe the sun's altitude, from an artificial horizon of oil, or quicksilver, and continue making as many observations as I can accomplish until the sun has nearly the same altitude as when I began, which will be the case about as long past noon, during which an expert observer will easily take 20 altitudes, which, in most cases, will be sufficient to enable him to retain all those that appear to be consistent, and to reject those that differ much from the mean.
XVII. Description of a Magnetimeter, being a New Instrument for Measuring Magnetic Attractions, and Finding the Dip of the Needle; with an Account of Experiments made with it
Authors: Scoresby William
Published: January 2013

About ten months ago, I had the honour of communicating to the Royal Society, a description of a new instrument for ascertaining the Magnetic Dip. Having made very considerable improvements in the apparatus, by means of which some curious results on the magnetic laws, especially those that relate to the production and annihilation of magnetism in iron, have been obtained,—I now beg leave to submit to the Society a drawing and description of my improved instrument, together with an outline of some of the most interesting experiments made with it. Many of the results appear to me to be new; if so, their importance will be my excuse for repeating some parts of the description given in the former paper. It has been long known that iron might be rendered magnetical by percussion; but I am not aware that the precise effect of position has ever been suggested, I remain, &c.
Pretentiously detecting power cancellation
Authors: JUNG JUNEHYUK , OLIVER ROBERT J. LEMKE
Published: January 2013

Granville and Soundararajan have recently introduced the notion of pretentiousness in the study of multiplicative functions of modulus bounded by 1, essentially the idea that two functions which are similar in a precise sense should exhibit similar behavior. It turns out, somewhat surprisingly, that this does not directly extend to detecting power cancellation - there are multiplicative functions which exhibit as much cancellation as possible in their partial sums that, modified slightly, give rise to functions which exhibit almost as little as possible. We develop two new notions of pretentiousness under which power cancellation can be detected, one of which applies to a much broader class of multiplicative functions.
Systematically Bridging the Gap between Novae and Supernovae
Authors: Kasliwal Mansi M.
Published: January 2013

The venerable study of cosmic explosions is over a century old. However, until recently, there has existed a glaring six-magnitude luminosity gap between the brightest novae and faintest supernovae. To find optical transients that are fainter, faster, and rarer than supernovae, we designed a systematic search: the Palomar Transient Factory. Theorists predict a variety of mechanisms to produce transients in the gap and observers have the best chance of finding them in the local universe. Here I present discoveries and unique physics of cosmic explosions that bridge this gap between novae and supernovae.
“Pure” Supernovae and Dark Energy
Authors: Pruzhinskaya M. V. , Gorbovskoy E. S. , Lipunov V. M.
Published: January 2013

A special class of Type Ia supernovae that is not subject to ordinary and additional intragalactic gray absorption and chemical evolution has been identified. Analysis of the Hubble diagrams constructed for these supernovae confirms the accelerated expansion of the Universe irrespective of the chemical evolution and possible gray absorption in galaxies.
The SNLS-VLT Type Ia Spectrum Evolution with Redshift: a Demographic Effect?
Authors: Balland Christophe , Mouchet Martine
Published: January 2013

We build composite spectra at z ≤ 0.5 and z > 0.5 from the 3 year SuperNova Legacy Survey (SNLS) VLT spectral sample and study their differences around maximum light. We use 93 spectra near maximum of confirmed SNe Ia observed at the VLT between 2003 and 2006 as part of the 3 first years of operation of the SNLS. We find differences in the absorption depth of some intermediate mass elements (Ca ii, Si ii). Average stretches of observed distributions are 0.975 ± 0.016 and 0.983 ± 0.014 for the z ≤ 0.5 and z > 0.5 sample respectively. We use the A+B model of Scannapieco & Bildsten (2005) to interpret these results in terms of a possible demographic evolution.
White Dwarf Remnants of Binary Star Evolution
Authors: Tout Christopher A.
Published: January 2013

