On the degree of uncertainty which local attraction, if not allowed for, occasions in the map of a country, and in the mean figure of the earth as determined by geodesy ; a method of obtaining the mean figure free from ambiguity by a comparison of the Anglo-Gallic, Russian, and Indian Arcs ; and speculations on the constitution of the earth's crust

1864 ◽  
Vol 13 ◽  
pp. 253-276 ◽  
Keyword(s):  
Royal Society ◽  
Earth’S Crust ◽  
Plumb Line ◽  
Remarkable Difference ◽  
Astronomical Society ◽  
Royal Astronomical Society ◽  
The Earth ◽  
Figure Of The Earth ◽  
The Mean ◽  
Earth's Crust

1. In former communications to the Royal Society I have shown that Local Attraction, owing to the amount it in some places attains, is a more troublesome element to deal with in geodetical operations than had generally been supposed. The Mountains and the Ocean were shown to combine to make the deviation of the plumb-line as much as 22".71, 17".23, 21".05, 34".16 (or quantities not differing materially from them) in the four principal stations of the Great Arc of India between Cape Comorin and the Himmalayas—viz. at Punnœ (8° 9' 31"), Damargida (18° 3' 15'), Kalianpur (24° 7' 11"), Kaliana (29° 30' 48") ; and how much these might be increased or lessened by the effect of variations of density in the crust below t was difficult to say. Deviations amounting to at least such quantities as 7''.61 and 7".87 were shown to exist in the stations of the Indian Arc, arising from this last cause (see Phil. Trans. 1861, p. 593 (4) and (5)). M. Otto Struve has lately called attention to similarly important deflections caused by local attraction in Russia—and especially to a remarkable difference of deflection at two stations near Moscow, only about eighteen miles apart, amounting to as much as 18", which is attributed to an invisible unknown cause in the strata below (see Monthly Notices of the Royal Astronomical Society, April 1862).

scholarly journals III. On the degree of uncertainty which local attraction, if not allowed for, occasions in the map of a country, and in the mean figure of the Earth as determined by geodesy: a method of obtaining the mean figure free from ambiguity, from a comparison of the Anglo-Gallic, Russian, and Indian arcs: and speculations on the constitution of the Earth’s crust

1864 ◽  
Vol 13 ◽  
pp. 18-19
Keyword(s):  
Earth’S Crust ◽  
Plumb Line ◽  
Level Surface ◽  
Middle Latitudes ◽  
The Earth ◽  
Figure Of The Earth ◽  
The Mean ◽  
Earth's Crust

After referring to a former paper in which he had shown that, in the Great Indian Arc of meridian, deflections of the plumb-line amounting to as much as 20" or 30" would be produced if there were no sources of compensation in variations of density beneath the surface of the earth, and after alluding to a remarkable local deflection which M. Otto Struve had discovered in the neighbourhood of Moscow, the author proceeds to consider, in the first instance, the effect of local attraction in mapping a country according to the method followed by geodesists, in which differences of latitude and longitude are determined by means of the measured lengths of arcs, by substituting these lengths and the observed middle latitudes in the known trigonometrical formulae, using the mean figure of the earth, although the actual level surface may differ from that belonging to the mean figure in consequence of local attraction.

scholarly journals XII. On the cause of the discrepancies observed by Mr. Baily with the Cavendish apparatus for determining the mean density of the earth

1847 ◽  
Vol 137 ◽  
pp. 217-229 ◽  
Keyword(s):  
Mathematical Theory ◽  
Full Account ◽  
Astronomical Society ◽  
Royal Astronomical Society ◽  
The Earth ◽  
Singular Source ◽  
The Mean ◽  
The Masses ◽  
Source Of Error ◽  
Different Parts

In the Fourteenth Volume of the Transactions of the Royal Astronomical Society will be found a full account of the Cavendish apparatus, and of the mode of experimenting followed by Mr. Baily. It will therefore not be necessary for me, in this place, to enter into any detail as to the different parts of the instrument, and the various precautions adopted in order to avoid that singular source of error 'currents of air in the torsion box arising from unequal temperature,’ which had been discovered by Cavendish. It will be sufficient for me to state that all the arrangements are of a highly satisfactory kind, and that I am of opinion that no aerial currents could have existed in the torsion box. The deduction of the mean density of the earth from the observed vibrations of the balls influenced by the torsion force and the attraction of the masses, is founded on a mathematical theory of the motion of the balls given by the Astronomer Royal, Mr. Airy ; and as this theory is certainly insufficient to account for the discrepancies, it will here be necessary to give a brief sketch of it.