White dwarfs grow as the cores of red giants and, in particular, carbon-oxygen white dwarfs grow in asymptotic giant branch (AGB) stars. The evolution of an AGB star is a competition between growth of the core and loss of the stellar envelope, typically in a wind. It is complicated by thermal pulses driven periodically by unstable helium shell burning. Dredge up following such pulses delays core growth. The compression at the center of a cold carbon-oxygen core means that carbon ignites when it reaches a mass of 1.38 M⊙. This begins the familiar thermonuclear runaway of the Type Ia supernova (SN Ia). At higher temperatures carbon can ignite more gently and burn mostly to neon to leave a core rich in oxygen, neon and magnesium. Such cores can go on to collapse to neutron stars with a release of only neutrinos. Accepted mass-loss prescriptions for giants mean that the range of masses of single stars that leave carbon-oxygen white dwarfs is somewhere from around 1 to 8 M⊙. We investigate how unusual mass loss, perhaps brought about by interaction with a binary companion, can radically alter the single star picture. Though population syntheses treat some possibilities with various prescriptions, there is sufficient doubt over the physics, the observations, and the implementation of mass loss and binary interaction that there is scope for several more unusual progenitors of carbon-oxygen white dwarfs and hence SNe Ia.
White Dwarf Model Atmospheres: Synthetic Spectra for Supersoft Sources
Authors: Rauch Thomas
Published: January 2013

The Tübingen NLTE Model-Atmosphere Package (TMAP) calculates fully metal-line blanketed white dwarf model atmospheres and spectral energy distributions (SEDs) at a high level of sophistication. Such SEDs are easily accessible via the German Astrophysical Virtual Observatory (GAVO) service TheoSSA. We discuss applications of TMAP models to (pre) white dwarfs during the hottest stages of their stellar evolution, e.g. in the parameter range of novae and supersoft sources.
The Core-Degenerate Scenario for Type Ia Supernovae
Authors: Soker Noam
Published: January 2013

In the core-degenerate (CD) scenario for the formation of Type Ia supernovae (SNe Ia) the Chandrasekhar or super-Chandrasekhar mass white dwarf (WD) is formed at the termination of the common envelope phase or during the planetary nebula phase, from a merger of a WD companion with the hot core of a massive asymptotic giant branch (AGB) star. The WD is destroyed and accreted onto the more massive core. In the CD scenario the rapidly rotating WD is formed shortly after the stellar formation episode, and the delay from stellar formation to explosion is basically determined by the spin-down time of the rapidly rotating merger remnant. The spin-down is due to the magneto-dipole radiation torque. Several properties of the CD scenario make it attractive compared with the double-degenerate (DD) scenario. (1) Off-center ignition of carbon during the merger process is not likely to occur. (2) No large envelope is formed. Hence avoiding too much mass loss that might bring the merger remnant below the critical mass. (3) This model explains the finding that more luminous SNe Ia occur preferentially in star forming galaxies.
Episodic Mass Transfer: A Trigger for Nova Outbursts?
Authors: Williams Robert
Published: January 2013

High resolution spectra of post-outburst novae show multiple components of ejected gas that are kinematically distinct. We interpret the observations in terms of episodes of enhanced mass transfer originating from the secondary star that result in the formation of discrete components of circumbinary gas and accretion onto the white dwarf (WD) that trigger nova outbursts. In this picture the concordance between absorption line velocities and emission line widths in most novae occurs as a result of the collision of the expanding nova ejecta with a larger mass of surrounding circumbinary gas. One implication of this model is that much of the accreted gas remains on the WD, leading to a secular increase in WD mass over each outburst event. Alternative scenarios to explain nova spectral evolution are possible that do not invoke circumbinary gas and a possible test of different models is proposed.
Classical Novae as Supersoft X-ray Sources in the Andromeda Galaxy
Authors: Henze Martin , Pietsch Wolfgang , Haberl Frank , Hernanz Margarita , Sala Gloria , Valle Massimo Della , Hatzidimitriou Despina , Rau Arne , Hartmann Dieter H. , Burwitz Vadim , Greiner Jochen
Published: January 2013

We review the first results of a dedicated, on-going monitoring project for supersoft X-ray source (SSS) states of classical novae (CNe) in the central region of the Andromeda galaxy (M 31). So far, during three high-cadence observation campaigns with the X-ray telescopes XMM-Newton and Chandra from 2006 until 2009 we detected 21 CNe, only four of which were seen in X-rays before. This increased the total number of known CNe with X-ray counterparts in M 31 to 60, which is significantly larger than for any other galaxy, including the Milky Way. We compiled a catalog of X-ray and optical properties for these 60 sources which allowed us to perform source statistics and population studies of CNe with SSS state in M 31 for the first time. Here we review the results of this analysis: (i) several correlations between X-ray and optical parameters, (ii) an analysis of the intrinsic fraction of CNe with SSS state, and (iii) the first nova population study in X-rays. Our first results are promising, however a continuing monitoring of the unique target M 31 is strongly needed to extend this valuable data base and to refine the early statements and predictions.
V479 And: CV, LMXB, or Symbiotic?
Authors: Buitrago Diego González , Tovmassian Gagik , Echevarría Juan , Zharikov Sergey , Miyaji Takamitsu , Avilés Andres , Valyavin Gennady
Published: January 2013

V479 And is a 14.26 hour, close binary system, comprised of a G8-K0 star departing from the main sequence and a compact primary star accreting matter from the donor. The object is an X-ray source, modulated with the orbital period. This, and the presence of an intense He II line, leads us to speculate that the compact object is a magnetic white dwarf. However, we do not find strong constraints on the upper mass limit of the compact object, and we may have a neutron star in a low mass X-ray binary instead of a cataclysmic variable. The orbital period is certainly too short for the donor star to be an evolved giant star, so classifying this object as a symbiotic binary may be a big stretch; however there is an evidence that the mass transfer occurs via stellar winds, rather than through the L1 point of Roche filling secondary, a phenomenon more common for symbiotic stars.
Telescope and Researcher Potential of Turkey for Collaboration in CV Studies
Authors: Saygac A. Talat , Alis Sinan
Published: January 2013

The Turkish astronomical community has installed several telescopes during the last 10 years. We describe this work and discuss the potential of young researchers in Turkey, with the aim of fostering collaborations in the field of cataclysmic variables and related objects.
Photometric Investigation of the Dwarf Nova OT J213806.6+261957 in Pegasus
Authors: Zemko P. O. , Andreev M. V. , Chochol D. , Katysheva N. A. , Shugarov S. Y.
Published: January 2013

Our UBV(RI)C CCD photometry of a WZ Sge-type dwarf nova OT J213806.6+261957, discovered on May 6, 2010 at 8.4 mag, is presented. The analysis of our ~ 10000 CCD images, taken at observatories in Russia, Ukraine and Slovakia during May-November 2010, revealed the presence of ordinary and late superhumps. Fast brightness variations (flickering) on a time scale of minutes were also detected.
Ultra-soft Sources as Type Ia Supernovae Progenitors
Authors: Lepo Kelly , van Kerkwijk Marten
Published: January 2013

Missing from the usual considerations of nuclear burning white dwarfs as Type Ia supernovae progenitors are systems with very higher mass transfer rates, where more material than is needed for steady burning accretes on the white dwarf. This will expand the photosphere of the white dwarf, causing it to emit at longer wavelengths. Thus, we propose the name ultra-soft source (USS) for these objects.

We present a VLT/FLAMES survey looking for USSs in the SMC, selected to be bright in the far UV and with blue far UV-V colors. While we find some unusual objects, and recover known planetary nebulae and WR stars, we detect no objects with strong He II lines, which should be a signature of USSs. This null result either puts an upper limit on the number of USSs in the SMC, or shows that we do not understand what the optical spectra of such objects will look like.