scholarly journals III. On the theory of elliptic motion

1860 ◽  
Vol 10 ◽  
pp. 430-432
Keyword(s):  
Royal Society ◽  
Present Note ◽  
Radius Vector ◽  
True Anomaly ◽  
Periodic Part ◽  
Elliptic Motion ◽  
Astronomical Society ◽  
Royal Astronomical Society ◽  
The Mean

The present Note is intended to give an account of the results which, by means of a grant from the Donation Fund of the Royal Society, I have procured to be calculated for me by Messrs. Creedy and Davis, and which are contained in a memoir presented to the Royal Astronomical Society, entitled “Tables of the Developments of Functions in the Theory of Elliptic Motion." The notation employed is r , the radius vector; f , the true anomaly; a , the mean distance; e , the excentricity; g , the mean anomaly; so that r/a' = elqr(e, y) , and f, = elta ( e, g ) (read elliptic quotient radius and elliptic true anomaly), are known functions of e, g. Moreover x denotes the periodic part of r/a' and y the equation of the centre or periodic part of f ; so that r/a = 1 + x , f = g + y , and x, y are also known functions of e, g .

scholarly journals IV.—The Circular form of Mountain Chains

1903 ◽  
Vol 10 (7) ◽  
pp. 305-306
Author(s):  
Philip Lake
Keyword(s):  
Earth’S Crust ◽  
Mountain Ranges ◽  
The Earth ◽  
Circular Form ◽  
Thrust Plane ◽  
Figure Of The Earth ◽  
Mountain Chain ◽  
Earth's Crust ◽  
Reversed Fault

I am a stranger in the field of speculation, and am quite unacquainted with the intricacies of its authorized boundaries. It is therefore with some hesitation, lest I should tread upon forbidden ground, that I venture to offer a suggestion on one point in Professor Sollas's paper on “The Figure of the Earth.”It has long been observed that mountain ranges and chains of islands (which, indeed, are only mountain ranges partially submerged) are generally curvilinear in form, but Professor Sollas is, I believe, the first to show clearly that the curve often coincides almost exactly with an arc of a circle. Such a mountain chain is frequently defined along its convex margin by a great reversed fault over which the mountain mass has slid forward; and in these cases, at least, we may safely adopt Suess's conception, and look upon the chain as the crumpled edge of a ‘scale’ of the earth's crust which has been pushed forward over the part in front of it. The surface along which the movement has taken place is called a thrustplane. If this surface really is a plane, then the edge of the ‘scale’, that is the mountain chain itself, must necessarily be circular in form; for if any plane cuts a sphere, in any position whatever, the outcrop of the plane on the surface of the sphere will always be a circle. There can be no deviation from the circular form unless the ‘sphere’ is not truly spherical, or the ‘thrust-plane’ is not a true plane.

scholarly journals XIII. On the constitution of the solid crust of the Earth

1871 ◽  
Vol 161 ◽  
pp. 335-357 ◽  
Keyword(s):  
Sea Level ◽  
Plumb Line ◽  
Level Surface ◽  
Considerable Influence ◽  
The South ◽  
Vertical Column ◽  
The North ◽  
The Earth ◽  
Figure Of The Earth ◽  
The Mean