We also discuss the unusual LMC [WN] planetary nebula LMC N66 as a possible example of a USS. It has a luminosity consistent with that expected, and its spectra show incompletely CNO-processed material — strong helium lines, some hydrogen, enhanced nitrogen and depleted carbon. It also shows periodic outbursts. USSs may resemble N66 in quiescence. However, it lacks a FUV excess, contrary to our predictions.
The Changing Nature of QU Carinae: SN Ia Progenitor or a Hoax?
Authors: Kafka Stella
Published: January 2013

The race to the elusive Type Ia supernovae (SNe Ia) progenitors is at its zenith, with numerous clues from SNe Ia ejecta and a dearth of observational candidates. Still, the single degenerate channel is a viable route of mass accumulation onto a white dwarf to the Chandrasekhar limit. I present long-term high resolution spectroscopy of QU Carinae, one of the most promising single degenerate SNe Ia progenitors. I discuss its highly variable nature and compare it to current scenarios for mass accumulation onto high-mass white dwarfs, eventually leading to WD detonation and to a supernova explosion.
White Dwarf Masses and Accretion Rates of Recurrent Novae: an X-ray Perspective
Authors: Mukai Koji , Sokoloski Jennifer L. , Nelson Thomas , Luna Gerardo J. M.
Published: January 2013

We present recent results of quiescent X-ray observations of recurrent novae (RNe) and related objects. Several RNe are luminous hard X-ray sources in quiescence, consistent with accretion onto a near Chandrasekhar mass white dwarf. Detection of similar hard X-ray emissions in old novae and other cataclysmic variables may lead to identification of additional RNe candidates. On the other hand, other RNe are found to be comparatively hard X-ray faint. We present several scenarios that may explain this dichotomy, which should be explored further.
The Mass of the White Dwarf in the Recurrent Nova CI Aquilae
Authors: Sahman D. I. , Dhillon V. S.
Published: January 2013

If recurrent novae (RNe) are progenitors of Type Ia Supernovae (SNe Ia), their white dwarfs (WD) must have masses close to the Chandrasekhar limit. The most reliable means of determining WD masses in RNe is dynamically, via radial-velocity and rotational-broadening measurements of the companion star. Such measurements require the system to be both eclipsing and to show absorption features from the secondary star. The only other reliable RNe mass estimate is for U Sco, which has a WD mass of 1.55 ± 0.24 M⊙ (Thoroughgood et al. 2001).

We present new time-resolved, intermediate-resolution spectroscopy of the eclipsing RN CI Aql during quiescence. We find the mass of the WD to be 1.02 ± 0.08 M⊙ and the mass of the secondary star to be 2.41 ± 0.2 M⊙. We estimate the radius of the secondary to be 2.10 ± 0.07 R⊙. The high mass ratio of q=2.37 ± 0.15 and the high secondary star mass suggests that mass transfer occurs on a thermal timescale. We suggest that CI Aql is evolving into a supersoft x-ray source, and ultimately will explode as an SN Ia.
New Photometric Observations of RS Oph
Authors: Voloshina Irina , Metlov Vladimir
Published: January 2013

The recurrent nova RS Oph is a long period (~455 days) binary system consisting of a hot white dwarf with mass close to the Chandrasekhar limit and an M-type giant secondary. Here we present the results of photometric observations of this nova which were made during recent years with the telescopes of the Sternberg Astronomical Institute in Crimea.
Helium Star Donor Channel to Type Ia Supernovae and Their Surviving Companion Stars
Authors: Wang Bo , Han Zhanwen
Published: January 2013

Employing Eggleton's stellar evolution code and assuming optically thick winds, we systematically studied the He star donor channel of Type Ia supernovae (SNe Ia), in which a carbon-oxygen white dwarf (WD) accretes material from a He main-sequence star or a He subgiant to increase its mass to the Chandrasekhar mass. We mapped out the initial parameters for producing SNe Ia in the orbital period–secondary mass plane for various WD masses from this channel. Based on a detailed binary population synthesis approach, we find that this channel can produce SNe Ia with short delay times (~100 Myr) implied by recent observations. We derived many properties of the surviving companions of this channel after SN explosion, which can be tested by future observations. We also find that the surviving companions from the SN explosion scenario have a high spatial velocity (>400 km/s), which could be an alternative origin for hypervelocity stars (HVSs), especially for HVSs such as US 708.