A few years ago I proposed the following hypothesis regarding the Constitution of the Earth’s Solid Crust, viz.: — that the variety we see in the elevation and depression of the earth’s surface, in mountains and plains and ocean-beds, has arisen from the mass having contracted unequally in becoming solid from a fluid or semifluid condition: and that below the sea-level under m ountains and plains there is a deficiency of m atter, approximately equal in amount to the mass above the sea-level; and th at below ocean-beds there is an excess of matter, approximately equal to the deficiency in the ocean when compared with rock; so that the amount of matter in any vertical column drawn from the surface to a level surface below the crust is now, and ever has been, approximately the same in every part of the earth. 2. The process by which I arrived at this hypothesis I will explain. In the Philosophical Transactions for 1855 and 1858 I showed that the Himalayas and the Ocean must have a considerable influence in producing deflection of the plumb-line in India. But by a calculation of the mean figure of the earth, taking into account the effect of local attraction, it appeared that no where on the Indian Arc of meridian through Cape Comorin is the resultant local attraction, arising from all causes, of great importance*. This result at once indicated that in the crust below there must be such variations of density as nearly to compensate for the large effects which would have resulted from the attraction of the mountains on the north of India and the vast ocean on the south, if they were the sole causes of disturbance, — and that, as this near compensation takes place all down the arc, nearly 1500 miles in length, the simplest hypothesis is, that beneath the mountains and plains there is a deficiency of matter nearly equal to the mass above the sea-level, and beneath ocean-beds an excess of matter nearly equal to the deficiency in the ocean itself.

2. On the Deflection of the Plumb-Line at Arthur's Seat, and on the Mean Density of the Earth.

1857 ◽  
Vol 3 ◽  
pp. 364-366 ◽  
Author(s):  
James
Keyword(s):  
Great Britain ◽  
Plumb Line ◽  
The Earth ◽  
Figure Of The Earth ◽  
The Mean

The author states that the results of the Trigonometrical Survey of Great Britain are nownearly ready for publication, and that he has deduced from them the most probable measures which they afford of the length of a meridian, and the figure of the earth.After determining the most probable spheroid from all the astronomical and geodetical operations in Great Britain, it has been found that the plumb-line is sensibly deflected at several of the trigonometrical stations; but in almost every case the physical cause of such irregularity may be with probability inferred.

III. An account of the great earthquake experienced in Chile on the 20th of February, 1835; with a map

1836 ◽  
Vol 126 ◽  
pp. 21-26 ◽  
Keyword(s):  
Royal Society ◽  
Earth’S Crust ◽  
Great Earthquake ◽  
Sea Birds ◽  
The Earth ◽  
Great Confidence ◽  
Earth's Crust ◽  
The Moment

The phenomena attending this great disturbance of the surface of the earth have been so varied, and the extent of its effects so considerable, that I should almost deviate from my duty if I did not endeavour to draw up and transmit to the Royal Society some account of a convulsion which has laid in ruins three provinces, and caused incalculable damage to the southern part of this country. I am the more inclined to take this step from a happy concurrence of circumstances having drawn several scientific observers to Concepcion shortly after the catastrophe, who have obligingly confided their notes to me. I trust therefore the Royal Society will not consider that I am about to trespass upon its time. An idea, in some degree fanciful, prevailed for some time after the conquest of these countries by the Spaniards, that these convulsions of the earth’s crust occurred at intervals of a century; afterwards it was supposed that about fifty years was the term which usually elapsed between great shocks; but, since the commencement of this century, the repeated catastrophes which have occurred, especially in the years 1812 in Caraccas, 1818 in Copiapo, 1822 in the province of Santiago, 1827 in Bogota, 1828 in Lima, 1829 in Santiago, and 1832 in Huasco, have prepared the minds of the inhabitants to expect at all times these frightful oscillations of the earth, which, although they cause little sensation at first, after some time affect the nerves in a manner not easy to account for by ordinary causes. That they happen at all times and in all states of the atmosphere seems clearly decided. The finest weather, and the most variable, equally prevail at the moment; but many are the fancied signs by which the coming earthquakes are predicted, and in the faith of which the inhabitants confide, as they think their experience bears them out. While some place great confidence in rats running violently over the ceilings of the room, others prepare for a shock when they observe the stars twinkling more than usual, and all fears are removed when much lightning coruscates in the Cordillera. As far as my own observations go, little reliance can be placed on the two former prognostics; something more certain seems to be due to the latter. A few hours previous to the earthquake which I am about to describe, immense flocks of sea birds proceeded from the coast towards the Cordillera, a circumstance which occurred prior to the great shock of 1822; and it is affirmed by too many respectable persons not to be entitled to some degree of credit, that on the morning of the convulsion all the dogs disappeared from Talcahuano.

scholarly journals INQUIRY INTO VERTICAL MOVEMENTS OF THE EARTH‘S CRUST BASED ON SAMPLES FROM EASTERN LITHUANIA

2014 ◽  
Vol 40 (2) ◽  
pp. 58-67
Author(s):  
Ruta Puziene ◽  
Asta Anikeniene ◽  
Gitana Karsokiene
Keyword(s):  
Regression Models ◽  
Earth’S Crust ◽  
Movement Velocity ◽  
Correlation Matrices ◽  
Vertical Movements ◽  
Statistical Correlations ◽  
Horizontal Gradients ◽  
The Earth ◽  
Earth's Crust ◽  
Made In

In the research of vertical movements of the earth’s crust, examination of statistical correlations between the measured vertical movements of the earth’s crust and territorial geo-indexes is accomplished with the help of mathematical statistical analysis. Availability of the precise repeated levelling measuring data coupled with the preferred research methodology offer a chance to determine and predict recent vertical movements of the earth’s crust. For the inquiry into recent vertical movements of the earth’s crust, a Lithuanian class I vertical network levelling polygon was used. Drawing on measurements made in the polygon, vertical velocities of earth’s crust movements were calculated along the following levelling lines. For determining the relations shared by vertical movements of the earth’s crust and territorial geo-parameters, the following territory-defining parameters are accepted. Examination of the special qualities of relations shared by vertical movements of the earth’s crust and geo-parameters in the territory under research contributed to the computation of correlation matrices. Regression models are worked out taking into consideration only particular territory-defining geo-parameters, i.e. only those parameters which exhibit the following correlation coefficient value of the vertical earth’s crust movement velocity: r ≥ 0.50. A forecast of the velocities pertaining to vertical movements of the earth’s crust in the territory under examination was made with the application of regression models. Further in the process of this research, a map was compiled specifying the velocities of vertical movements of the earth’s crust in the territory. In the eastern part of this territory, the earth’s crust rises at a rate of up to 3 mm/year; while in the western part of it, the earth crust lowers at a rate of up to –1.5 mm/year. In order to pinpoint territories characterised by temperate and regular rising/lowering or intensive rising/lowering, a map of horizontal gradients of recent vertical earth crust movements in the territory enclosed by levelling polygon was compiled.

scholarly journals Solar eclipse of May 28, 1900. Preliminary report of the expedition to the south limit of totality to obtain photographs of the flash spectrum in high solar latitudes

1901 ◽  
Vol 67 (435-441) ◽  
pp. 370-385 ◽  
Keyword(s):  
Solar Eclipse ◽  
Royal Society ◽  
Preliminary Report ◽  
The South ◽  
Astronomical Society ◽  
Royal Astronomical Society ◽  
The Government ◽  
Flash Spectrum ◽  
Government Grant

This expedition was one of those organised by the Joint Permanent Eclipse Committee of the Royal Society and the Royal Astronomical Society, funds being provided from a grant made by the Government Grant Committee. The following were the principal objects which I had in view in arranging the expedition:— To obtain a long series of photographs of the chromosphere and flash spectrum, including regions of the sun’s surface in mid-latitudes, and near one of the poles.

How I Learned to Stop Worrying and Love the TermAnthropocene

2014 ◽  
Vol 1 (2) ◽  
pp. 257-264 ◽  
Author(s):  
Timothy Morton
Keyword(s):  
Eighteenth Century ◽  
Royal Society ◽  
Earth’S Crust ◽  
Steam Engine ◽  
Radioactive Materials ◽  
Earth Systems ◽  
Huge Data ◽  
Earth's Crust ◽  
Great Acceleration ◽  
Geological Period

Not a day goes by in the 2010s without some humanities scholars becoming quite exercised about the termAnthropocene. In case we need reminding,Anthropocenenames the geological period starting in the later eighteenth century when, after the invention of the steam engine, humans began to deposit layers of carbon in Earth’s crust. Paul Crutzen and Eugene Stoermer’s term has been current since 2000.1In 1945, there occurred “The Great Acceleration,” a huge data spike in the graph of human involvement in Earth systems. (The title’s Kubrick joke stems from the crustal deposition of radioactive materials since 1945.) Like Marx, Crutzen sees the steam engine as iconic. As this is written, geologists such as Jan Zalasiewicz are convincing the Royal Society of Geologists to make the term official.

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